UMTS and Mobile Computing
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UMTS and Mobile Computing
For a listing of recent titles in the Artech House Mobile Communications Series, turn to the back of this book.
UMTS and Mobile Computing Alexander Joseph Huber Josef Franz Huber
Artech House Boston London www.artechhouse.com
Library of Congress Cataloging-in-Publication Data Huber, Alexander Joseph. UMTS and mobile computing / Alexander Joseph Huber, Josef Franz Huber. p. cm. (Artech House mobile communications library) Includes bibliographical references and index. ISBN 1-58053-264-0 (alk. paper) 1. Mobile communication systems. 2. Wireless communication systems. 3. Global system for mobile communications. I. Huber, Josef Franz. II. Title. III. Series. TK6570.M6 H83 2002 004.6dc21 2002019676 British Library Cataloguing in Publication Data Huber, Alexander Joseph UMTS and mobile computing. (Artech House mobile communications series) 1. Mobile computing 2. Mobile communication systems I. Title II. Huber, Josef Franz 004.6 ISBN 1-58053-264-0 Cover design by Igor Valdman UMTS is a trade mark of ETSI (European Telecommunications Standards Institute) registered in Europe and for the benefit of ETSI members and any user of ETSI Standards. We have been duly authorized by ETSI to use the word UMTS, and reference to that word throughout this book should be understood as UMTS.
© 2002 ARTECH HOUSE, INC. 685 Canton Street Norwood, MA 02062 All rights reserved. Printed and bound in the United States of America. No part of this book may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage and retrieval system, without permission in writing from the publisher. All terms mentioned in this book that are known to be trademarks or service marks have been appropriately capitalized. Artech House cannot attest to the accuracy of this information. Use of a term in this book should not be regarded as affecting the validity of any trademark or service mark. International Standard Book Number: 1-58053-264-0 Library of Congress Catalog Card Number: 2002019676 10 9 8 7 6 5 4 3 2 1
Contents Foreword 1
xi
Foreword 2
xiii
Preface
xv
Introduction
1
1.1
Mobile Computing and Ubiquitous Computing
2
1.2
The Driving Factor of Mobility
5
1.3 1.3.1 1.3.2
Innovation Drivers Moores Law Compression Standards for Multimedia: JPEG, MP3, MPEG-4, MPEG-7 Wireless Technologies Migrate to Configurable Radio and Smart Antennas The Internet, Intranets, and Mobility Services and Applications
9 9
12 15 16
References
16
2
The Market for UC
17
2.1
Mobile Market Developments
17
1.3.3 1.3.4 1.3.5
v
11
vi
UMTS and Mobile Computing
2.1.1 2.1.2 2.2 2.2.1 2.2.2 2.2.3 2.2.4 2.2.5 2.2.6 2.3 2.3.1
Emerging Wireless Personal Area and Wireless Local Area Networks Mobile Satellite Network Markets Internet Market Developments Challenge: Transition from Circuit Switching to Packet Switching Internet Access from Mobile Devices The Web Market Electronic Commerce: A Fundamental Component of Future Multimedia Services Intranet Need for Mobile Extensions Intranet Access from Mobile Devices
20 22 22 25 27 28 29 29 30
Fixed and Mobile Convergence Mobile Computer-Based Communications and UMTS Increasing Mobility of Individuals and the Pressure to Turn Dead Time into Productive Time Key Enablers Broadband Wireless Convergence Broadcasting Convergence Convergence on Devices Convergence and the Creation of New Services
32 33 34 35 35 36
References
36
3
Technologies
37
3.1 3.1.1 3.1.2 3.1.3 3.1.4 3.1.5 3.1.6
Mobile Wireless Communication Technologies WPANs WLANs Wireless WANs Extended Area Networks Other Technologies Technology Positioning and Comparison
37 43 56 63 86 96 98
3.2
UMTS
2.3.2 2.3.3 2.3.4 2.3.5 2.3.6 2.3.7
30 31
100
Contents 3.2.1
vii
3.2.2 3.2.3 3.2.4 3.2.5 3.2.6 3.2.7 3.2.8
Value ChainDevelopments Towards Information-Based Services Network Architecture UMTS Radio Access Techniques Core Network Internet Service Providers Function Mobile Portals Function UMTS Terminal Technologies USIM Cards and Smart Cards
103 105 110 120 129 132 141 144
3.3 3.3.1 3.3.2 3.3.3 3.3.4 3.3.5
UC Appliances (Devices) Card Technologies The iButton Tag Technologies Mobile 3G Devices Devices Summary
145 147 160 168 192 230
References
234
4
Standardization
241
4.1 4.1.1 4.1.2 4.1.3
WPAN and WLAN Standardization Bluetooth IEEE 802.X Standards DECT and PHS
243 243 245 249
4.2 4.2.1 4.2.2 4.2.3
3G Standardization 3GPP Develops Specifications for Global Use Internet-Related Standardization Standard Protocol Layers in UMTS
250 250 252 256
4.3
Addressing and Registration Standards
258
4.4 4.4.1 4.4.2 4.4.3
Standards for Information Encoding Voice Encoding Bitmap, Graphic, and Photographic-Image Encoding Video and Audio Compression
263 265 265 266
4.5
Software, Protocols, Computer Languages, and Smart Cards
274
viii
UMTS and Mobile Computing
4.5.1 4.5.2 4.5.3
SOAP CORBA Java Programming and Java Remote Method Invocation Jini HAVi UPnP OSGI Home Plug and Play Web Programming and Markup Language Standards WAP Smart-Card Standardization
279 280 280 282 282 283 284 289 291
References
296
5
Applications
299
5.1 5.1.1 5.1.2 5.1.3 5.1.4 5.1.5 5.1.6
UMTS Services and Applications Mobile Internet and Intranet Access Customized Infotainment and Edutainment Multimedia Messaging Services Location-Based Services Voice- and Videotelephony and -conferencing UMTS Services Portability
304 304 306 307 310 315 316
5.2
Examples: WAP and i-Mode
318
5.3 5.3.1 5.3.2 5.3.3
Telemetry Vehicle-Related Mobile Computing Health Care Other Applications
322 324 326 329
5.4
Mobile E-Commerce
329
References
333
6
Resource Issues
335
6.1 6.1.1
Addressing Capacity in Networked Environments Address Schemes
335 336
4.5.4 4.5.5 4.5.6 4.5.7 4.5.8 4.5.9 4.5.10 4.5.11
276 276
Contents
ix
6.1.2
Estimations of Address Capacity
339
6.2 6.2.1
Frequency Spectrum How Much Frequency Spectrum Is Needed for 3G Services? 3G Traffic Capacity Calculations Worldwide 3G Spectrum Identification What Is the UMTS-Specific Spectrum Demand per Operator in the Initial Phase? Spectrum Demand for WLANs or Ad Hoc Networks Worldwide WLAN Spectrum Identification
344
6.2.2 6.2.3 6.2.4 6.2.5 6.2.6
346 347 353 359 359 361
References
363
7
Outlook: Telecom + Datacom + Media = Infocom
365
7.1
Taking Moores Law into the Future
369
7.2
Future Network Architectures
371
7.3
Devices
375
7.4
The Smart-Card Issue
377
7.5
New Services and Applications
378
7.6
Mobile Agents
379
7.7
Industry Outlook
380
7.8
Researchers Move to 4G Mobile Radio Systems
381
7.9
Market Development
383
References
384
List of Acronyms
387
About the Authors
415
Index
419
Foreword 1 Any sufficiently advanced technology is indistinguishable from magic. Arthur C. Clarke, The Lost World of 2001
The dawn of the twenty-first century sees us standing on the threshold of the introduction of the Third Generation Universal Mobile Telecommunications System (UMTS). UMTS is not just an access technology or a technical platform, it is much more: a communication system leading the mobile user of the twenty-first century into a new mobile multimedia world linked with the Internet world. In 2001 NTT DoCoMo in Japan became the first company to offer mobile users Internet access including video calls at comfortable speeds via mobile devices, as well as voice and messaging services. Consumers are now able to enjoy the whole beauty of telecommunications in speed and capacity anywhere and anytime. Alexander and Josef Huber are offering readers very interesting insight into the converging world of mobile broadband multimedia and mobile computing to understand, on one hand, the underlying technology and, on the other hand, the driving forces of service, applications, portals, and more. I very much welcome the publication of this book as a tailored guidance into the complicated issue of modern converging communications. Dr. Bernd Eylert Chairman UMTS Forum March 2002 xi
Foreword 2 Readers of this book will note from its table of contents that it offers a comprehensive review and analysis of the confluence of mobility and computing. As the authors suggest, the ubiquitous computing concept (pioneered by the late Mark Weiser of Xerox PARC) has a natural implication that billions of smart, programmable devices will also be portable and a good many of them will be useful for and used in mobile operation. It is worth distinguishing between portability and mobility. Portable, networked devices may be moved from place to place and usedin place. Mobile, networked devices are intended to be used while in transit. Plainly, a mobile device may serve as a portable device, but a portable device may not be equipped to be used in motion. The requirements that must be satisfied may not be terribly dissimilar. For example, a portable, Internet-enabled device will need an IP address while it is in use, but it might be assigned such an address each time it is pressed into service, and this address need not necessarily be fixed or the same each time the device is used. Techniques like dynamic host configuration are designed to serve this requirement. However, if the device must be found by others, as opposed to always initiating contact, then additional methods must be sought. The concept of mobile IP has been explored in considerable detail by the Internet Engineering Task Force and generally involves the use of a home proxy that retains a permanent IP address and is responsible for keeping track of the current actual IP address associated with the mobile device. Other ideas have been put forward, such as dynamic domain name services in which the IP address associated with a domain name is dynamically changed. xiii
xiv
UMTS and Mobile Computing
In the world of IPv6, which is beginning to emerge from its experimental condition into native mode operation, ideas, such as a 64-bit unique device identifier and a separate 64-bit routing identifier, are combined into a 128bit IPv6 address. The Instant Messaging service of AOL among other peer-to-peer applications has created a widespread appreciation for the concept of presence. In this case, interested parties look to on-line databases to discover the whereabouts (i.e., IP address) of a party associated with a particular identifier. These applications allow users to select their own identifiers and the client side of the application updates the database as the client discovers its most recently assigned IP address. Looking up an identifier in such a database allows a form of rendezvous, permitting one party to signal the other, either through a rendezvous server (as with AOLs Instant Messaging) or directly, in the event that the actual IP address is revealed to the party wishing to rendezvous. There are myriad technical and policy issues arising from the consideration of mobility, not the least of which concerns the privacy of the mobile party whose whereabouts may be revealed as a consequence of the operation of presence and rendezvous mechanisms. Moreover, the stage is being set for the interaction of billions upon billions of programmable devices. One cannot help but wonder what emergent properties will be revealed as this amount of software, together with all its various bugs, is made to interwork over the Internet and other networks. Particularly striking about this book is its wide-ranging scope and the innovative perspective the authors bring to the subject. There is little doubt in my mind that the mobile environment will not merely enable us to blaze new trails in networking, but will force us to do so, thanks to the many challenges these capabilities will place before us. One suspects that the policy challenges may well be much more difficult to surmount than the technical ones, which will be interesting enough in their own right. Vinton G. Cerf Camelot March 2002
Preface Over the last 10 years, dramatic advances in computing power and software have enabled significant developments in computing, networking, and mobility. Personal computers, CD-ROM and DVD technology, digital television, mobile and satellite telecommunication networks, fiber-optic transmission, and the Internet and intranets have had considerable impact on the development of our society. Developing countries, in particular, have benefited from mobile communications technologies, which have made possible a very fast growth in their telecommunications infrastructures. By the end of 2001, the mobile networks market, for example, has reached approximately 950 million users, and the Internet has more than 400 million. The enormous progress in information and telecommunication technologies over the past decade has led to the creation of an information societya term that describes a society characterized by knowledge-based workers, new flexible work practices in education, industry, and private life, intelligent equipment, and mobility and networking in multimedia. In this information society, information is an important production factor in an increasingly global competitive market. Business processes are based more and more on efficient information and communication technologies. The world economy and society is changing. Large and small businesses alike are being organized differently; they are becoming more and more global rather than regional or local. Information plays an increasingly important role. Many organizations are looking to identify and capitalize on the promise of new market opportunities in multimedia created by these technological developments. Greater pressure on time and the need for xv
xvi
UMTS and Mobile Computing
mobility and personalization lead to a growing demand for mobile access to servicesanytime, anywhere. Multimedia is a catchword that is used in various ways, either as an indication of the dawning of a great time when we reach the promised land of milk and honey, or on the contrary, where it seems to be the ultimate stage of communications. If not already here, the time is near when terminals will enable virtual work teams, even when on the move, to focus on common tasks. People on the street will be able to access information instantly on local films fitting their tasteand download video clips of potential shows if requested. Tourists will download directly to their handhelds the map and historical information of a desired sight. Commuters will be able to play a round of bridge with friends while traveling to work. Alternatively, the commuter could enjoy a personalized newspaper. There will be machine-to-machine communications (e.g., in vehicles and households). Visionaries like Mark Weiser, who worked for the Computer Science Laboratory at XEROX Parc USA, had by 1988 already started to talk about a new paradigm in computing, where computers would be everywhere, and become more and more integrated into natural environments. He imagined computers so embedded, so naturally integrated, that we would use them without even thinking about it. He called this vision ubiquitous computing. Driven by the success of the World Wide Web in the 1990s, enthusiasm for the New Economy was reinforced by the emerging discussion of the Universal Mobile Telecommunication System (UMTS) on a global scope, which represented the principal of third-generation (3G) mobile network technology. In 2001, however, critical voices and press views introduced doubt to the promise of these new technologies. These doubts remind us of similar critics in historycritics of revolutionary inventions, such as book printing, the steam engine, railways, and automobileswho caused vigorous debates about their value for and future impact on society. The big question always is, how will paradigm changes be handled, and how fast will changes take place? Paradigm changes are always difficult; societys acceptance threshold is sometimes like a wall that hinders the breakthrough of new ideas and concepts. Knowledge and visibility can lower this threshold. This book contributes to the debate by describing the status of ubiquitous computing from a wireless networking perspective and focusing on 3G mobile technology. Third-generation mobile technology takes us from pure talking and listening to seeing, from voice to videojust like we went from radio sound to television pictures in the past. Already, both the technologies and the market demand exist. From a technological point of view, we see two
Preface
xvii
waves of innovation coming together in a timely, synchronous manner, thus encouraging new developments on both sides because of their synergies. On the computing side we see the simultaneous miniaturization and growth of computing power: the wave of mobile computing. On the networking side, we see mobile networks and the Internet coming together: the wave of mobile multimedia communication. This is the beginning of something new. We also see that a new understanding of advanced communications is taking place, which drifts away from the stupid network paradigm. The network is no longer just bit transport and switching; it now collects, aggregates, and prepares information on the applications level related to end users and devices. In the next stage of development, the actual situation of a person or device will be taken into account and the age of situation-dependent computing and communications will begin. This is what we understand to be the coming ubiquitous computing era. We thank our supporters, who helped us prepare this book. Our special thanks go to Michaela and Heidi for their editorial assistance and to Erika and Oliver for their appreciation.
1 Introduction It is a fact: The economy is going global. No wonder that global networking plays an increasing role and that information is an increasingly important factor in daily business. In 2001, the Internet enabled more than 400 million users worldwide to access several billion Web pages, and in the emerging area of e-commerce, huge amounts of money were spent on goods and services. Another fact is that the cost of information technology is falling much faster than for any previous technology. Over the past few decades, the real price for computer processing power has dropped by 99%, an average decline of 35% per year. The size and weight of computers have become considerably smaller, and mobile computers have reached the performance previously only seen with desktops. It is obvious that the stupid network paradigm will not continue; instead, network intelligence will be the keyword of the future. Network intelligence means functionalitywhich is flexible regarding fixed and mobile access, which has the knowledge of where the user is, which is able to aggregate content related to personal profiles, and which manages mobility. Of course, the available Internet protocols (IPs) will play a distinctive role and will challenge the telecommunication companies and the computer industry in many areas. What about the markets? The growing wireless and Internet and intranet markets will challenge the computer industry in many fields. While the wireless markets require small and lightweight portable devices with intelligence tailored to users needs, the Internet and intranet markets require 1
2
UMTS and Mobile Computing
higher transmission bit rates, more processing power, and increased memory capacity. As computing becomes increasingly mobile, communication systems are becoming increasingly interdependent. As this trend continues, the computing community will be forced not only to develop revolutionary systems, but also to redefine computing, including its hierarchical system architectures and operating systems (OSs), its traditional computer languages, and its networking structures. The focus on development efforts towards miniaturization, networking, personalization, portability, and mobility emphasizes this trend. Moores Law may continue to provide duplication of processing power every 18 months, and new computer-controlled stationary and portable devices with higher performance and low power consumption will enrich the computer world. These devices will pave the way to mobile computing.
1.1 Mobile Computing and Ubiquitous Computing Discussion about ubiquitous computing (UC, or ubicomp) has been going on for many years. UC describes the evolution of computing towards the socalled third era of computing. Mobile computing will be a main contributor to this development. The main aim of UC is to embed many small and highly specialized devices within the everyday environment in such a way that they operate seamlessly and become transparent to the person using them. They will operate either off-line or on-line. UC products aim to be everywhere (e.g., by being portable), to be small, and to be aware (of their environments, users, the contexts). Products and devices embodying these characteristics will provide a physical entity with complete freedom of movement as well as freedom of interaction. In his famous 1991 article, The Computer for the 21st Century [1], Mark Weiser introduced his vision of UC. The cornerstones of this vision are that computers as they are known today will be replaced by a multitude of networked computing devices embedded in our environments and that these devices will be invisible in the sense of not being perceived as computers. UC has two main features: • Ubiquity: Interactions are channeled through multiple interfaces
rather than a single workstation.
• Transparency: The technology becomes so embedded in everyday life
that it essentially becomes invisible to users.
Introduction
3
Mark Weiser called UC the third wave in computing, just now beginning: First were mainframes, each shared by lots of people. Now we are in the client-server personal computing era, with the person as the client being dependent on a machine, the server. Next comes personal mobile computing, still client-server-based. Finally, UC is seen as the age of calm technology, when technology recedes into the background of our lives [2]. The defining words will not be intelligent or agent, but rather invisible, calm, and connection. Many computers will serve each person everywhere in the world. The UC eras crossover point with desktop computing is thought to be around 2005 to 2010. The UC era will be defined by many computers shared by each of us. We may access some of these computers in the course of a few minutes of Internet browsing. Others will be embedded in walls, chairs, clothing, light switches, carsin everything. UC is fundamentally characterized by the connection of things in the world with computation. This will take place at many levels, including the microscopic. Mark Weiser envisioned the future as one where embedded computers would bring other worlds to us in new wayssometimes in ways so unobtrusive that we will not even notice our increased ability for informed action. As an example of how this might work, Weiser describes the kind of music your wake-up device will play: The kind of tune [it] plays to wake me up will tell me something about my first few appointments of the day. A quick urgent tune: 8 a.m. important meeting. Quiet, reflective music: Nothing until noon. In this way, the computer can be suggestive without being intermediating. Computers will act like books, windows, walks around the block, phone calls to relatives. They wont replace these, but augment them, make them easier, more fun. Dwelling with computers, they become part of the informing environment, like weather, like street sounds [1, 2]. Thus, mobile com- puting could help to free our minds from unnecessary work so that we can focus on the things and issues that are really important, interesting, and challenging. There is much talk today about thin clients, meaning lightweight Internet access devices costing only a few hundred dollars. UC will see the creation of thin servers, which will cost only tens of dollars or less and will put a full Internet server into every household appliance and piece of office equipment. The social impact of embedded computers may be analogous to two other technologies that have become ubiquitous: writing, which is found everywhere from clothes labels to billboards, and electricity, which surges invisibly through the walls of every home, office, and car. Writing and electricity have become so commonplace, so unremarkable, that we forget their huge impact on everyday life. So it will be with UC.
4
UMTS and Mobile Computing
Two predecessors of the coming UC era are found in fields of embedded microprocessors and the Internet. It is easy to find 40 microprocessors in an average home in the United States today: in alarm clocks, in microwave ovens, in TV remote controls, in stereos and TV sets, and in childrens toys. These microprocessors do not yet qualify as UC for two reasons: they are mostly used one at a time, and they are still masquerading as old-style devices like toasters and clocks. But if they were networked together, they would become an enabling technology for UC. If they were tied to the Internet, they would be connected with millions of information sources: clocks that find out the correct time after a power failure, microwave ovens that download new recipes, childrens toys that are ever refreshed with new software and vocabularies, paint that cleans off dust and notifies you of intruders, and walls that selectively dampen sounds are just a few possibilities [3]. These examples belong to mobile computing, an enabler for UC. Let us consider such development in three phases. The first phase is one where there are millions of computing devices, many of which are working off-line. They range in size from smaller than that of a memo pad to larger than that of desktops and computer towers. In this phase there are also the mobile terminals of first- and second-generation (1G and 2G) wireless networks, which provide voice and simple data. Their interconnection capabilities are still limited with regards to bit rate and reachability. The second phase adds multimedia mobility. Many computing devices in this phase will have more enhanced mobile data communications capability (e.g., multiservice networking). Universal use and portability of devices and services will play an important role. It will be possible to present a virtual home environment (VHE) to the user. Third-generation (3G) mobile networks will provide both multimedia communication with medium to high bit rates and the necessary networking support for client-server-based computing required for the mobile Internet. The term multimedia communication means the interaction of a human being with either one or a group of other human beings or a machine or computer, anywhere on the globe, exchanging or retrieving information by means of a dialog. In a multimedia communication, more complete information can be transferred by combining visual, audio, and manual elements, such as still or moving pictures, graphics, movies, sound, music, data, or any combination of these. Personalization is the key concept in the third phase. In this phase, mobile computing will not only be related to persons; the pet, the car, the office, and the home that are related to a person will have a communication relation with the person. Personalization in the multimedia sector already has its beginnings in phase one and two, when roaming takes place and the
Introduction
5
roaming person or device is identified with a personal address. In phase three, however, the position of an individual, say a person or a device, and the users need will additionally determine the selection of locationand person-related parameters and situation-dependent content. Learning and adaptive networked environments will address user needs, and personalization will become part of nearly all devices in the future. The immediate ad hoc environment will play an important role in this wireless and mobile world. This will lead to personal area or ad hoc networks being embedded into 3G wide area mobile networks. Peer-to-peer communication will come into play and provide autonomous many-to-many communications. Examples are cars interacting with other cars as a first step, and persons with interaction support as an additional step. The third phase will be the era of situation-dependent computing. These development phases will only happen if sufficient radio coverage in wide area and personal areas is available to provide acceptable bit rates and sufficient traffic capacity. Mobile computing and small appliances are already found in many environments operating off-line. Currently, there are product developments and prototypes that support Mark Weisers theory and that might prove him right: lightweight Internet access devices are available from different manufacturers like Palm, Handspring, Compaq, and Apple, to name a few. In addition, many mobile handhelds are made Internet capable. Internetenabled household appliances and office equipment are also already available, like the interconnected smart refrigerator [4] or the Internet-enabled washing machine [5]. Thin servers and embedded computing devices are available, like Texas Instruments TINI [6], the Matchbox Server from Professor Vaughan Pratt of Stanford University [7], and Cell Computings Card PC [8]. The new Internet Protocol version 6 (IPv6), which is coming into use, allows a unique address for any computing device. In order to realize full and complete UC scenarios, however, additional work and research is necessary in many different areas of computing, including ad hoc wireless communication networks, converged radio network solutions, network organization, service and object discovery, portable multimedia user devices, positioning, and adaptive ergonomic user interfaces.
1.2 The Driving Factor of Mobility In order to understand the forthcoming developments towards the third wave in computing, it is important to analyze market trends in a broader
6
UMTS and Mobile Computing
context. The old vision of the Internet was built around desktop PCs. The new vision adds a myriad of smaller portable devices like notepads, laptop PCs, personal digital assistants (PDAs), mobile handhelds, and hometelevision set-top boxes. None of these will replace the PC. Rather, they will broaden the total marketplace for delivery and processing of information. The Internet will change from a wireline-based medium for e-mail, advertising, marketing, and customer support to a common platform for transactions and business applications. At the same time, mobile IP-based networks and wireless technologies are emerging that will change the behavior of consumers. Mobility is a new and increasingly widespread feature of our daily life. It brings new features into the Internet and opens the door for a variety of new services and applications. Figure 1.1 shows the growth of these markets in contrast to the fixed telecommunications services. In addition, the expected growth of mobile Internet users is shown as a share of the total mobile market. Mobile data communication has been for a long time the province of companies using dedicated technologies for specific purposes. A number of developments in recent years, however, mean that the picture is changing: • Cellular networks. The scale on which Global System for Mobile
Communications (GSM) is being globally adopted, combined with the technologies of wideband code division multiple access (WCDMA) and IP transport, leads to a fundamental change in the mobile environment: Increased functionality provides a platform for Mobile networks (total)
Subscriptions worldwide (millions)
2,000 1,800 1,600
Fixed networks (total) Mobile Internet (share of mobile networks)
1,400 1,200 1,000
Fixed Internet (total)
800 600 400 200 0
1995
2000
2005
2010
Figure 1.1 Global market forecast for the Internet, fixed telecommunications, and mobile networks. (Source: Siemens AG.)
Introduction
7
the development of widespread services and applications, particularly as enhancements to basic systems start to provide higher speed data services. • Internet. Today the Internet is widely known and used for work and
leisure alike. Its growth has been phenomenal and its importance lies as much in changing attitudes about the use of communications technology as in any single piece of functionality it provides. Its power lies in its flexibility, which allows the same basic infrastructure to power a range of applications, from basic messaging to multimedia conferencing.
• Intranet. The corporate world has been quick to see the potential
benefits of the Internet and to adopt Internet technologies as a way of enabling access to corporate information and the construction of virtual communities within organizations.
• Terminals. Laptops, notebooks, smart phones, and PDAs are cur-
rently the most important mobile computing terminals, but this is changing as smaller product forms begin to meet the functionality requirements of mobile users, in terms of interface, weight, size, and battery power. For an increasingly mobile workforce, smart phones and handheld devices will play a large role in facilitating work. Peripherals, such as Personal Computer Memory Card International Association (PCMCIA) cards provide a standard interface for mobile devices, and commonality in software is increasingly the norm.
• Changing work patterns. Increasingly, sections of the workforce are
working flexibly from home or on the move. Much of the demand for mobile connectivity comes from professional and managerial groups who need to remain connected to their core information and contacts while away from base. Mobile Internet and intranet will form a core component of this connectivity.
Wireless Internet and Mobile InternetIs There a Difference?
The likely impact of wireless developments on the marketplace has been underestimated. The breakthrough occurred with the introduction of digital mobile cellular systems (2G) in the early 1990sjust like the Internet after the introduction of the World Wide Web (WWW, or the Web). Initially built on the basis of the traditional telecommunications network standards, these systems are bringing mobility and person-related services to the end
8
UMTS and Mobile Computing
user. With the evolution from 2G to 3G mobile networks, wideband radio access and Internet-based protocols will dominate and prepare the way from a mobile handset today to a mobile multimedia device in the future. Providing wireless access to the wireline Internet brings, of course, more flexibility and facilitates penetration. It is not, however, generating new services. New services come with new enabling functionslike mobility, personalization, and localization capabilitieswhich are the characteristics of 3G mobile systems. This is the motivation for the industry to evolve the wireline Internet to a mobile Internet with new capabilities and applications. Key enabling functions for the mobile Internet are as follows: • IP-transparency. All elements involved in the end-to-end communi-
cations path have to support IP, both in the fixed and in the mobile parts of the network.
• Mobility management. It has to function in a globally networked
environment for roaming.
• Addressing. It must allow every user a unique address capability,
which is independent from the users location.
• Personalization of information and positioning. There must be means
to provide such functionality.
• Positioning. The individual must be positioned to enable location-
dependent services.
• Security. It has to be provided end-to-end for fixed and mobile users.
Such preconditions will make the mobile Internet different from a wireless Internet that is understood as the Internet with the provisioning of wireless access in addition to wireline access. Mobile Internet brings more value and integrates mobile and fixed users; this is understood as convergence. The combination of Internet technology with mobile connectivity holds out the prospect of the marriage of two of the biggest and fastest growing markets in telecommunications. The mobile Internet will be a generator of new services, which will emerge from new features of a universal network that will reach the user anywhere in the world and that will support users by knowing their location and current environment. It will enhance e-commerce by enabling a mobile device to do such things as mobile shopping and mobile identification. Developing packages of services, terminals, and applications for users will be one of the key challenges to the mobile supply community over the coming decade. Another challenge will be the new
Introduction
9
business value chain, which provides many new business opportunities for market players.
1.3 Innovation Drivers 1.3.1
Moores Law
The phenomenon known as Moores Law1 the processor doubles its performance every 18 months to 2 years, while cost and power consumption fall almost as dramaticallydoes not appear to be approaching its limits (see Figure 1.2). Limits may be set, however, by the ability of the industry to generate the exponential capital investments needed to create fabrication facilities for each technology step. Such limitations will have profound implications for the extent to which chip technologies will influence radio technologies in the future. Within the next few years, the implementation of software radio will determine the cost and flexibility of mobile terminals. The steady down-scaling of complimentary metalloxide silicon (CMOS)technology dimensions has been the main stimulus to the growth 10
10 9
10 Components per chip
8
10
7
10
6
10
5
10
4
4 Gbit 1 Gbit 256 Mbit 64 Mbit 16 Mbit 4 Mbit 1 Mbit Alpha 256 Kbit Pentium Intel 486 Intel 386
DRAM Processors
Gate arrays Pentium 4 Micro 2000
Intel 80286
10
3
10
1980
1990 2000 Market launch year
2010
Figure 1.2 Chip technologies.
1. Gordon Moore, cofounder of INTEL, said in 1965, The pace of microchip technology change is such that the amount of data storage doubles every year or at least every 18 months.
10
UMTS and Mobile Computing
of microelectronics and computers over the past two decades. The more an integrated circuit is packed, the higher its circuit speed and the lower its power dissipation. Advances in lithography will enable CMOS-technology to be built for many more years. There are views that Moores Law will continue to hold over the next 10 to 15 years (the Intel Study Micro 2011 predicts one billion transistors per chip in 2011). If this is true, then by about 2015, designers will have to work on the molecular level. This molecular nanotechnology will fundamentally alter the way of manufacturing. A good example of such development is Intels Pentium processor. At the start of the Pentium series, processor power was measured by a clock rate of 150 MHz and the number of transistors was 140 million. By 2000, both the clock frequency and the number of transistors had increased by a factor of six; these improvements were reflected in increased functionality and performance. By 2001, the AMD Athlon processor reached a clock rate in excess of 1.3 GHz and was composed of more than 1 billion transistors. By mid-2001, the 2-GHz Intel Pentium 4 arrived on the marketplace, providing even better performance than the Athlon, especially for video applications. These numbers demonstrate that we have approached a technological level that will revolutionize the organization and architecture in machines and systems. This may lead to dynamic optimization and adaptation. The high levels of processing, memory, and communications power predicted for handheld and wearable computers (mobile multimedia terminals and mobile TV sets) in the next 10 years, particularly combined with digital video broadcasting (DVB) and the Internet explosion, will create a step-change in the way in which individuals communicate with each other and access and use information. The functionality, performance, and costs of these devices will be determined by key technologies. Significant component technologies that will simplify the use and reduce the cost of mobile devices include (1) display technologies, such as plasma display panels (PDP) and cholesteric liquid-crystal (CLC) screens, and (2) voice- and man-machine interface technologies, such as handwriting and voice recognition. It is clear, however, that more research needs to be devoted to the user interface if a mass market for mobile multimedia is to be achieved. In the longer term, holographic displays and natural language processing will make devices much more user friendly, though it is difficult to predict when these will become commercially viable. Taking into account the high processing power demand and the relatively flat projections for improvements in battery technology, it is possible that these more exotic user interface forms may be restricted to mains-powered environments.
Introduction 1.3.2
11
Compression Standards for Multimedia: JPEG, MP3, MPEG-4, MPEG-7
Compression technologies began their success with the achievement of digitized voice: Effective encoding algorithms were developed in order to transmit analog signals over digital channels. After the successful implementation of a number of encoding standardssuch as the full-rate, half-rate, and the adaptive multirate codecs for voice, the still picture JPEG, the moving MPEG-2, and the audio compression standard MP3new enhanced coding algorithms, particularly for low to medium bit rates on radio transmission channels with variable delay characteristics, are being developed. What are driving these developments are the limited amount of frequency spectrum available and the consequent requirement to minimize the amount of transmitted data. Dynamically changing traffic characteristics must also be taken into account. In addition to a number of companies developing their proprietary encoding solutions, both the International Telecommunication Union (ITU) and the International Organization for Standardization (ISO) are developing standards for video and audio coding for medium to low bit rate transmission. MPEG-4, developed by ISO for mobile and wireless multimedia communications, will be usable on cellular mobile and satellite systems. MPEG-4 was born out of the need for very low bit rates by high and efficient compression algorithms, particularly for mobile and wireless multimedia communications. It was originally targeted primarily at very low bit rates, but over time its focus broadened beyond just high compression. High priority was placed on the following key functions provided by MPEG-4 (which were not supported by existing standards): • Content-based interactivity: • • • •
Content-based multimedia data access tools; Content-based manipulation and bit stream editing; Hybrid natural and synthetic data coding; Improved temporal random access.
• Compression: • •
Improved coding efficiency; Coding of multiple concurrent data streams.
• Universal access: • •
Robustness in error-prone situations; Content-based scalability.
12
UMTS and Mobile Computing
The MPEG-4 algorithm supports efficient coding of multimedia video and audio data as individual objects. The improved power of MPEG-4 over its predecessors (MPEG-1 and MPEG-2) comes from its content-based functionality, which allows highly flexible access and manipulation of audio-visual (AV) objects in a very efficiently compressed domain. The video coding scheme of MPEG-4 is mainly based on the H.263 video-coding algorithm from the ITU. The basic configuration of H.263 is an extended version of ITU-T H.261. It is a hybrid of interpicture prediction to utilize temporal redundancy and transform coding of the remaining signal to reduce spatial redundancy. 1.3.3
Wireless Technologies Migrate to Configurable Radio and Smart Antennas
Configurable radio, or software-defined radio (SDR) [9], allows for the dynamic configuration of the radio parameters of mobile terminals and base stations (software radio). This technology enables a mobile user device to accommodate two or more air interfaces without additional hardware, and as such will be a key enabler for the third wave in computing. Configurable radio is a way of realizing multimode terminals, which can operate by software control in different frequency ranges and with different air interfaces; this may be a cost-effective means of developing global markets for terminal and infrastructure equipment, enabling manufacturers to gain from significant economies of scale. Downloadable applications and software intermediation by mobile agents promise to relieve the complexity barriers that make it difficult for users of todays computing equipment to understand their systems and to keep them up to date with new software. Potentially, these technologies may reduce the inherent complexity and cost of the terminal. In the longer term, artificial intelligence technologies promise self-learning and self-adaptive systems. The subsequent reduction in complexity of services and interfaces will break down the barriers that would otherwise prevent exploitation of the benefits of mobile multimedia services. Software technologies, such as artificial intelligence, fuzzy logic, and intelligent agents, are likely to be combined to provide powerful yet easy-to-use information and entertainment applications. The significant near-term impact of software radio will be in the field of service and applications innovation, which will use downloadable software applications as a tool to allow rapid and flexible service customization and
Introduction
13
new degrees of operator differentiation. As technology advances, it will become feasible to download software for increasingly lower layers of the protocol stackinitial commercial implementations of software radio are already beginning to happen. Technology enablers are shown in Figure 1.3; they include the following: • Analog-digital conversion and digital signal processing: low-power
high-MIPS2 products;
• Silicon capability: reducing geometries and operating voltages; • Real-time software download; • PersonalJava and the JavaCard: rapidly evolving portable software
technology.
Smart antennas are adaptive, which promises improved spectrum efficiency of mobile cellular systems. The aim of a smart antenna is to maximize the antenna gain in the direction of the user signal and to minimize the antenna gain along the direction of interfering mobile users. Smart antennas react intelligently to the received radio signal, continually modifying their
Digital DigitalRadio radio Technology technology
A/D performance Digital signal processing Increased processing power Increased memory capacity Low-power baseband controller Field programmable gate arrays
Software Software Technology technology
Realtime SW download Realtime kernel Virtual machine Frequency management Driver
Dynamic radio equipment reconfiguration by downloadable software at any protocol layer
Figure 1.3 Software-defined radio.
2. Million instructions per second.
14
UMTS and Mobile Computing
parameters to optimize the transmitted and received signal. This allows them to do the following: • Increase coverage and capacity by reducing interference between
adjacent mobiles;
• Offer space division multiple access (SDMA), where frequencies are
assigned on a per-mobile rather than a per-cell basis, allowing vastly increased capacity;
• Enable user location in space, allowing the introduction of advanced
location-based services.
Smart antennas may be used in two different ways: 1. As a spatial filter to reduce cochannel interference so as to increase the system efficiency by reducing the cluster size; 2. To reuse the traffic channels by beamforming more time inside the same cell. Figure 1.4 shows typical smart antenna characteristics with multiple beams; these will change dynamically. Mobile user Cluster 1
30
60
90
Figure 1.4 Smart antenna characteristics.
Mobile user 0
Cluster 2
−30
−60
−90
Introduction 1.3.4
15
The Internet, Intranets, and Mobility
Since 1992, both the Internet and mobile networks have had a dramatic impact on nearly all facets of modern life. They will certainly continue to restructure the business value chain for many of the traditional services and processes that we currently use. Thus, it can be safely said that the Internet and mobile development will have a great impact on the future. The Internet, which today is a heterogeneous network that deals mainly with e-mail and information content, is perhaps the most significant technology driving a general understanding of and familiarity with IT interfaces, such as the PC, as well as societal acceptance of information technology. Future generations of the IP, including IPv6, will combine wireless access and content-based services even further. Many articles have been written on the Internets so-called last mile problem, which appears to be the bottleneck with regard to bandwidth and accessibility by residential and business users. To meet this challenge, wireless access technologies were developed that provide two-way communications with increasing bandwidths. In recent years, the first release of the Universal Mobile Telecommunication System (UMTS) [10] was developed to enable mobile multimedia. Its impact on multimedia services and interface design will be considerable and will be realized in terms of increased applicability of mobile computing, personalization, ease of use, wide availability of and access to global services, as well as improvement in the general level of IT literacy through greater exposure to the Internet and intranets. The convergence of UMTS with the Internet will encourage Internet applications development with a strong focus on mobile services and will probably change the Internet dramatically. The worldwide perception initiated through the ITU vision of IMT-2000 is that wireless cellular systems and the Internet will take personal communications to the Information Society by delivering voice, graphics, video, and other broadband information direct to the user. These systems will move mobile communications forward from 2G systemswhich have created a mass market for mainly voice-based digital wireless services between 1990 and 2000to encompass fully multimedia services. Mobile multimedia communication services will provide both terminal and service mobility on mobile networks, taking advantage of the convergence of existing and future fixed and mobile networks and the potential synergies that can be derived from such convergence. If new systems and devices are able to learn and adapt to suit the environment and user needs (as a result of developments in artificial intelligence), the subsequent reduction in complexity and
16
UMTS and Mobile Computing
reduced costs of devices and services could open telecommunications markets up to almost limitless possibilities for service variety. 1.3.5
Services and Applications
Making the Internet mobile is not just about adding a wireless access technique to the existing infrastructure. Mobile Internet goes far beyond this and will include the addition of a number of service enablersmobility, user identity and security, location information, and personalizationwhich will also improve the existing Internet. Such attributes will make a mobile Internet possible, with inherent new service capabilities and new business opportunities. Anywhere and anytime describe a situation-, location-, and person-driven multimedia infrastructure with devices that will lead us to the achievement of mobile computing.
References [1] Weiser, M., The Computer for the 21st Century, Scientific American, UC paper, September 1991, http://www.ubiq.com/hypertext/weiser/SciAmDraft3.html. [2] Weiser, M., http://www.ubiq.com/hypertext/weiser/UbiHome.html. [3] Weiser, M., and J. Seely Brown, Xerox PARC, The Coming Age of Calm Technology, October 1996, http://www.ubiq.com/hypertext/weiser/acmfuture2endnote.htm. [4] Southport Retravision, http://www.southport-retravision.com.au. [5] Margherita2000, http://www.margherita2000.com/sito_uk/it/home.htm. [6] Texas Instruments, TINI, http://www.iButton.com/TINI. [7] Pratt, V., Matchbox Server, http://wearables.stanford.edu. [8] Cell Computing, http://www.cellcomputing.com. [9] Buracchini, E., The Software Radio Concept, IEEE Communications Magazine, Vol. 38, No. 9, September 2000, pp. 13843. [10] UMTS Forum, UMTS Forum Report No. 1, A Regulatory Framework for UMTS, UMTS Forum, 1012 Russel Square, London WC1B5EE, United Kingdom, October 1999.
2 The Market for UC 2.1 Mobile Market Developments Wireless mobile networks have a clear lead over the Internet in terms of penetration [1]. Although today the network infrastructure is still mainly voice-related, every mobile device represents a special-purpose computer that provides a variety of functions, including data services like short message service (SMS). Technology innovations will change these devices over time, making them ever more like mobile computing devices that access the Internet. Even the mobile networks themselves will be IP-based in future. It is expected that by approximately 2010 more than 50% of the mobile devices used in cellular networks will provide Internet-based services. The wireless market not only comes from analog and digital conventional telecommunications network markets, it is also a new market. The traditional telecommunications market was dominated by one product: voice communications. The mobile networks emerged later and took advantage of the existing market in the sense that the first mobile phones were able to communicate with hundreds of million of phones on the fixed networks globally. Later, the mobile market evolved with the provision of international roaming, a unique feature making the mobile user communication independent from its location, providing reachability anywhere and anytime. Still later, the mobile networks changed from an environment dominated by voice to one where text messaging and enhanced data services are equally important. The new Internet market seems to have developed in a similar way as the fixed telephone network market in the past: Wireless mobile access to the Internet for e-mail and Web applicationsboth dominating in the current 17
18
UMTS and Mobile Computing
Internetwill be key to launching the mobile Internet. After having reached a critical mass market size for new mobile Internet services, the market could emerge on its own and become an even greater factor than the original Internet market. The forecast in Chapter 1 indicates such developments. Of course, the transition to the mobile Internet also requires new service concepts and an in-depth understanding of the new user. Customer segmentation focusing on customer value and availability of services at the right price will be key factors to success. Additionally, content needs to scale to the various display sizes of different terminals and also requires end-to-end interoperability in order to ensure wide end-user acceptance. Figure 2.1 shows the development steps of wireless terrestrial cellular technologies, also called generations. First were analog technologies, which allowed voice services only. Second-generation technologies next began to offer text-based data servicesthe SMS is a successful example. Internetenabling network technologies were developed on top of the 2G systems: Wireless application protocol (WAP) [2, 3], i-mode [4], general packet radio service (GPRS), enhanced data rates for GSM evolution (EDGE), and upgraded IS-95 technologies are typical examples. The question that is often asked is what is the motivation for a 3G system, such as UMTS? Current market analyses suggest that in addition to evolved 2G mobile services, such as GSM, there is a need for a new generation wireless wideband system with characteristics, such as video, multimedia, flexible service provision, bit rates of up to approximately 384 Kbps for wide area, universal coverage and vehicular speed, and up to 2 Mbps for local area coverage. UMTS [5] will meet these demands according to its specifications, which are laid down in the ITU-R framework standards. UMTS at the outset was seen as the convergence of wireless local loop, cellular mobile, paging, private mobile radio, and other 2G applications. It has evolved, however, into a system that will take the personal communications user into the new information society by providing higher bit rate data exchangethat is, broadband multimedia capabilities and convergence with the Internet. As the wireless market moves towards multimedia, operators will need to ensure that the subscribers using such services are effectively supported wherever they happen to be located (roaming). Mobile data applications are commercially viable today, but future mobile network enhancements will enable operators to offer a broader, more profitable range of (multimedia) applications and services. Current offerings from cellular network operators include information on stock prices, weather forecasts, sports, traffic, and other Internet content
1G systems
Trunked mobile radio
Microwave point-tomultipoint
2G systems
Analog cellular
Trunked mobile radio
3G systems
Digital cordless
Digital cellular
Local area
TETRA (Europe)
CT2 DECT (Europe)
D-AMPS CDMA (USA)
Bluetooth DECT+
AMPS (USA)
TETRA POL (Europe)
PACS (USA)
GSM (Europe)
WLAN HIPERLAN2 BRAIN
iDEN APCO25 (USA)
PHS (Japan)
PDC (Japan)
Proprietary systems
IMT-2000 UMTS CDMA 2000 UWCC
The Market for UC
NMT TACS (Europe)
Wide area cellular
Proprietary systems
19
Figure 2.1 Wireless terrestrial cellular technologies.
20
UMTS and Mobile Computing
for mass markets, most of which are developed by WAP content providers. The success of the i-mode [4], described in Chapter 5, has been driven by its early entry into the market, as well as by the development of content by more than 3,000 information providers. The rapid growth and current penetration of this service (some 30 million subscribers) has demonstrated the acceptance of data services in future networks. There are a number of reasons why WAP has not yet been as successful as i-mode: the business model, the circuitswitched transport, the markup language WML, and user behavior. The key enabler for the mobile data consumer mass market is the packaging of applications and presentation of content within an easy-to-use terminal device. This captures the imagination of the consumer in the same way that the latest generation of mobile handsets and tariffs combined with voice messaging services has driven the wireless voice markets. These enable previously unconscious and undefined, or wholly new, user needs to be identified and satisfied; this process results in the creation of completely new, previously unknown classes of services. The next generation of mobile terminals is expected to come in steps with increasing bit rates towards multimedia (voice, data, text, image, and slow scan video) and based on a combination of functions seen in the notebook, handheld, and mobile phone. This means that for 3G services and applications, a variety of mobile terminals designed on a new data platform and targeted at various market segments will emerge, with voice as one of the features. It should come as no surprise to learn that the number of Internetcapable mobiles will soon outnumber the quantity of Internet-capable PCs. The growth rates of PCs sold to the marketplace are tending backwards, already indicating a saturation in developed regions. This could have a strong impact on the development of the Internet itself (IPv4 versus IPv6). There is a belief that the introduction of mobile Internet services will accelerate the already rapid growth of both mobile and Internet services: convergence. Figure 2.2 shows the forecasts for mobile subscriptions in 2G and 3G mobile networks. 2.1.1
Emerging Wireless Personal Area and Wireless Local Area Networks
The market developments of digital enhanced cordless telecommunications (DECT) and the Personal Handy Phone System (PHS, Japan) in the last decade indicated increasing demand for systems with limited mobility [e.g., in the home and office environment, and partly also in the public environment (PHS)]. The systems were predominantly seen as for voice applications
The Market for UC
21
World (total) 2
Mobile users
2 15
15 1
500
730 260
1990
650 500
285 185 2000
Asia (+RoW) 900
350 2005
560 540
Europe
N/S America
2010
Figure 2.2 Forecasted wide area mobile network markets. (Source: Siemens.)
related to wireline corporate or public networks [public switched telephone network (PSTN), integrated service digital network (ISDN)]. Roaming with wide area mobile networks has not taken place, although market success was quite highmainly in Japan with approximately 20 million PHS units, and in Europe with more than 100 million DECT units [6]. The equipment was also upgraded for data applications. Increasingly, new technologies will come onto the market, and these will be more focused on data applications and will offer higher bit rates and IPs in short-range scenarios. In addition to DECT, which was accepted as a 3G ITU standard with its improvement to 2 Mbps, new technologies like Bluetooth and wireless local area networks (WLANs) will increasingly dominate in this market, mainly in the indoor environment. For WLANs, roaming with wide area mobile networks is under discussion. Some manufacturers offer proprietary solutions already. The forecasts for WLANs worldwide indicate between 10 and 20 million units in 2005 [7]. In contrast to the licensed public networks, the regulatory conditions for this market with general allowances for, say, equipment use, give far more flexibility to the industry to operate networks successfully and to compete with products in various environments. The frequency spectrum is usually allocated for license-exempt use in order to allow self-provided networks. There is a relatively large spectrum available in the 2.4- and 5-GHz range. The DECT/PHS- and UMTS-bands account for approximately 50 MHz of bandwidth; the industrial-scientific-medical (ISM)
22
UMTS and Mobile Computing
band is 83-MHz wide, and the 5-GHz bands for WLANs provide 200 to 400 MHz of bandwidth. Self-provided mobile networks and wireless radio access systems are usually personal or local area or corporate or regional networks typically for low mobility or semistationary use. They are in service in a number of countries around the globe. There is no clear technology winner in this market, because there is no real need for a common standard like in mobile cellular networks, which require worldwide roaming. The relevance of some technologies in connection with wide area mobile networks, however, should not be underestimated. For example, the value of Bluetooth as a complementary interface to cellular radio could play a significant role in the future. WLANs and high-performance radio local access network (HIPERLAN) are primarily considered as radio local area networks (RLAN) or as wireless local loop systems. There are also private mobile radio (PMR) systems with larger radio coverage (city) for emergency services (police, rescue) and for closed user groups (such as taxi drivers). These networks undergo technology changes that provide voice and data services. Integrated digital enhanced network (iDEN), the American Police Communication Organization (APCO) 25 in the United States, and trans European trunked radio (TETRA) and TETRAPOL in Europe are examples of 2G trunked-radio systems. 2.1.2
Mobile Satellite Network Markets
Satellite communications were once seen as a serious threat to the terrestrial mobile market, but now they are viewed only as a niche technology. There are only a few new projects to be seen in the future, like Globalstar, ICO, and Teledesic. The largest network in terms of subscribers is the Immarsat network with approximately 300,000 users.
2.2 Internet Market Developments All the major players in the IT industry are betting significant amounts of money on the successful transformation of the Internet into a pervasive mediumconnecting users to personalized universes of dynamic content, applications, and services, via any smart, connected device. Pervasive computing, however, is about much more then connectivity. It is the final step in the transformation of computing from a single resource to a technology with distributed resources and democratized access. The price of admission to this
The Market for UC
23
market is a secure, reliable infrastructure that can scale to a large number of network-connected devices either stationary or mobile. The Internet was in existence for about three decades before it entered the current phase of mass-market acceptance. The trigger was the introduction of interfaces, such as Mosaic and the Web, which transformed the Internet into a user-friendly environment. Another important development was the introduction of mass-market applications, such as spreadsheets and word processing. Until such time, the PC was merely a cheap alternative to minicomputers. As shown in Figure 2.3, the origin of the Internet, after the first research work from Kleinrock, lies in the ARPANET, which was born in a military laboratory in 1969. The aim was to allow computer scientists and engineers working on military contracts all over America to share expensive computers and other resources. E-mail, as it became known, quickly turned the network into a communications medium. Until 1983 the Internet consisted of fewer than 500 host computers, almost exclusively in American military labs and academic computer-science departments. But the word was getting out to other academics. By 1987 the Internet had grown to include 28,000 host computers at hundreds of different universities and research labs around the world. No other method for networking universities around the world was so universal and so flexible. The Internet as a heterogeneous network was adaptive for all kinds of access and carrier networks, private or public. Users invented ways for many people to participate in open discussions; they created software and document libraries on the network and made them accessible to all. During the late 1980s, while the Internet was growing in the academic world, a networking revolution of another sort was taking place in the business world. Businesses realized that, having traded their mainframes for a multiplicity of PCs, they needed some way to recapture the mainframes ability to share data and devices, such as printers. So they strung wires around their offices and connected the PCs together. The IP was used in these networks, and it became a de facto world standard. These local area networks (LANs) did more than save money; they changed the way people worked. E-mail took off within offices and, soon, between them, as companies created wide area networks (WANs) to connect distant workplaces. But there it stopped. Different software and hardware standards used by different companies made creating wider networks a nightmare of incompatibility. Again, the Internets applications, predominantly the Simple Mail Transfer
24
JAVA WWW (CERN)
TCP concept USA, England, Hawaii
*
TCP/IP standard
1 billion Web pages
100200 million servers
43 million servers
New domain names
ICANN domain names
Internet rollout
Name server
23 billion Web pages
150 million users
300 million users
400 million users
1998
2000
2001
ARPANET concept/operation
1968
1969
1974/75 *
1983
1986
1990 1991 1995
ARPANET: Advanced Research Project Association Network/Department of Defense USA ICANN: Internet Corporation for assigned names/numbers
Figure 2.3 The Internet.
UMTS and Mobile Computing
NSFNet 10,000 hosts
100,000 hosts
300 million Web pages
The Market for UC
25
Protocol (SMTP), the File Transfer Protocol (FTP), and the Hypertext Transfer Protocol (HTTP), provided the necessary compatibility. In homes, PCs had made computer power affordable, and modems had allowed them to be connected over telephone lines to commercial on-line services and bulletin boards (electronic discussion groups and software libraries usually set up by enthusiasts). Both of these grew steadily, but not explosively. Each had disadvantages. The networks offered by CompuServe, the leading on-line service provider, and others were national, even global. In mid-1993 something new happened: The Internet sprouted multimedia wings. A combination of special software and a way of connecting documents allowed users to travel the network with pictures, sound, and video, simply by pointing and clicking a mouse. Suddenly, the Internet was not just a way to send e-mail and download the occasional file. It was now a place to visit, full of people and ideas: It was cyberspace. It was a new medium, based on broadcasting and publishing, but with another dimension added: interactivity. Internet veterans had known this for years; they could see the potential behind the screens of plain text and baffling computer commands. But thanks to the Web, the friendly, multimedia side of the Net, a much broader audience started to catch on to it. Since 1988 the Internet as a whole has doubled in size every year. In 2001 it reached 100 to 200 million host computers, each having the capacity to connect several individual users. During the same period, the Web grew as fast: In just 10 years, from 1992 to 2002, users created more than 2 billion Web pages containing information, entertainment, and advertising. No one knows how many people have contributed to this growth. No communications medium has ever grown as quickly; nor has any other electronicsrelated market. Figure 2.4 shows the wireline Internet growth forecasts (they will probably be surpassed by mobile Internet by 2008 because of the expected tremendous growth on the wireless side). 2.2.1
Challenge: Transition from Circuit Switching to Packet Switching
The rise of the Internet initiated interesting changes in the global telecommunications infrastructure thinking. Computer interworking was originally based on leased lines or on accessing the public telephone network. Over time, data networking based on IP became its own infrastructure; a heterogeneous network called the Internet came into existence. Internet traffic doubles every 6 months now, and it is still mainly data trafficvoice traffic is only partly transported via the Internet and will remain as such in the future. Merged voice and data will emerge in multimedia.
26
UMTS and Mobile Computing
600 Internet users
Internet users/hosts
500
Internet hosts ~ 400
400 300
200
200 100 100 50 1990
50
10
1995
20
>200
>100 56
2000
2005
Figure 2.4 Internet growth.
A typical characteristic of the Internet is that data is split up into packets, which do not need a line exclusively for themselves. Packets from hundreds of sources are mixed up by the computer and shoved into a pipe (either the transmission line or the air interface). The router at the other end of the line receives each one, reads its address, and sends it in the right direction. All packet-switched networks follow this principle of data transmission and routing, most of them using the IP protocol. Finally, the server receives the packets from many sources, usually with a far higher bit rate than if transmitted from a single source, and reassembles them appropriately. A main advantage of the packet-switched mode is that the end-to-end user connection is established as a virtual connection, which allows the user to be in an always-on mode. Many new services need such a function, because it saves network resources (e.g., frequency spectrum, transmission capacity) by providing the simultaneous use of a physical line or a frequency channel by transferring packets corresponding to virtual calls. The connectionless IP provides the flexibility for multiservice transport and switching that is important for multimedia. In multimedia communications, several virtual connections have to be managed at the same time. In the circuit-switched mode, which is used mainly for voice connections, the entire bandwidth of the individual channel is dedicated to one
The Market for UC
27
connection for the duration of a call: This is a physical connection. After clearing the call, the channel remains free until another connection is set up. The transmission bit rate remains constant throughout the connection. The exclusive use of a channel guarantees quality of service like throughput and short and constant delay time, but this can tax the total capacity utilization of the system. It consumes resources used to prevent blocking, especially in cases of bursty traffic and long session durations. It is therefore inefficient for always-on applications. The circuit-switched telephone system was designed specifically to satisfy the human ear. The same goal was valid for the mobile networks in their beginnings. Nowadays, with data communications, the advent of packet switching, and the multiplicity of different traffic bit rates, there is more than one set of criteria to satisfy. The data rate needed for voice communication is intolerable for transferring high-resolution images or audio and video with satisfying quality. Conversely, the degree of network latency may not be adequate for real-time voice or video and audio streaming. Quality of service (QoS), therefore, becomes an important topic for packet-switched infrastructures. The most important quality of service requirements are the availability of the network, the throughput defined in bits per second, the latency (which is for voice less than 150 ms), the jitter, and the packet-loss. The sensitivities of services and applications vary depending on traffic type. To cope with the varying requirements, the new approach of multiprotocol label switching is increasingly applied to the infrastructures. 2.2.2
Internet Access from Mobile Devices
As the penetration of Internet, mobile phone, and portable computer usage increases at rapid and parallel rates, it is easy to conclude that their futures will become integrated. Today 75% of wireless phone users in the United States also access the Internet via their PCs. They probably wish to have access to the Internet via their mobile phone as well. Internet access includes e-mail and file transfer services, chat, voice over IP (VoIP), Web browsing, and retrieval of specified information that may be provided on an ongoing basis via a Web-based information service. Table 2.1 shows the percentage of services used in the Internet in 2000. For mobile users, this could include information that is relevant to traveling, such as timetables, traffic updates, hotel and restaurant listings, or urgent data, such as meeting schedules and stock prices. With wireless access to the Internet, the roaming user comes into play. The personalization of information will become a new business factor. It will
28
UMTS and Mobile Computing Table 2.1 Internet Services Usage in 2000 Service
Application Protocol
Usage (%)
Traffic (%)
E-mail
SMTP
97
4
WWW
HTTP
95
65
File transfer
FTP
78
15
Blackboard
NNTP
41
1
Chat
CAT
33
15
Telephony
SIP
24
15
increase both the value of information to the consumer and the level of business for the operator. The greater the value, the more willing the user will be to pay for the service. Information services that respond to users needs and give them choices will be compelling. For example, when driving in an unfamiliar area, motorists may value information location for the cheapest gas station within 2 milesinformation that can lead to a mobile commerce transaction if the gas is purchased via the debit card on the mobile phone. This type of service includes two important ingredients for success: • Personalization: providing user-specific content; • Localization: transmitting information to users according to their
geographic location.
2.2.3
The Web Market
The Web was invented in 1991 by CERN.1 By the end of 1994 about 4 million Internet users had the right connections to use the Web. The Web is unquestionably the fastest growing part of the Internet. Today, Web browsing is the leading Internet application, together with e-mail, followed by entertainment and work. It is the Webwith its multimedia gloss, interactivity, and emerging secure areasthat most companies would choose as their Internet marketplace. More than 2 billion Web pages already exist currently in the worlds Internet market. 1. CERN created the idea of Web sites. The first premiered at Stanford University on December 12,1991.
The Market for UC
29
The biggest market for the Internet is information, advertising, and marketing, and business is already thriving in these areas. Most of the corporate home pages on the Web amount to little more than the usual marketing gloss, polished to an extra shine by electronic means. E-commerce-enabled Web sites facilitate the buying and selling of goods and services, the processing and authorizing of purchase transactions, and, where possible, the digital distribution of the product. E-commerce will be the cornerstone for mobile commerce. 2.2.4
Electronic Commerce: A Fundamental Component of Future Multimedia Services
Growth in electronic commerce over the next 10 years will continue to drive automation in the retail and finance sector, the growing penetration of PCs at home and in the office, the explosive growth of Internet and intranet hosts and users, and with increased familiarity with credit and debit cards, handheld shopping could be one of a number of revolutionary business changes. Financial institutions and retailers are experimenting with virtual malls, and although user acceptance of the Internet in promoting this trend is still uncertain, it is clear that a key driver of future multimedia services will be the demand for alternative, cheaper means of marketing and distributing goods and services. The success of multimedia services based on financial transactions is predicated on the ability of the industry to allay current user concerns about the security of Web-based transactions. The many facets of commerce include business-to-business (B2B), business-to-employee (B2E), and business-to-customer (B2C), where consumer behavior plays a critical part in its acceptance. The network operator, however, will first have to be content with a small transaction margin of new m-commerce businesses. Clearly, profitability in this case will be strongly dependent on volume (i.e., on the rapid creation of a mass market). 2.2.5
Intranet Need for Mobile Extensions
What the Internet has done for consumers, intranets are about to do for business. Intranets offer large organizations two distinct advantages that the Internet does not: 1. Security. Because intranets are inside inherently secure organizational networks, intranets can offer valuable information many companies simply would not want to make available to outsiders.
30
UMTS and Mobile Computing
2. Bandwidth. Intranets running on Ethernet, or even faster ATMbased networks are able to offer full-motion video, something most Internet users will not experience for a while. 2.2.6
Intranet Access from Mobile Devices
From a security point of view, it is more critical for a business user to connect to their corporate LAN or intranet than to a public Web site. Corporations are rapidly deploying intranets and enabling remote access to them from outside the firewall so that users can gain access to corporate information and databases like price lists, stock availability, order entry, customer records, the corporate directory, or collaborative work-group applications. For mobile executives with electronic organizers, the ability to manage remotely an address book and diary is important. Synchronization of the organizer contents with the main personal information manager on the users desktop PC will be critical.
2.3 Fixed and Mobile Convergence As the Internet grows, so does the market for wireless communication devices. Such devices will increase the options for making connections to the global Internet. Mobile customers can already find a wide variety of such wireless devices available. There are numerous radio attachments and infrared devices, and, of course, communications by way of the cellular network is always an option for those willing to pay the fees. The provision of multimedia services in a mobile environment merges several formerly independent markets: computing, (mobile) communications, photography, video and audio processing and presentation, music production, and distribution. Mobile communications is increasingly becoming a multimedia environment that will be no longer limited to two-way voice and low-medium rate data services. The multimedia environment will extend the provision of several high-rate audio, video, and data services that are now only available through wireline networks. The concept of the mobile voice call will be radically changed as multimedia components are added. Data, speech, audio, and images can simultaneously be shared with users who are connected with a speech or video connectionleading to more effective visual communications. In addition, the convergence of voice and data is taking place in the mobile environment with some significant advances in technology. The price for mobile data transmission is going to decline in the next few years while the speed of transmission goes up. People
The Market for UC
31
will be fully mobile and able to access and use information in data-based applications around the world. These trends are generating a great deal of interest in making sure that mobile wireless computers can attach to the Internet and remain attached even as they move from place to place, establishing new links and moving away from previously established links. The combination of Internet technology with mobile connectivity holds out the prospect of the marriage of two of the biggest and fastest growing markets in telecommunications. Key challenges to the mobile supply community over the next decade will be to overcome the problems that this combination poses and to develop packages of services, terminals, and applications that will delight users. This process of convergence has widened to include the field of broadcasting, where much content is produced and distributed via transmitter stations on satellites or the ground or via cable, but also via bi-directional channels like the Internet and mobile Internet (e.g., video on demand). Such convergence can be seen in upcoming distribution networks for DVB and digital audio broadcast (DAB), as well as in the Multichannel Multipoint Distribution System in the United States. The underlying concepts for these networks have evolved to include elements of interactivity. This results in an asymmetrical traffic distribution with high capacity for information download and low capacity for the return channel upload, thus providing a certain degree of interactivity. Business opportunities lie in education and learning, location-based services, infotainment, and elsewhere. Figure 2.5 shows UMTS as the provider of such service convergence in the fields of telecommunication, Internet and computing, and information media. Because the wireless Internet is an unprecedented phenomenon and the required business models and strategies are yet untested, market estimates vary widely, and entry into this market is often associated with risks. There are, however, indicators that provide evidence of its great potential. 2.3.1
Mobile Computer-Based Communications and UMTS
It is conceivable that by 2003 the number of Internet and intranet users will be 500 million worldwide, making it potentially possible for a user with an Internet-capable mobile device to communicate with a mass market base of 500 million fixed Internet users. On the mobile network side, already more than a billion users are estimated to be in the worlds marketplaces. The mobiles will be data-enabled to a large extent. This means that nearly any
32
UMTS and Mobile Computing Internet/Intranet E-Mail WWW IP Protocols E-Commerce
Broadcast media Audio-video on demand Infotainment/education TV and radio distribution Multipoint distribution
UMTS
Telecommunication Realtime connectivity wireless Mobility/roaming/person location Voice, SMS, fax, data
New technology Broadband radio access Smart antenna Circuit-packet-switched transport Multimedia HW, SW Compression techniques
Figure 2.5 UMTS provides convergence.
kind of terminal will be capable of using the Internet in a more or less limited way. By the end of the decade, the PC will be only one amongst several different terminals for home access to the Internet, along with televisions, network computers, mobile terminals, and handheld games units. As a result of these developments, most fixed networked multimedia services, including information and entertainment services, will likely be packet switched with IP and will have asymmetric handling. This will have significant implications for delivery systems for mobile multimedia services, such as UMTS and IMT-2000 [5], because it implies that many mobile multimedia services will be IP-based. This underpins the expectations for the mobile multimedia marketplace and is supported by evidence of three key trends: (1) the increasing mobility of individuals, whether as employees or as individuals; (2) the increasing requirements for responsiveness in business; and (3) the growing demand for communications and access to information while on the move. 2.3.2
Increasing Mobility of Individuals and the Pressure to Turn Dead Time into Productive Time
The worlds urbanization is still rapidly increasing, and large cities are getting bigger and bigger, especially in underdeveloped countries, but also in
The Market for UC
33
developed countries. Consequently, many individuals are spending more time traveling, whether for commuting or for pleasure, thus creating significant growth in dead, or unproductive, time in the workday. Meanwhile, increasing competitive pressures are forcing businesses to increase the productivity of their employees, thus placing greater demands on their time and creating a need to make dead time more productive. The increasing popularity of portable computing devices provides evidence that more workers, particularly those in knowledge-based industries, are becoming more mobile, working remotely from their normal base, and making better use of otherwise dead time.
2.3.3
Key Enablers
Industry players (operators, equipment suppliers, and regulators) will play a significant role in contributing to the development of the market. Positive actions on their part will encourage market take-up through the development and delivery of services that users find affordable, easy to use, and well matched to their needs. The most significant issue that will enable strong market development will be the nature of the regulatory environment governing access to the underlying network infrastructure and the delivery of services over that infrastructure. This framework will be fundamental in determining whether new service providers and their backers find this market easy to enter. This in turn will determine the intensity of competition within the market. It will be crucial for the success of mobile multimedia that service providers obtain costeffective access to mobile networks on fair and reasonable terms. A second fundamental issue enabling market development will be the worldwide acceptance of a harmonized 3G mobile radio standard. Success in achieving this, as opposed to many regional standards, will enable the rapid development of the market through the creation of large terminal and infrastructure equipment markets, which will lead to a reduction in the cost of terminals and network infrastructure. Additionally, roaming agreements will give confidence to the consumer that their purchasing decision is a sound one, and that the terminal purchased will not be superseded by another incompatible system in a short period of time. The development of open standards for service and application development, perhaps using a de facto approach along the lines of the Internet standards model, will also facilitate market development by enabling rapid innovation, simplifying service creation, and ensuring service portability.
34
2.3.4
UMTS and Mobile Computing
Broadband Wireless Convergence
The unique advantages for the 3G mobile services are identified as high bit rates (for information services), always-on access, mobility, and global roaming. With these unique advantages it was forecast that wireless WANs could become the preferred method of access to the information society in the home, office, and public spaces. Since then, however, there have been major developments elsewhere which have enriched this unique opportunity: the WLAN and wireless personal area network (WPAN) systems. Their main disadvantage, however, is that roaming is very limited. There are currently two major technological trends, with a third likely to emerge. The first of these is based on WLAN technology [810]: the Institute of Electrical and Electronics Engineers (IEEE)2 802.11 WLAN and the HIPERLAN, both of which have a better mobility capability and bandwidth. HIPERLAN has been merged with the previous European Telecommunication Standards Institute (ETSI) Broadband Radio Access Network (BRAN) project. These broadband wireless access systems are seen now as enhancements in the scope of digital mobile systems, particularly the technologies from 2 Mbps up to bit rates of 11 and 22 Mbps with restricted user mobility and for picocell environments. The second trend is that of Bluetooth, which is a very low-cost wireless link that will become ubiquitously integrated into mobile devices like phones, portable computers and organizers, as well as vehicles, accessories, and peripherals. The Bluetooth industry has realized that this complementary technology can be adapted to provide relatively fast access. It is expected in the future that the Bluetooth and the WLAN technologies will provide a much higher capability than either does today. The third trend is the wireless home network, a relatively new proposal from the DVB community. This group is looking aggressively to take over the home space by combining cable, satellite, and terrestrial broadband delivery with wireless distribution about the home in order to provide for entertainment, telecommunications, and information. All these technologies are considered as elements for convergence with fixed and mobile wide area communication networks. While they do 2. The IEEE is a nonprofit, internationally recognized, independent association with more than 330,000 individual members in 150 countries. It promotes the engineering process of creating, developing, integrating, sharing, and applying knowledge about electro- and information technologies and sciences. The IEEE produces 30% of the worlds published literature in electrical engineering, computers, and control technology, holds annually more than 300 major conferences, and has more than 800 active standards with another 700 under development.
The Market for UC
35
not provide the full dynamic mobility of cellular, they do provide for nomadicity, enabling a user to automatically connect to his home network from different access points. For information services, full mobility may not be as essential as it is for a mobile phone where 100% coverage is essential. For intranet and extranet access, WLAN technology can provide services for nomadic users in offices, airport lounges, and conference centers. While for infotainment, Bluetooth could provide access for such things as music download, cinema booking (with added video clips), and other m-commerce from booths in shopping areas, airports, petrol stations, and supermarkets. The revolution of convergence with mobile WANs has already commenced. The cost of a WLAN card is several hundred U.S. dollars, and it operates in a radio frequency band that does not require an operator license. The costs of Bluetooth will eventually add only a few dollars to the cost of its host product. 2.3.5
Broadcasting Convergence
Some investigations have already begun to identify the synergies in this field. It is clear that broadcasters now own tremendous amounts of useful content that will become so important to customized infotainment services. It is also well known that many people access broadcast content via the Internet and potentially could do so via mobile broadband systems. Broadcasters also own very broadband frequencies, which are not always fully utilized. There has been some use of these broadband channels as Internet return channels already. Currently, there are discussions on using the global system for mobile communications (GSM) or UMTS and combining them with digital broadcast systems like DAB and DVB. The GSM/UMTS channel would allow the user to order information via a DAB or DVB radio broadcast network and manipulate the information received. This does not necessarily have to be an integrated terminal solution; a handheld combined with a TV set using different infrastructures but a common AV management could be quite feasible and economical. 2.3.6
Convergence on Devices
Convergent services, of course, will impact the device side as well. Ongoing developments signal the trend towards both multifunctional and specifically tailored solutions. Multimode terminals useable in a number of different systems standards will handle the complexity of multisystem standards. The emergence of new terminal categories will be further enhanced by dramatic
36
UMTS and Mobile Computing
improvements in connectivity between various devices. The cellular phone will act as a gateway to the world for other personal devices (e.g., PCs, PDAs, and digital cameras). Naturally, some of these functionalities will be integrated with the mobile phone, as in todays communicators, to complement a modular approach. A key to this enhanced connectivity will be Bluetooth technology and the 3G wireless technology UMTS. 2.3.7
Convergence and the Creation of New Services
The convergence of technology, as well as globalization, e-trade, and e-commerce are drivers for the creation of new services, which will come from the synergies in the formerly separated fields of services, applications, and technologies. Examples are the upcoming services that combine location information of a user or device with useful information from the location area: location-based services. Other examples are in the field of automobilerelated communication, Telematics and Telemedicine, and virtual team support. In addition, personalized access is another attribute that will impact new services in the future.
References [1] UMTS Forum, UMTS Forum Report No. 10, Shaping the Mobile Multimedia Future, UMTS Forum, 1012 Russel Square, London WC1B5EE, United Kingdom, October 2000. [2] WAP Forum, Frequently Asked Questions, http://www.wapforum.org/faqs. [3] Phone.Com, http://www.phone.com. [4] Kei-ichi, E., i-modeNow & Future Toward Mobile Multimedia in 3G, ITU Telecom Asia 2000 Proceedings, Hong Kong, December 49, 2000. [5] UMTS Forum, UMTS Forum Report No. 1, A Regulatory Framework for UMTS, UMTS Forum, 1012 Russel Square, London WC1B5EE, United Kingdom, October 1998. [6] DECT Forum, http://www.dect.ch; and Ericsson, DECT Overview, http:// www.ericsson.com/BN/dect.html. [7] Frost and Sullivan, 1999; http://www.frost.com. [8] HomeRF Working Group, http:// www.homerf.org. [9] HomeRF Working Group, SWAP white paper, The Shared Wireless Access Protocol (SWAP), http://www.homerf.org/press/hrfwgmkt.pdf. [10] IEEE, IEEE 802.16 Broadband Wireless Access (BWA) Standard, http://grouper.IEEEglobal.org/groups/802/16.
3 Technologies This chapter will give an overview of UC-enabling networking technologies and devices. It will describe technologies for wireless and mobile communication, and for the networking of mobile devices in wireless communication networks. Wireless networks in the local, regional, and wide area are considered in Section 3.1. Section 3.2 focuses on UMTS as the convergent system for mobile communications and mobile computing. Section 3.3 is dedicated to small information appliances, also called devices, that work in UC environments. These can be off-line, wireless, or wireless combined with wireline networked devices. Some example applications and scenarios of those devices are presented in order to describe their major uses. The technologies and devices that the authors think have more business value and are more impact to the UC era will be described in greater detail.
3.1 Mobile Wireless Communication Technologies This section describes the various mobile wireless communication technologies and networks. Such networks enable mobile devices and mobile computers to communicate wirelessly with one another and to access wireline networks like the Internet or various intranets. The term wireless refers to a communications, monitoring, or control system in which electromagnetic or acoustic waves carry a signal through atmospheric space rather than along a wire. In most wireless systems, radio-
37
38
UMTS and Mobile Computing
frequency (RF) or infrared (IR) waves are used. Some are used as monitoring devices, such as intrusion alarms; others employ acoustic waves at frequencies above the range of human hearing. Their typical bit rate is around 115 Kbps. Wireless communication technologies are understood as two-way communication technologies; they can be classified as follows: • Short-range radio systems: WLANs, wireless personal area networks
(WPANs), and home area networks (HANs);
• Medium-range radio systems: regional and wide area networks like
trunked radio systems, public cellular networks, point-to-point and point-to-multipoint systems;
• Long-range radio systems: extended area networks like high-altitude
platform stations and mobile satellite systems.
Figure 3.1 gives an overview and positions the various radio technologies in relation to range and bit rates. As Figure 3.1 shows, bit rates are generally high in short-range radio systems and go down in long-range radio systems. In contrast, mobility is low (50 km/hr) for short-range systems and goes up for long-range systems.
Mobility and cell range Global Long-range vehicular
100 km
Satellite
Medium-range vehicular 300m
2G TDMA CDMA
Short-range r = 1 km Pedestrian 100m indoor Personal area
3G CDMA UMTS BRAIN IEEE 802.11b HIPERLAN 2
DECT Bluetooth 0.1
0.5
2
IEEE 802.11a Hiperaccess 20
155 Mbps data rate per cell
Figure 3.1 Short-, medium-, and long-range radio technologies for bidirectional communications. (Source: Siemens.)
Technologies
39
Short-Range Radio Systems
There are a variety of technologies on the market, from infrared to WLANs. (These are not classified here into 1G, 2G, and 3G, although Bluetooth and WLANs are considered as complementary technologies to 3G.) The following technologies should be noted: • Infrared for very-short-range applications in one room (e.g., remote •
• • • • •
control, PC to mobile, one voice-data channel); Bluetooth for short-range applications (e.g., wireless PC, optimal headset, communications between PC and electronic organizer, home automation); DECT for short- and middle-range application; Home radio frequency systems for short-range applications; IEEE 802.11, 802.15 for short- and medium-range applications; HIPERLAN/2 for short- and medium-range applications; UMTS/time division duplex (TDD) for ranges of 300m or more.
Table 3.1 compares advantages and limitations of these technologies; they can be either complementary or competing. All these technologies cause interference. In a multicell environment, this can dramatically reduce the effectively transmitted bit rate and the cell radius. Some advantages of these different technologies are therefore reduced. Medium-Range Radio Systems
The Advanced Mobile Phone Service (AMPS) in the United States, Nordic Mobile Telephone (NMT) and total access communications system (TACS) in Europe and elsewhere, and JTACS in Japan are analog cellular systems that are still in use today. They permit two-way voice communications and circuit-switched data transmission, and AMPS, through an upgrade, permits cellular digital packet data (CDPD) services. CDPD, which is an overlay to AMPS, offers speeds up to 19.2 Kbps. Circuit-switched transmission sets up and keeps a circuit open between two or more users such that the users have exclusive use of the circuit (channel) until the connection is released. The development of digital technology resulted in the evolution to 2G technology. Time division multiple access (TDMA) standards are dominant here: IS-136 is the relevant U.S. standard; GSM is the European and worldwide accepted de facto TDMA standard. In Japan, another standard called
40
UMTS and Mobile Computing Table 3.1 Short- and Long-Range Radio Technologies
Technology Cellular
Effective Cell Radius Indoor/ Expected Level Outdoor of Penetration Advantages Resid.
Corp.
Limitations
Infrared
No
3m
High
Low
Price, no regulation worldwide
One room, line of sight
Bluetooth
No
10m
Low
High
Nearly all applications
1 Mbps, 8 active devices
Home RF/ SWAP
Yes
50m
High
Low
Combines benefits of 802.11 + DECT
Smaller cells due to EMI
802.1x
Yes
300m
Low
High
High rateup to 54 Mbps
EMI/lack of interoperability
HIPERLAN/2 Yes
200m
Low
High
Max. 25 Mbps QoS support
Price range
DECT
Yes
50/300m
High
High
Proven technique IMT-2000 member
Frequency band not in every country
Licenseexempt 3G (UMTS)
Yes
200m/2 km
High
High
IMT-2000 standard global roaming
personal digital cellular (PDC) was developed. Code division multiple access (CDMA) emerged as an alternative in the United States and Korea and led to the development of 3G systems called IMT-2000. Medium-range radio technologies provide low, medium, and high bit rate wireless access of up to 2 Mbps and more (see Table 3.2). The costs are dependent on the expected radio coverage across the country. Generally high mobility is the typical feature of cellular mobile systems like GSM, IS-I36, IS-95, PDC, IMT-2000/UMTS, and other specific systems for data applications. In addition, trunked radio technologies, such as TETRA and TETRAPOL, belong to these systems. High mobility means that the user
Technologies
41
Table 3.2 Medium-Range Radio Systems Effective Cell Radius Advantages
Limitations
AMPS, NMT, TACS, FDMA JTACS
50 km
International coverage
Analog voice
GSM + EDGE
TDMA
50 km
Global coverage, global roaming
Digital voice, up to 384 Kbps data
IS-136 + EDGE, PDC TDMA
50 km
International coverage
Digital voice, up to 384 Kbps data
IS-95
CDMA
50 km
International coverage
Digital voice, 56 Kbps
IMT-2000/ CDMA 2000
MCDMA
10 km
Global systems
up to 2 Mbps
IMT-2000/UMTS
WCDMA
10 km
Global systems
up to 2 Mbps
Technology
Cellular
can be on-line with his or her terminal and remain independent from the moving speeds of up to 200 to 300 km/hr. Automatic hand-off will transfer the user connection from one cell to the other. Second-generation networks are digital mobile telephone networks that offer mainly voice services, such as voice mail and caller ID, as well as the SMS. They are more secure than analog networks and offer greater network capacity. 2G networks permit packet-switched and circuit-switched data transmission at rates of between 9.6 and 14.4 Kbps and permit GPRS bit rates of up to approximately 115 Kbps. GPRS is the beginning of packet-switching transport in 2G networks, and therefore, it will have always-on features. GPRS implementation involves overlaying a packet-based air interface on the existing circuitswitched GSM network; the mobility management remains the same. This operation requires a new backbone network as well as a radio network upgrade. GPRS will also have sufficiently high bit rates in order to provide for Internet surfing. Packet-switching means that a GPRS radio resource is used only when users are actually sending or receiving data, as opposed to dedicating a radio channel to each user for a fixed period of time. This means that large numbers of GPRS users can potentially share the same channel bandwidth and be served from a single cell. The downside, however, is that all users in the cell compete for the same bandwidth.
42
UMTS and Mobile Computing
One of the problems with using various 2G technologies is their lack of interoperability. A GSM phone cannot be used on a CDMA network and vice-versa. Only a few dual-standard terminals exist on the market. In an effort to promote global service capabilities, the ITU promoted an initiative called International Mobile Telecommunications-2000 (IMT-2000), or 3G systems. Although UMTS is the most prominent standard in the framework of IMT-2000, one common standard did not emerge, and now there are five standards (see Section 3.1.3.2) on the radio and two on the core network side. The main criterion for compliance with 3G standards is data access with speeds up to 2 Mbps for quasistationary use (low mobility), 384 Kbps for medium mobility up to 120 km/hr, and 144 Kbps at traveling speeds of 500 km/hr (high mobility). Long-Range Radio Systems
High-altitude platform stations and satellite technologies are seen today mainly as a complement to terrestrial mobile radio networks for extending to areas with low population density. As GSM approaches worldwide radio coverage, it is now more efficient and cheaper to use a triband handheld that can roam from country to country than it is to use terrestrial networks. A similar situation will appear in the future with the establishment of IMT-2000/UMTS. There are four main types of long-range radio systems. They can either be satellite-based or high-altitude platform stations (HAPS). Table 3.3 shows how these systems compare with their terrestrial counterparts.
Table 3.3 Long-Range Radio Technologies GEO
MEO
LEO
HAPS
Altitude
36,000 km
10,00015,000 km
7001,500 km
20 km
Number of satellites
34
620
40
Number of cells
800
~ 800
3,000
1/area
Signal delay
300 ms
~ 150 ms
50 ms
30 ms
Costs/coverage
Low
Medium
High
National
Subscriber capacity versus bandwidth
Low
Medium
Medium
Medium
Technologies 3.1.1
43
WPANs
WPANs provide communications in the closest environments (e.g., for indoor distances up to about 10m; for WLANs the distances are up to 100m). Thus, these networks preferably are used to connect a headset with a mobile device or to allow communication between a PDA and a desktop PC. A future step could be personalization, where devices in close proximity to a person would take notice of the person and start to interact in a personalized manner rather than in a general way. For example, a car would know individual personal adjustments (seat, temperature, music) depending on the key code of the driver; a TV set would know the users regular programs and viewing habits. 3.1.1.1 Bluetooth
Bluetooth [1] is a global computing and telecommunications industry specification for wireless short-range connectivity for mobile phones, computers, handheld computing devices, PDAs, headsets, other wearable devices, computer peripherals including printers, and human interface devices, such as datapads and mice. Using this technology, users of cellular phones, pagers, and PDAs will be able to buy a three-in-one phone that can double as a portable phone at home or in the office, quickly get synchronized with information in a desktop or notebook computer, initiate the sending or receiving of a fax, initiate a print-out, and, in general, have all mobile and fixed computer devices be coordinated. The technology requires that a low-cost transceiver chip be included in each device. Thirteen profiles currently exist for Bluetooth applications (as shown in Figure 3.2), and an additional 12 are under discussion. The 13 profiles are the generic access profile (GAP), service discovery profile, intercom, cordless telephony, serial port, headset, dial-up networking, fax, LAN access, generic object exchange, object push, file transfer, and synchronization. Additional profiles include PAN, local positioning, still image, AV, and video streaming. Each device is equipped with a microchip transceiver that transmits and receives data in the ISM frequency band of 2.4 to 2.4835 GHz that is available globally (with some variation of bandwidth in different countries). In addition to data, up to three voice channels are available. Each device will have a unique 48-bit address from the IEEE 802 standard. Connections are 1:1. The maximum range is 10m. The aggregate bit rate is 1 Mbps (later, up to 2 Mbps). The net bit rates depend on traffic characteristics, which are shown in Table 3.4. A frequency hop scheme (slotted TDMA) allows devices
44
Mobile sets
Video camera
Advanced hands-free
Stationary sets
Internet/ Intranet
GPS
Cellular network Pocket PC
Printer
PDA
Contactless electronic key Electronic payment
Figure 3.2 Bluetooth connectivity.
Desktop LAN equipment
Desktop
UMTS and Mobile Computing
Car
Technologies
45
to communicate even in areas with a great deal of electromagnetic interference. Built-in encryption and verification is provided to make sure that the right information arrives securely at the right partners. Bluetooths masterslave network configuration allows point-to-point communication, piconets (a cluster of eight devices), and scatternets (interconnected piconets, 10 clusters maximum). There is a lot of hype around Bluetooth, and many companies have introduced their first products. These companies are also working on implementations of the specification. Although the specification is good, it still takes some time until the mass market is reached. There are five primary criteria for the deployment of Bluetooth: 1. 2. 3. 4. 5.
Small implementation; Open specification; Low power; Low cost; Ad hoc connectivity.
There are some doubts as to whether the technology will be able to deliver its promises: Uncertainties exist with the propagation of 2,4002,500-MHz signals within confined areas and with the interference caused to the operating device in scenarios where WLANs coexist. Although the 2,400-MHz ISM frequency band is currently unlicensed, operators still need to apply for permission to operate services in some countries. It is unclear how long the band will remain unlicensed if the current rate of exploitation of this resource continues. From a networking point of view, there is great interest to integrate Bluetooth with WANs like UMTS and the Internet. There are still open questions on how to manage such a connection (e.g., as a simple point-topoint local call or as a subnetwork with always-on connectivity). (See the Bluetooth home page for more details [1].) The market expectations for Bluetooth are high. By 2005, a billion units should be brought to the market place. The basic problem of Bluetooth is interoperability. The Bluetooth Special Interest Group (BSIG) has resolved some of these problems, although there is still some work to do. For example, Bluetooth products need to be tested at a qualified test facility to ensure compliance with specifications. Testing of Bluetooth products is currently done against designated protocol test products called Blue Units. These can test a number of key functions, but their use is limited to partial testing of the baseband and link management functions. Coexistence with
46
UMTS and Mobile Computing
other radio interfaces integrated into the same device (e.g., GSM, GPRS, UMTS, IS-95) is of great importance. Bluetooth Basic Functions and Parameters
The main components of Bluetooth are as follows: • The radio transceiver with frequency hopping; • The baseband link control; • The link management software; • The antenna subsystem.
The transceiver is responsible for transmitting and receiving signals with the frequency hopping oscillator (1,600 hops per second) on a frequency modulated carrier. Spread spectrum schemes are used for point-to-point and -multipoint connections. For North America and most parts of Europe, it hops among 79 channels spaced 1 MHz apart, between 2.400 GHz and 2.4835 GHz (ISM band). In France and Spain, there is less spectrum available, and the system has only 24 channels. Bluetooth supports three transmit power classes: • Class 1 allows +20 dBm maximum output power with a maximum
distance of up to 100m (depending on the environment).
• Class 2 allows +4 dBm maximum output power with a maximum
distance of up to 10m.
• Class 3 allows 0 dBm maximum output power with a maximum dis-
tance of 1 to 2m.
Class 1 requires additional power amplifiers; the other classes are covered in the chip sets. The current specifications allow up to eight devices, which can automatically configure themselves into a piconet of one master and seven slaves. A slave can communicate with more than one master; this allows communication between several piconets. Synchronous traffic can be handled with 432.6 Kbps in either direction, and asynchronous traffic with 721 Kbps in one direction and 57.6 Kbps in the return direction. The key parameters of Bluetooth are shown in Table 3.4.
Technologies
47
Table 3.4 Bluetooth Specifications: Key Parameters Characteristic
Specification
Remarks
Carrier frequency (MHz)
2,400 2,483.5 (ISM band) 79 carriers
France: 2,446.52,483.5 MHz Japan: 2,4712,497 MHz Spain: 2,4452,475 MHz
Modulation
Gaussian-filtered binary frequency-shift keying at a line rate of 1 Mbps
Modulation index is 0.32, nominal; may range from 0.28 to 0.35 Peak deviation allowed is 175 kHz
Frequency hopping
1,600 hops per second in normal operation; four special hopping sequences for connection setup
Transmit power
Class 1: 1100 mW Class 2: 0.252.5 mW Class 3: 1 mW
Power control is required by power class 1; optional for other classes
Operating range (m)
0.110m
Up to 100m with power class 1
Maximum throughput
Asymmetric link with up to 721 Data throughput is lower than the Kbps in one direction and 57.6 1-Mbps line rate because of Kbps in the other protocol overhead Symmetric link with 432.6 Kbps in both directions
Bluetooth Products
A number of manufacturers are increasingly implementing the Bluetooth specification into such devices as notebooks, PCs, handhelds, PDAs, and mobile phones. The first Bluetooth headset was introduced by GN Netcom (GN9000) in 2001. It communicates with any standard phone as well as other Bluetooth-enabled devices. This includes Ericssons R250 mobile phone, one of the first mobile devices with Bluetooth connectivity. Bluetooth 2 in Development
Some companies (including Toshiba and others) are already working on Bluetooth version 2, which will have greater range (approximately 100m), more bandwidth, and more participants. Some companies of the BSIG want to increase the capabilities of Bluetooth so that it becomes more like a WLAN and maybe even someday replaces the WLAN in various scenarios.
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UMTS and Mobile Computing
BlueSky
BlueSky is a system for low-cost, low-power, indoor wireless networking for non-PC devices developed by IBM in 1998. At that time Bluetooth did not exist. When the BSIG was established, it was found that both systems shared the same goals. The development of the initial BlueSky project was then stopped because of the following inherent disadvantages in contrast to Bluetooth: • No peer-to-peer communication (needs an access point); • Module too big; • No IP network connectivity.
The next version of the BlueSky system will be built on top of Bluetooth. 3.1.1.2 HANs
The term home area network describes the one communication network at home that would interconnect all kinds of electronically controlled devices. Home Phoneline Network Alliances (HomePNA) are looking at ways to establish a network that covers the home as a whole. Likewise, a home radio frequency (HomeRF) system or a WLAN can accomplish the same. A variety of radio technologies are considered for home area applications; they are listed in Table 3.5. Possible HAN techniques are Ethernet, wireless Ethernet, WLAN, IEEE 1394, home audio-video interoperability (HAVi), and DECT. DECT is dominantly used in Europe, Asia, and South America for telephone and fax communications. One manufacturer in Germany is providing DECT modems for PC connections [3]. WPANs, Bluetooth, and infrared are appropriate for even smaller environments, basically for communication links between different personal user devices. A HAN, however, would tether those LANs. HANs connect computers, devices, and possibly a residential gateway. Figure 3.3 shows a HAN. Networking technologies are starting to invade the ordinary hometo carry, for example, telephone conversations; television, compact disc, digital versatile disk, MP3 music programs, and DVDs; signals from surveillance cameras; commands for controlling appliances; and multimedia flows from the Internet. With home networking, it is also possible for electric utilities to remotely control the flow of electricity into individual homes and to read their meters automatically.
Table 3.5 Wireless Home Radio Network Technologies
Application
Characteristics
Frequency Band (GHz)
Modulation
Bit Rate (Mbps)
Standardization Organization
802.11b FHSS
Wireless data networking
Encryption available
2.4
FH
0.53
IEEE
802.11b DSSS
Wireless data networking
2.4
Direct sequence
0.511
IEEE
Highspeed 802.11a
High-speed WLANs
Broadband multimedia 5 2.4
Discrete multitone/orthogonal FDM Spread spectrum
654 11
IEEE
HIPERLAN/2 Broadband radio access for IP networks (BRAIN)
High-speed multimedia LANs
Voice, data, video, can 5.45.7 coexist with 2.4-GHz systems, IP-based
Gaussian phase-shift keying
25
HIPERLAN Forum
Digital enhanced Voice and data for home Integrated voice and cordless data and offices telecommunications (DECT)
1.851.920 (country specific)
Gaussian frequency-shift keying
2
ITU/ETSI
UTRA-TDD
1.9/2
TD/CDMA
2
3GPP
Wireless communication High bit rate TDD for multimedia
Technologies
Radio System
Source: [2].
49
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UMTS and Mobile Computing
DECT 1.9 GHz PDA ISM band 900 MHz 2.4 GHz 5 Hz Embedded Web server
HAN
Home area network
Coax Phone Power RF
Ethernet /HAVi Phone line Power line (control and data) Wireless (home RF) Home-office WLAN
PAN
HPnP
Entertainment LAN IEEE 1394, HAVi
Figure 3.3 HANs. (Source: [4].)
At present, these networks fall into four major application areas: 1. Computer interconnection for accessing the Internet and connecting multiple PCs with peripherals for communications and entertainment; 2. Telephone and fax interconnections for internal and external communications; 3. TV and radio distribution lines; 4. Controlling items like lights, appliances, climate-control systems, and surveillance cameras. If the HAN is connected to the Internet, the user can do remote control via the Internet. This is known as the mini-Internet with embedded Web servers. The embedded Web server provides a user interface for accessing the control and supervisory functions for a home or a facility (for corporate applications).
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51
The physical basis of these networks is frequently voice-grade telephone wiring and coaxial cable, but electric power lines are also being used, as are wireless schemes, mainly in the ISM band. For HANs to succeed, home networks will have to be based on standard products operable with any of the media. These products include transceivers, network gateways, small servers, sensors, and controller-accepted OSs. For mass-market acceptance, networks will have to be inexpensive and easy to install, configure, and operate. Wireless home area technology is quickly developing for data and voice communications (see Table 3.5). In many situations it can provide a convenient and inexpensive networking solution in a home or small office. Since most homes with two or more personal computers were built before the recent explosion in telecommunications, they are not wired for a telephone in every room. Installing twisted wire-pairs all over the premises would be difficult. Power lines or telephone wires in the homes can also be used for all kinds of home networking: desktop PCs, printers, camcorders, cameras, and scanners all can be interconnected via ordinary copper telephone or power lines. Technologies support up to 25 nodes for distances across 20m and 1-Mbps bit rates over telephone wires are possible. A HomeRF system can either work as an ad hoc network of devices, which support only data communications, or as a managed network under control of a connection point. The HomeRF standard [5] is an open specification supported by more than 100 member companies to deliver a broad spectrum of affordable, interoperable consumer devices capable of both tollquality voice and high-speed data networking. Current supported applications include cordless voice telephony, in-home distribution and sharing of broadband data services, and file and print sharing. In 1999 seven leading companiesCayman Systems, Compaq, IBM, Intel, MobileStar Network, Motorola, and Proximhad HomeRF products. Planned HomeRF technology enhancements will support higher data rates, isochronous voice, audio, and streaming video communications, as well as broadband wireless Internet access outside the home. These enhancements will enable a whole new class of applications, including cordless telephony, streaming music and video, and broadband wireless Internet connectivity in public hot spots. HomeRFs operate in unlicensed frequency bands. They use the Shared Wireless Access Protocol (SWAP) to allow RF digital communications between PCs and consumer electronic (CE) devices for wireless voice and data communications anywhere in and around the home. This is actually an intermediate system between a WLAN and a WPAN like Bluetooth. SWAP
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UMTS and Mobile Computing
provides data communications and data sharing for up to 127 PCs, peripherals, cordless telephones, and other devices with a network stack. It also permits up to eight voice connections. It has up to 100 mW of power, which permits operation over a distance of up to 45m. SWAP uses the ISM band, which is available worldwide. It combines elements of the existing DECT and IEEE 802.11 standards. The protocol architecture closely resembles the IEEE 802.11 WLAN standards in the physical layer and extends the medium access control (MAC) layer with the addition of a subset of DECT standards to provide isochronous services, such as voice. As a result, the SWAP MAC layer can support both data-oriented services, such as Transmission Control Protocol/Internet Protocol (TCP/IP), and the DECT/GAP protocols for voice [6]. HomeRF products have already been released, including Intels AnyPoint products, PC cards, and PCI cards. Since Bluetooth is being introduced into such appliances, it is worth comparing SWAP HomeRF technology with Bluetooth (Table 3.6). 3.1.1.3 IEEE 802.15 Wireless Personal Area Network
In March 1999 the IEEE P802 LAN/MAN Standards Committee (LMSC) announced the formation of a new group called the P802.15 Working Group to develop standards for WPANs for portable and mobile computing devices. Portable and mobile computing devices are defined as unobtrusive computing devices, networking devices, software, and peripherals that are worn or carried by individuals to enhance their ability to perform productive work as well as to provide entertainment. The P802.15 Working Group works closely with special interest groups, such as Bluetooth and the Industry Consortia. The working group also solicits industry input, in general, on market requirements and technical solutions for a WPAN with 0 to 10m range, data rates of less than 1 Mbps, low power consumption, small size (less than 0.5 in3), and low cost relative to target device. The goal is to create standards that have broad market applicability and deal with the issues of coexistence and interoperability. The P802.15 products are optimized for the following: • Low cost relative to target device; 3
• Small size of approximately 0.5 in (excluding antenna and battery); • Power managementvery low current consumption (average 20 mW
or less at 10% transmit/receive load);
• Asynchronous or connectionless data links;
Technologies
53
Table 3.6 Comparison of HomeRF and Bluetooth HomeRF (SWAP 1.2)
Bluetooth
2.4-GHz frequency hopping
2.4-GHz frequency hopping
50 hops per second radio
1,600 hops per second
Optimized for voice and data in homes
Optimized for smart phones and computer devices
~ 1 Mbps
432.6 Kbps or 721/57.6 Kbps
Distance: 50m (house and yard)
Distance: 10m
8 near-line-quality voice links
3 near-line-quality voice links
Unlimited device links per base
7 device links per base
Peer-to-peer networking
Point-to-point and -multipoint connections
Native TCP/IP support
Point-to-point TCP/IP support
Low-power paging mode
Low-power standby mode
Lower transmit power possible
Higher transmit power possible
Based on 802.11 FH, OpenAir, and DECT
Based on TDD, packet transport
• The coexistence of multiple wireless PANs in the same area (20
within 400 ft2);
• Range of 0 to 10m; • Networking support for a minimum of 16 devices; • Bridge or gateway connectivity to other data networks; • Delivered data throughput of 19.2 to 100 Kbps (actual one device to
one device);
• Communicability between all devices within a WPAN; • QoS that supports a variety of traffic types. 3.1.1.4 DECT
The DECT system [7] is a local area wireless access system standardized by the ETSI for cordless communications in residential, corporate, and public environments, and providing for voice and data traffic. DECT is designed especially for a small area with a large number of users, such as in cities and corporate complexes. The system capacity depends on available frequency
54
UMTS and Mobile Computing
bandwidth; it has a technical limit of up to 100,000 users per km² of floor space in an office environment. The key features of DECT are designed to allow high capacity while maintaining high speech and data quality. Especially important is the unique DECT quick, seamless (no interruption), decentralized intercell or intracell handover, which elegantly copes with changing conditions, without need for central control. DECT is the most successful cordless standard worldwide. It is a family member of the ITU IMT-2000 radio standards. There are more than 100 million DECT systems in the marketplaces in Europe, Asia, Africa, and North and South America. Figure 3.4 shows DECTs technical characteristics and the layer structure. The Concept of the Basic DECT Base Station
The basic DECT base station consists of one single radio transceiver that can change frequency from slot to slot. This comes from the systems flexibility, where the base station can on each time frame operate on all twelve duplex time slots, each slot operating independently on any of the 10 DECT carriers. While operating on different carriers, each call connected to the same base station always uses a different time slot.
C-Plane
U-plane
Signaling Interworking application process
Application processes
Management entity
DECT technical characteristics RF channels
Data rate
Network layer Data-link control layer
Data-link control layer
Medium-access control layer Physical layer DECT layer structure
Transmit power
MC TDMA/TDD (multiple channel time division multiple access/ time division duplex*); max. 10 carriers, 1.782 MHz carrier spacing/12 duplex TDMA slots per carrier 1152 kbps Frame length 10 ms 24 × 0.417 msec traffic slots (twelve for each direction) Transmission burst 361 ms with 56 ms guard space 250 mW peak/10 mW average
Speech encoding 32 kbps (half-rate 16 kbps), G.721ADPCM Modulation GMSK (BT = 0.5) (Gaussian minimum shift keying) Equalization None (but will use spacial diversity) *This is referred to as TDMA/FDMA/TDD
Figure 3.4 DECT.
Technologies
55
With a complexity comparable to that of a DECT handset, the base station has a capacity corresponding to 12 radios and a combiner in traditional analog land mobile radio systems. It offers a high grade of service with high traffic capacity. Dynamic Channel Selection
DECT utilizes a simple but efficient and robust dynamic channel selection (DCS) procedure. DECT physical channels are allocated decentralized between each portable device and its closest base station. For each call, the portable device chooses a channel that for the time being is best for the wanted local connection. The most basic advantage of this is that different systems, systems operators, and types of services can, in a self-organizing way, utilize the same lump of available channels without prior distribution of channels to specific services or base stations. Mobile radio systems with in-principle fixed channel allocationlike NMT, TACS, AMPS, and GSMdo not provide this important feature. In addition, these systems need to be planned to a worst-case situation, while DCS takes the actual interference situation into account. Furthermore, driven by customer needs, each service or equipment provider can increase its own capacity by increasing its base station density. As a consequence of the DCS procedure, there is no need to plan in detail how many channels are needed per base station. This maintains a high grade of service even with local density variations. Call Setup Using Base Station Beacon Channels
Each base station is always active on at least one channel, and every active channel broadcasts system information and base station identification. This allows any portable (by receiving only) to identify any system or base station within reach. When a handset has recognized a desired system simply by listening, the receiver locks to it by locking on any active channel on the strongest (nearest) base station. In this idle locked state, the handset listens every 160 ms for a possible paging call from the system. When the handset wants to contact the system, either because it wants to originate a call or because it has been requested to do so by a paging call from the network, the DCS procedure looks for a free physical channel and accesses the system by sending an appropriate burst. Setting up calls (or handing them over) to the closest (strongest) base station provides stable DCS, high capacity, and high link quality.
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UMTS and Mobile Computing
Handover
In order to accommodate very small cells, the need arises for quick and seamless handover, requiring neither central control nor complicated procedures. The key to seamless handover is TDMA in combination with decentralized DCS. The old link is maintained on one slot in the portable device, while the new link is set up in parallel on another time slot. When the new link is established, the (new) base station requests the central to make a seamless switch from the old to the new radio link. The handover is device-controlled: while it communicates on the original link, it scans the other channels and records free channels and the identities of base stations that are stronger than the current one, and is thus prepared to perform a quick handover. Handover is made as soon as another base station is stronger than the one of the current connection. Thus, in a well-engineered system it is always performed before the quality decreases. The nature of DCS is that a channel in use can occasionally get stolen, and therefore the quick DECT seamless intercell and intracell handover increases the capacity and cuts call curtailments drastically. DECT does not depend at all on the old channel to quickly set up the new one. In a simple DECT application, the DECT base station is hooked up to the outlet of the public telephone system (the PSTN), as shown in Figure 3.4. The base station operates on 10 carrier frequencies simultaneously, and each carrier frequency provides for 12 duplex channels. Thus, a single base station can support theoretically up to 120 mobile units at the same time. The average transmission power of 10 mW (peak power of 250 mW) provides for indoor mobility typically up to 50m and 300m outside of buildings. Despite this low power, DECT offers ISDN speech quality, which clearly outperforms analog systems and even other cellular phone systems, such as GSM. From an addressing point of view, DECT follows the ITU E.164 subnetwork addressing scheme and can be fully integrated into private branch networks. Personal Handyphone System
PHS is similar to DECT, but exists only in Japan and in a few other countries. It has 20 million devices in Japan that provide for both voice and data. 3.1.2
WLANs
A LAN is a network of interconnected workstations sharing the resources of a single processor or server within a relatively small geographic area. Typically,
Technologies
57
this might be within the area of a small office building or campus. Usually, the server has applications and data storage that are shared in common by multiple workstation users. With a WLAN, a mobile user can connect to a server through a radio connection. Wireless technologies for LAN connections include frequency hopping, spread spectrum, microwave, and infrared light. Several companies developed the first WLAN products about a decade ago. Early WLAN systems were expensive, and their data rates were too low. They were prone to signal interference and consumed power of far in excess of 100 mW for bit rates from 200 Kbps up to 1 Mbps. The interoperability problem between systems of different manufacturers was another reason why this standard did not reach market success until recently. The systems work like the more advanced standardization products in the unlicensed frequency band in the 2.4-GHz range. In mid-1990 IEEE formed the P802.11 Working Group with the aim to develop a common standard. This standard was completed by 1997 and comprised three physical layer solutions: two radio-based solutions (frequency hopping and direct sequence) and one infrared. The MAC layer is common regardless of the physical layer used. 3.1.2.1 IEEE 802.11 Wireless Local Area Network Standard (802.11a and 802.11b)
The client-server network uses an access point that controls the allocation of transmit time for all stations and allows mobile stations limited roaming from cell to cell within the same WLAN environment. Roaming between different WLANs may cause interoperability problems and is dependent on the backbone network. The access point is used to handle traffic from the mobile radio access system to the wired or wireless backbone of the client-server network. This arrangement allows for point coordination of all the stations in the basic service area and ensures proper handling of the data traffic. The access point routes data between the stations and other wireless stations or to and from the network server. Typically, WLANs are controlled by a central access point called an access controller or gateway, which includes functions for IP access control. WLANs are used mainly in the corporate sector, but also in small office environments and in homes. WLAN cards with a size of 176 × 54 × 5/10 mm (PC card extended type II) give laptop and desktop users wireless data access up to theoretically 11 Mbps. The cards also are compatible with a wide range of pocket computers and handheld devices (PDAs) equipped with a type II or type III PC card slot. They support peer-to-peer or ad hoc networking to wired Ethernet networks via access points. The WLAN access
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UMTS and Mobile Computing
controller, sometimes referred to as a wireless bridge, provides the radio coverage with theoretical cell radii from 20 to 100m indoors and, depending on the product, up to 300m outdoors. Point-to-point connections with directional antennas allow larger distances of up to 2 to 3 km. Practical cell radii vary depending on the product. Benchmark tests [8] have shown that IEEE 802.11 frequency hopping spread spectrum (FHSS) techniques reach their limits at 3 Mbps, while the direct sequence spread spectrum (DSSS) techniques may achieve higher bit rates up to 11 Mbps depending on transmit power, cell size, number of simultaneous users, application, and cellular environment. Twelve products from different manufacturers were benchmarked with file transfer of 64-MB date files and TCP/IP traffic with 4-KB block size. The throughput results varied depending on the terminal distance (d ) to the access point (Table 3.7). Typically, user environments are offices, business parks, and various campus areas, corporate buildings, railway stations, airport lounges, and hotels. Some manufacturers also provide solutions that can be integrated into a public WAN [e.g., by using the subscriber identity module (SIM) card for GSM access, the WLAN terminal will get the SIM inserted and have access software to communicate with GSM]. The WLAN is connected to the GSM network by a server, which takes over authentication and mobility management. For 3G networks like UMTS, such functionality is presently under research in the Broadband Radio Access for IP-Based Networks (BRAIN) program (see Section 3.1.2.2). Table 3.7 Ranges and Bit Rates of IEEE 802.11b WLANsMeasurements and Specific Targets Maximum Bit Rates Indoor Office
Semiopen Office
Measured Values*
On-sight Office
Specified Target Values
Distance from access point
d = 2.5m
21m
45m
60m
100m
300m
Max. bit rate for FTP (Mbps)
2.66
1.34.8
0.55
11
2
1
Max. bit rate for TCP/IP (Mbps)
2.76.1
2.55
0.55
11
2
1
*(e.g., 2.66 depending on the product)
Technologies
59
IEEE 802.11a
This standard specifies a different physical layer 1 than 802.11 (and 802.11b) by using orthogonal frequency division multiple access (OFDMA). The target is to achieve 54-Mbps bit rates. The IEEE 802.11a specification amendment from 1999 defines the physical and the MAC layer. 802.11a products are foreseen to operate in the United States from 5.8 to 5.9 GHz and, according to the ITU WRC 2000 resolution 736, also in the 5.475.725-GHz and 5.155.35-GHz range. IEEE 802.11b
Products based on this specification also work in the ISM band. Their physical layer uses DSSS, whereby interference is reduced, thus higher spectral efficiency and low power consumption is achieved in contrast to IEEE 802.11. In contrast to FHSS, which has a smaller carrier bandwidth (1 MHz) compared to DSSS (11 MHz), it provides higher transmission bit rates and distance. DSSS, however, offers fewer potential channels and less scalability. IEEE 802.11b products are available in all parts of the world and have the following technical properties: • Up to 14 channels; • Frequency range ISM band; • 5-MHz carrier channel spacing in European Conference of Postal • • • • • • • • • • •
and Telecommunications Administrations (CEPT) countries; Direct sequence spread spectrum modulation technique (11 chips code); PCMCIA type II interface; Media Access Protocol CSMA/CD with ACK; Card dimensions: 118180 × 54 × 512 mm; Frame error rate < 8%; Peer-to-peer or point-to-multipoint communication; Power consumption; Transmission approximately 300 mA; Output power up to approximately 30 or 40 mW; Ranges (theoretical values) up to 200m; Bit rates up to 11 Mbps.
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UMTS and Mobile Computing
WLANs are completely protocol transparent like Ethernet or Token Ring LANs. Interoperability problems usually come from the higher bit error rates and propagation delay times of the WLAN. The WLAN MAC works similar to that of the Ethernet IEEE 802.3. Two methods for access exist: 1. The centralized approach, called point coordination function (PCF); 2. The decentralized approach, called distribution coordination function (DCF). The Ethernet basic access method is used in the DCF mode: it is called carrier sense multiple access/collision avoidance (CSMA/CA). Collision detection (CD) is not used because it cannot be distinguished from other radio-related distortions. Instead, the WLAN uses collision avoidance (CA). IEEE 802.11b WLAN can be interfaced with IEEE 802.3 or 802.5 wired LANs, depending on the manufacturers product compliance with the standard. HIPERLANs
In 1996 the European Radio Committee (ERC) decided with ERC/DEC/(96)03 to dispute the frequency band 5.15 to 5.25 GHz for HIPERLANs conforming to ETSI standards. Furthermore, it was agreed that the band 5.25 to 5.35 GHz was to be designated for use on a regional and national basis. Regarding the frequency bands in the ITU Region 1 CEPT [Europe and the Commonwealth of Independant States (CIS; the former Soviet Union)], the following was decided: • To use 5.15 to 5.35 GHz for HIPERLANs (HIPERLAN/2) in-
doors, with a maximum output power of 200 mW;
• To use 5.47 to 5.725 GHz for HIPERLANs indoors and outdoors,
with a maximum output power of 1W.
HIPERLANs were specified within the framework program called BRAN. HIPERLAN/1 provides bit rates up to 23.5 Mbps and is compatible with Ethernet and Token Ring LAN standards according to ISO 8802.3 and 8802.5. User mobility is restricted within the local service area only. The technical specification was released by ETSI in 1997.
Technologies
61
HIPERLAN/2 provides up to 25 Mbps and is foreseen to be linked with IP networks. The typical operating environment is indoors. Restricted user mobility lies within the local service area. Linking with WANs is on a proprietary basis. The modulation scheme is different from HIPERLAN/1. HIPERACCESS (also known as HIPERLAN/3) and HIPERLINK were studied for the purpose of multimedia use with high bit rates up to 155 Mbps in higher frequency ranges (e.g., 17 GHz). 3.1.2.2 HIPERLAN/2 and BRAIN
HIPERLAN/2 is a WLAN based on ETSI standards. BRAIN [9] is a research project under the Information Society Technology (IST) program of the European Union working to define an open architecture for integrated mobile radio access networks with IP-based core networks (e.g., UMTS and Internet). Roaming is a key issue including a handover algorithm between different types of radio networks. WLAN systems complement wide area cellular networks in specific environments, and indoors, they provide higher bit rates with high-capacity hot-spot coverage. They are complementary also regarding the frequency bands. The regulatory issues regarding roaming between license-exempt networks and licensed public operator networks (coexistence of radio networks with different owners) are not yet clarified on a global basis. The main issues in the development of BRAIN specifications are as follows: • To define quality of service types for transport over the radio link; • To specify an efficient IP transport over the radio link; • To define mobility and handover mechanisms between WLAN and
UMTS;
• To define service-oriented IP layer for convergence.
The BRAIN radio interface is HIPERLAN/2, which defines the physical and data link control layer with error control, the MAC layer (see Table 3.8). The convergence layer enables interconnection with different link layers, such as Ethernet and FireWire. Also, the Internet IPv4 and IPv6 specifications have to be supported. ETSI and the HIPERLAN/2 Global Forum (H2GF) signed a cooperation agreement in 2001 to ensure future standardization in this sector (ETSI project EPBRAN).
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UMTS and Mobile Computing Table 3.8 BRAIN Layer Based on HIPERLAN/2 BRAIN Layers
HIPERLAN/2 Specifications
Layer 3
Service-specific convergence layer (IP) Common convergence layer Radio link control Error control
Layer 2
MAC
Layer 1
Physical layer
3.1.2.3 WLAN Deployment and Products
WLAN deployments are beginning to appear with the simplest configuration of a point-to-point interconnection between two computers. Two computer WLAN cards allow spontaneous connectivity without accessing the Internet or an intranet. Of course, drivers need to be installed, the configuration of the client and server-software needs to be set up, and the communication needs to be initialized and executed. Each host has its own radio cell as long as the peer-to-peer communication can take place. In case of a multihost configuration, a hub has to be put in place (the star configuration according to IEEE 802.3). Such a configuration has the status of an ad hoc network, again without connection to the Internet or an intranet. If needed, however, a configuration with the setup of an access point allows the interconnection with an existing wireline Internet or intranet. The logical function of the access point is called a bridge to a LAN or Internet environment. The communication between clients and server remains completely transparent. The access point also allows an extension of the WLAN via twisted pairs to extend the distance between WLANs. WLAN products include the following: • Aironets [10] IEEE 802.11 compliant in-building WLAN product
lines include several types of products like access points and WLAN adapters. They are available with 900-MHz or 2.4-GHz DS radios or 2.4-GHz FH radios.
• Lucent Technologies Orinoco [11] is conforming to the IEEE
802.11b standard. It provides Ethernet quality performance to
Technologies
•
• •
• • • •
63
mobile workers within an enterprise and is backward compatible with the earlier 10Base2 coax network systems. Proxim [12] offers RangeLAN2 as a multistandard WLAN. Their MobileStar system provides T1 connectivity to the Internet using RangeLAN2. RangeLAN2 is based on the OpenAir standard and is interoperable with over 40 different devices. The Symphony Cordless Networking Suite is a cordless 1.6-Mbps Ethernet LAN with a 150-ft range through walls and floors using 2.4-GHz spread spectrum technology. RangeLAN802 is Proxims IEEE 802.11 product line. It has the interoperability certification from the Wireless LAN Interoperability Forum (WLIF). Intermec [13] also offers WLAN products that are compliant to OpenAir and IEEE 802.11. Nokia Networks [14] offers WLAN products, P022 access controllers, and C110/111 WLAN cards that are based on IEEE 802.11b with connectivity to GSM and partial roaming capabilities (SIM cardbased). Siemens IGate is compliant with IEEE 802.11b. It is designed similar to an access router solution with a wireless interface. Symbol WLANs [15] WLAN technology is based on IEEE 802.11. WebGear [16] designs wireless local area networking for business and home applications. Z-Com Wireless Networking Company [17] offers IEEE 802.11 WLAN compliant products.
Other manufacturers include BreezeCOM, Diamond Home Free, NDC Instant Wave, Nortel Bay Stack, and RadioLAN. 3.1.3
Wireless WANs
WANs are generally understood as being nationwide or regional networks using medium- and long-range radio technologies. Cellular arrangements are required in order to achieve the expected radio coverage with acceptable amount of spectrum. Radio access techniques may varythey are often understood as technologies in the scope of 1G, 2G, and 3G systems (see Figure 3.5). First-generation systems use analog radio access techniques based on frequency division multiple access (FDMA). For mainly the same applications, 2G systems use digital radio techniques, such as TDMA and CDMA.
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UMTS and Mobile Computing
Migration
Migration
1G
2G
3G
Future evolution
Analog speech
Digital speech + low-rate data up to < 50 kbps
Very high bit-rate software radio
NMT, AMPS, TACS
GSM, PDC, IS-95 IS-136 (D-AMPS)
Multimedia services (≤ 2 Mbps) 2+G services IMT-2000, UMTS, CDMA 2000, UWC136
1980
1990
2000
2010
Figure 3.5 Wireless WANs. (Source: Siemens.)
Third-generation systems involve multimedia applications which require wideband systems; thus, CDMA, which uses wideband frequency carriers, is the dominating technique, partly combined with TDMA. 3.1.3.1 Radio Access Techniques
Cellular mobile communication systems, cellular telephone systems, and wireless communication systems all use radio-wave analog or digital transmission in which a subscriber has a wireless connection from a mobile device or telephone to a relatively nearby transmitter. The transmitters span of coverage is called a cell. Generally, cellular mobile communication service is available in urban areas and along major highways. As the user moves from one cell or area of coverage to another, the device is effectively passed on to the closest available cell transmitter. Second-generation cellular mobile communication systems today offer data speeds typically up to 20 to 50 Kbps, and service is paid depending on the duration of the call or data packets. A cordless telephone is simply a phone with a very short wireless connection to a local wireline networkDECT is one example. A personal communications service (PCS) may comprise both. Wireless communications systems use several different access techniques, usually referred to as air interfaces. The principal common access techniques include the following: • FDMA; • TDMA;
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• CDMA; • Combinations of TDMA and CDMA or TDMA and CDMA with
smart-antenna techniques (TD/SCDMA).
FDMAoften referred to AMPS, NMT, or TACSuses narrowband channels of spectrum, each carrying one telephone circuit, in a system where any mobile can access any one of the frequency channels. Existing analog cellular systems use FDMA. (See Figure 3.6.) TDMA divides each carrier frequency into a number of time slots, each of which constitutes an independent telephone or data circuit. Each call is assigned a time slot. The Telecommunications Industry Association (TIA), which is today named the Cellular Telecommunications Industry Association (CTIA), endorsed TDMA in 1990, and some North American digital cellular and PCS systems use TDMA. Additional TDMA standards are the PDC System developed in Japan and the GSM. Endorsed by ETSI in 1990,
e Tim
Signal power
Channel allocation via frequency carriers: FDMA
Carrier
f1
f2
f3
f4
fx
Channel allocation via time slots: TDMA Frequency
e
CDMA
Tim
Signal power
Channel allocation via spreading code
Carrier bandwidth f = (f1 + f2 + f3 + … + fx + …) Figure 3.6 TDMA, FDMA, and CDMA.
Frequency
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GSM uses TDMA with frequency hopping in that it divides each carrier frequency into a number of time slots; in addition, other frequency carriers are used for frequency hopping. GSM is the primary standard for wireless communications systems, and there are nearly 500 GSM networks worldwide [18]. CDMA is a form of spread spectrum packet-based wireless transmission technique. Instead of using frequencies or time slots, it uses mathematical codes and spread spectrum technology to transmit and distinguish between multiple wireless conversations. Its bandwidth is much wider than that required for simple point-to-point communications because it spreads the information contained in a signal of interest over a much greater bandwidth. Where FDMA techniques transmit one connection per carrier and TDMA techniques are limited to a definite number, CDMA techniques have no hard limit to transmitting a high number of channels. All these access techniques have their advantages and disadvantages, which are taken into account when selecting between air interface proposals. Theoretical investigations, computer simulations, and available technologies also contribute to this process. Theoretically, all the access techniques are comparable. The theory is laid down in the Shannon formula, which defines the channel capacity as a function of the used bandwidth and the signal-tonoise ratio related to Gaussian noise conditions: C = B log2 (1 + S/N ) where C = the channel capacity in bits per second, B = frequency bandwidth in hertz, and S/N = signal-to-noise ratio. The Shannon formula says that a given capacity can be obtained as follows: • By assigning the channel to a narrow band and pursuing at the
same time a high value of S/Nthis is typically the case in FDMA/TDMA systems;
• By using a much wider band (factor 10 to 30), admitting for lower
values of S/N. This case arises in CDMA where all users are transmitting and receiving on the same frequency band and each connection perceives a signal like noise. The discrimination between different user information is performed by assigning different codes to the users.
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The same code is used for subsequent information during a connection, for encoding on the transmit side and for decoding on the receive side. All the schemes can be used also in combination (e.g., TDMA/ CDMA). The most promising solution for 3G systems that allow wide frequency band transmitters is to use direct sequence CDMA for the so-called frequency division duplex (FDD) mode: one wideband frequency carrier is used in either direction. For duplex traffic it makes use of paired frequency bands (uplink/downlink). In addition, in case of allocation of unpaired frequency bands, the so-called TDD mode is used: time division duplex combined with CDMA. Forward and backward direction of traffic flow is handled via time slot assignments within the same band; the signals are encoded and spread over the entire frequency band. An additional function is introduced in CDMA technologies: the reuse of the same frequency carrier in the neighbor cells; connection hand-off is handled by codes. This mechanism guarantees the connection continuity (while the mobile terminal is crossing cell borders) by doubling the active channels between the mobile terminal and an equivalent bridging point in the network. This double path is maintained along the connection, so that the continuity is ensured through an asynchronous acquisition-release process, which relaxes the stringent time constraints characterizing the hand-over execution in the present systems. The acquisition and release process that takes place along a connection is driven by the signal level received by the mobile terminal in its actual position. This is called macrodiversity, which provides great advantages in terms of quality of service, but it induces a significant complexity on the access network and in the terminal. In fact, the network must identify the combining and multicasting point that recovers, in the upper direction, a single path from the multiplicity of equivalent paths in progress in the radio interface (combining) and create, in the downward direction, the necessary equivalent paths to be directed towards the mobile terminal. This point changes dynamically with terminal movement and may be allocated at different hierarchical levels, depending on the network topology. 3.1.3.2 From 1G to 2G and 3G Systems
There are some 1G systems still in the marketplace. All systems use FDMA radio access techniques. The most prominent system is the Analog Mobile Phone System (AMPS), which was developed in the United States in the 800-MHz bands. In the 1990s, it reached worldwide distribution, as a de facto standard. Worldwide roaming was not really possible due to some restrictions on internetwork signaling and authentication. There are other
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1G systems like NMT, TACS, and C-Net developed in Europe. They also gained market acceptance beyond the European region. Of these, AMPS (also known as the IS-54 EIA/TIA standard) was the only system that was upgraded with second-generation radio access techniques (digital AMPS, DAMPS). It continued on the core network (IS-41 standard) side with some past restrictionsfor example, limitations for international roaming and numbering, end-user security items, and international charging conventions. AMPS and DAMPS are still the most widely deployed cellular systems in the United States and Canada, as well as in Latin America. In the United States, these systems provide 98% coverage. DAMPS represents the evolution of AMPS to digital radio access. DAMPS is also known as the IS-136 radio standard. Second-generation systems introduced digital technology into the radio transmission. They use different radio access techniques. The most prominent systems are described as follows. Cellular Digital Packet Data
The Cellular Digital Packet Data (CDPD) system is an overlay on existing AMPS and DAMPS cellular voice systems that supports packet data transmission over the same frequencies. Modular and flexible, the CDPD system can be integrated with existing AMPS/DAMPS systems from other suppliers. It can also coexist with 2G TDMA and CDMA technologies. The system complies with the specifications set forth by the CDPD Forum, a consortium of leading companies in the wireless communications and computer industries. Subscribers to CDPD services benefit from such advantages as computer-aided dispatch, immediate status information on field technicians, higher productivity per worker, better response time to customers, immediate access to current and accurate computer-based information, and rapid responses to emergencies. Data transmission takes place during idle times on voice channels without adversely affecting voice quality. For AMPS networks, this is accomplished by detecting idle voice channels (sniffing) and switching to them to transmit and receive data. CDPD operates at 19.2 Kbps with an actual throughput between 8 and 11 Kbps. On TDMA and CDMA, it uses dedicated frequencies. Packet signals from multiple users are combined over the same channel, which provides far more revenue per channel than circuitswitched data solutions. Conformance to industry-standard protocols, such as OSI/CLNP, makes CDPD compatible with major public and private packet-switching
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networks. The use of an open systems architecture provides flexibility and expansion beyond that of existing controller or router-based systems. CDPD radios use existing Series II equipment for data transmission, eliminating the need for separate T1/E1 links, antennas, and amplifiers. You can mix voice, data, and digital technologies on the Series II wideband amplifier. The result is lower equipment costs with uncompromised voice service and superior data communications performance, without reengineering cell sites. TDMA
TDMA is a technology used in digital cellular mobile communications. Each frequency channel is divided into time slots in order to increase the amount of data that can be carried over one carrier. TDMA is used by D-AMPS, GSM, and PDC. Each of these systems, however, implements TDMA in a somewhat different and incompatible way. An alternative multiplexing scheme to FDMA with TDMA is CDMA, which takes the entire allocated frequency range for a given service and multiplexes information for all users across the spectrum range at the same time. The TDMA scheme was first specified in the GSM standard in 1987, then in the Electronics Industry Association/Telecommunication Industry Association (EIA/TIA) Interim Standard 54 (IS-54). IS-136 is the evolved IS-54 standard and is used today in the United States together with GSM, the 2G TDMA standard. It is operating in the 800900-MHz band and, like GSM, also in the PCS 1.9-GHz band. AT&T is the largest IS-136 operator with 15 million users in 2001. It simultaneously offers a GSM1900 service. Other operators follow, with a combined subscription of approximately 12 million users in 2001. The Universal Wireless Communication Consortium (UWCC), a group of leading IS-136 operators and manufacturers (launched in 1995), promoted TDMA/IS-136-based technology innovations and standards. In 2002, key players in the United States created a new trade organization to promote the evolution from IS-136 to EDGE and UMTS. The digital cellular service IS-136/D-AMPS has added to FDMA an additional subdivision of each channel using TDMA to get three channels for each AMPS channel, tripling the number of calls that can be handled on a channel. The beginning of the EIA/TIA standard goes back to 1988. The CTIA published a set of user performance requirements on the existing AMPS standard, with the inclusion that a new digital system would be compatible to the analog technology. The frequency band was the same as for AMPS: from 824 to 849 MHz for mobile station transmit and 869 to 894 MHz for base
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station transmit with the same channel spacing parameters. The first issue of air interface specifications was approved as IS-54 (dual mode) standard by 1991. In 1994 an enhanced specification was released, designated IS-136; its main feature was the addition of a digital control channel. New services like SMS, data, and fax were introduced later in these networks. The way of the standard goes clearly in the same direction as GSM, with EDGE/GPRS and UMTS. The TDMA developments in Japan took place in the early 1990s and specified the Personal Digital Cellular (PDC) System, which operates in the 800-MHz (843940 MHz) and 1.5-GHz (14291453 and 14771501 MHz) band. The standard is quite similar to GSM and later also included a packet service with 9.6 Kbps, which was used to introduce the mobile Internet i-mode offerings. The PDC evolution continues with IMT-2000/ UMTS, where Japanese industries are contributing actively. CDMA
CDMA is based on spread spectrum transmission, which allows multiple users to share the same radio frequency spectrum simultaneously by assigning each active user a unique code. Code can be conceptualized as a scrambling algorithm that randomizes the transmission so it appears as a noise to all receivers except the intended receiver. As a part of call setup (when the sending begins), the recipient is told the specific code used for that call and then unscrambles the desired signal (while all other signals appear as noise). This technique allows numerous voice or data calls to be simultaneously transmitted on one radio frequency carrier. To operate successfully, all accessing signals must be received at a similar level. Thus, power control is essential to the successful operation of individual terminals while roaming. The different codes for the mobiles also allow them to reuse the same frequency carrier in adjacent cells to be switched over via soft hand-off, since a terminal may be served by several base stations at any one moment. This technique allows an increase in network capacity. The first CDMA mobile cellular systems were built in the United States and in South Korea. The standard was called IS-95. Later innovations were released after 2000: cdma2000, a trademark of TIA, provides data services in a number of steps. The data rates shown in Table 3.9 are theoretical values; the practical values are lower (e.g., 1 RTT in Korea has 70 to 90 Kbps). Verizon Wireless in the United States is probably the largest IS-95/cdma2000 operator worldwide with 20 million IS-95 voice users and approximately 1 million data users in 2001. The second largest is SK
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Table 3.9 CDMA Development Year
Standard
Bit Rate
Carrier Rate
Developed by
1996
IS-95A
9.6/14.4 Kbps
1.25 MHz
USA
1999
IS-95B
64 Kbps
1.25 MHz
Korea/Japan
2001
1 RTT (IS-95C)
144 Kbps
1.25 MHz
Korea
2002
1 EV-DO
2 Mbps (theoretical)
1.25 MHz (data only)
USA
2003+
1 EV-DV
2 Mbps (theoretical)
1.25 MHz (data and voice)
USA
3 × RTT
2 Mbps (theoretical)
5 MHz
USA
Telekom in South Korea with 11 million users in 2001. These operators have taken up data services on the basis of 1 × RTT. IS-95 innovations are also known as narrowband CDMA because its carrier bandwidth is 1.25 MHz in contrast to the 5-MHz bandwidth of the so-called wideband CDMA (WCDMA), which is part of the UMTS radio standard. Narrowband CDMA performance depends on multipath channels. CDMA typically provides better capacity in long delay spread channels. Downlink fast power control improves CDMA capacity performance in short delay channels but reduces capacity in long delay spread channels. A growing number of industry observers, however, point out that WCDMA brings higher data speeds; thus, fewer 3G service licensees will take the CDMA 2000 route. The WCDMA development took place in Japan and in Europe. In Japan, Nippon Telephone and Telegraph (NTT) DoCoMo started research work in the early 1990s, and in Europe development began in 1995 under the research program of the European Commission (EC) called advanced communications technologies and services (ACTS) and future radio multiple access schemes (FRAMES). The future radio multiple access scheme (FRAMES) project was the terrestrial radio interface research project dealing with wide area broadband transmission up to 2 Mbps and higher. This project also undertook studies on combined TDMA-CDMA principles and investigated the basic architecture for the wideband CDMA standard. Both
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were accepted by ETSI in 1998 as a proposal for a global 3G standard to the ITU [18]. This standard was also supported by the Japanese standardization organization, the Association of Radio Industry and Business (ARIB), and by Telecommunications Technology Committee (TTC) Korea. It comprises two operational modes: FDD, which is WCDMA, and TDD, which is TD-SDCMA/low chip rate (LCR) or TD-CDMA/high chip rate (HCR). GSM
GSM is not just a radio standard, it specifies a complete digital cellular network from the mobile terminal to the radio and switching part. Approximately 500 GSM networks are operating in 170 countries worldwide. It provides almost complete coverage in Western Europe, and growing coverage in the Americas, Asia-Pacific, and Africa [18]. In 1987 the European Union issued a directive to all member states to clear until 1991 the same frequency bands from 890 to 915 MHz for mobile transmission and from 935 to 950 MHz for base station transmission. Several air interface candidates were put forward with the final decision in March 1987 to adopt the TDMA narrowband proposal. This proposal is based on a 200-kHz carrier bandwidth, each with eight time slots. Power control technique and frequency hopping are used to increase system capacity by reducing average interference levels. Benefits of GSM Because GSM is the most commonly used 2G protocol, serving more than 600 million subscribers by the end of 2001, and because WCDMA/EDGE is emerging as the accepted 3G technology, this evolutionary pathway offers clear advantages in the depth and quality of its terminal, infrastructure, and application portfolios. The economies of scale associated with this global standard ensure good selections and competitive prices for these products. Standardization ETSI has established comprehensive standards for GSM technology, ensuring the interoperability of terminals and infrastructure. Similarly, the Third Generation Partnership Project (3GPP) has served in this same role during standardization activities aimed at UMTS, working to ensure that global roaming and interoperability can be provided through a highly standardized 3G framework. These standards allow operators to select base stations and other equipment offered by a number of competing vendors. An open, standardized technology also ensures more reliable roaming performance and the smooth compatibility of elements across networks and geographic regions.
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GSM is the incubating technology for many of todays most popular value-added wireless services. In fact, features like SMS, the circuit and packet data services, and the location-based services are deployed by taking advantage of a wide user reachability. Notable features available via GSM include the following: • SMS chat, picture messaging, ring tones, logos and icons, •
• •
• • • • •
datagram-switched via control channels; Circuit-switched data at 9.6 to 14.4 Kbps to high-speed circuitswitched data (HSCSD) at n × 14.4 Kbps (e.g., 2 time slots = 28 Kbps; 3 time slots = 43 Kbps); WAP, circuit-switched and packet-switched via GPRS; Packet data: GPRS with bit rates of 20 to 40 Kbps; enhanced GPRS with bit rates of 50 to 120 Kbps depending on the number of assigned timeslots; Location-based services (Cell ID, EOTD, TDOA, and GPS); Accessories (handspring visor GSM module, telematics, and more); SIM card (security, m-commerce, SIM Toolkit, class 2 SMS handset configuration control, prepaid card, and future micropayment); GSM Supplementary Services (voice mail, SMS, e-mail conversion, unified messaging); Integration with enhanced message service and instant messaging on the Internet.
The unique global roaming features of GSM allow cellular subscribers to use their services in any GSM service area in the world in which the home operator has a roaming agreement. That means the phone you use in France could work in Germany, Australia, Finland, New Zealand, North and South America, Africa, and even in China, depending on your providers roaming agreements. GSM-enabled phones have a smart card inside called the SIM. The SIM card is personalized. It identifies the personal account to the network and provides authentication, which allows appropriate billing and personalized services. GSM is the most widely used of the three digital wireless telephone technologies (IS-136, GSM, and CDMA) and uses TDMA in different modes: circuit-switched time slots (single slot for voice and data up to 14.4 Kbps, multiple slots up to 8 × 9.6 Kbps) and packet switched (up to more than 100 Kbps, also with higher modulation schemes). GSM digitizes
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and compresses data, then sends it down a channel with other streams of user data, each in its own time slot or in combined time slots. It operates at either the 900-MHz or the 1,8001,900-MHz frequency band. It includes HSCSD, GPRS, and EDGE (with an improved modulation scheme). GSM is the de facto leading cellular standard in the world. According to the GSM Association, GSM has reached nearly 500 networks worldwide in 2001. Since many GSM network operators have roaming agreements with foreign operators, users can continue to use their mobile phones when they travel to other countries. A number of U.S. operators are using GSM; for example, AT&T has built a GSM overlay network to IS-136, Voicestream, Cingular has a nationwide GSM 1,900-MHz network also. The GSM system architecture is shown in Figure 3.7 [19].
GSM Core Network Components
main functional entities:
The circuit-switching system contains five
1. The mobile services switching center (MSC) performs the telephony-switching functions for the network. It controls calls to and from other telephone and data communications systems, such as the PSTN, ISDN, public land mobile network (PLMN), and public data networks and various private networks as well.
CSE
EIR HLR/AC
CAP A GSM BSS
MAP MSC
Gb
SGSN
ISUP
GTP
CSE = CAMEL server CAP = CAMEL application part MAP = Mobile application part ISUP = ISDN user part GTP = GPRS tunneling protocol A, Gb = Radio base station interfaces
G-MSC
GGSN
ISUP
IP
N-ISDN
IP networks
X.25 X.25
Figure 3.7 GSM system architecture.
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2. The visitor location register (VLR) database contains all temporary subscriber information needed by the MSC to serve visiting subscribers. 3. The home location register (HLR) database stores and manages subscriptions. It contains all permanent subscriber information, including the subscribers service profile, location information, and activity status. 4. The authentication center (AC) provides authentication and encryption parameters that verify the users identity and ensure the confidentiality of each call. This functionality protects network operators from common types of fraud found in the cellular industry today. 5. The equipment identity register (EIR) database contains terminal identity information that prevents calls from stolen or defective mobile phones. Base Station System
entities:
The base station system (BSS) contains two functional
1. The base station controller (BSC) is a high-capacity switch that is responsible for radio-related functions, such as handoffs, management of radio network resources, and cell configuration data. It also controls the radio frequency power levels in base transceiver stations and mobile phones. 2. The base transceiver station (BTS) is the radio equipment needed for serving each cell in the network. GPRS [19, 20] brings IP-based services to the mobile marketplace via tunneling and supports the convergence of data networking and mobile telecommunications. As nonvoice services begin to predominate the wireless environment, the GPRS core represents a secure carrier investment, a basis for 3G services, and an optimized transition step to 3G. A fully featured GPRS solution complies with ETSI and ANSI standards and provides full roaming support and vendor interoperability. GPRS functions as an ideal bearer platform for WAP services. Well-integrated GPRS billing solutions provide optimized control of revenues generated by the introduction of WAP services. These systems support access- and content-based billing, prepaid billing, and provide for the smooth migration GPRS Packet Network Components
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to transaction-based micropayment models. Carriers should consider any GPRS solutions ability to integrate into their current service and billing architecture. GPRS is implemented in the radio part as well as in the switching part. It is designed around a number of guiding principles: • Always-on. End-to-end packet-switching that allows the sending or
receiving of information at any time;
• High bit rates. There is a theoretical raw data rate up to 171.2
Kbpsthe effective data rates are lower (about 60 to 115 Kbps) depending on environments and mobility parameters;
• Improved usage of the radio resources. The same radio channel can be
shared between several users (GPRS);
• Simultaneous voice call and data transfer. Data can be sent or received
even during a circuit call for voice;
• Billing based on time and volume. Subscribers are billed on the dura-
tion of the call and on the number of bytes received or sent, whatever the duration (packet switched).
GPRS keeps the same radio modulation as the GSM standard, as well as the same frequency bands, the same frequency hopping techniques, and the same TDMA frame structure. In addition, it manages packet segmentation, radio channel access, automatic retransmission, and power control. The major new element introduced by GPRS is an overlay core network that will process all the data traffic. It comprises two network elements: 1. Serving GPRS support node (SGSN) keeps track of the location of individual mobile stations and performs security functions, access control, and packet transport. 2. Gateway GPRS support node (GGSN) encapsulates packets received from external packet networks (IP) and routes them towards the SGSN. Enhanced Data Rate for Global Evolution EDGE will improve GPRS. By introducing a new radio modulation, and therefore a new generation of transceivers, it will be possible to triple the bit rates from standard GPRS. A
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world-class EDGE system can be implemented through rapid and affordable software upgrades and the addition of EDGE-capable transceivers to existing base stations. EDGE also uses the existing GPRS core infrastructure and does not require the deployment of new core network elements. Because EDGE/WCDMA are based on a common GPRS core network, operators can plan a smooth and cost-efficient evolution from GSM/GPRS to 3G capabilities. In most implementations, the spectrum required to deploy an EDGE transceiver is the same as adding an ordinary GSM transceiver. Leading EDGE solutions offer broad backward compatibility with existing network hardware and software systems. GPRS or EDGE solutions do not require the addition of a proprietary network core. The GPRS core is built on interfaces that are open and fully standardized. Practically seen, EDGE offers data rates of approximately 20 Kbps per time slot, compared to approximately 10 Kbps for GPRS even in poor C/I conditions. In more favorable conditions, and when supported by intelligent radio enhancements, EDGE can deliver data rates of approximately 50 to 60 Kbps per time slot, or up to three times the expected Kbps rate per time slot of GPRS. When deployed with eight full-speed Kbps time slots, EDGE can theoretically achieve maximum data user rates of 473 Kbps. PCS
PCS is defined as a wireless personal cellular radio using various digital technologies. PCS networks exist mainly in the United States and Canada and use different standards (TDMA, IS-136, CDMA, IS-95, and GSM). The personal in PCS distinguishes this service from cellular by emphasizing that PCS is designed for greater user mobility, unlike cellular, which was designed for car phone use with transmitters that provided coverage of highways and roads. Technically, cellular systems in the United States operate in the 824849-MHz frequency bands; PCS operates in the 1,8501,990-MHz bands. PCS today is a collection of heterogeneous cellular systems with different standards. The only common basis is the spectrum plan (PCS plan), which is subdivided into a number of nationwide or regional frequency bands of different sizes. Approximately 15 countries in the Americas accepted this spectrum plan fully or partly, which allows in principle any radio access technique and network standard. This freedom led to a number of partly incompatible networks, which exist in parallel across the country. Multimode terminals need to allow cross-network mobile communications. In addition, heterogeneity increases with the allowance for system evolution to 3G.
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Meanwhile, a number of Latin American countries decided for a shared spectrum plan, which allows the deployment of standard ITU conformist networks (2G and 3G), as well as PCS networks. PMR
First-generation PMR was developed after WWII. It was typically used for communication within one organization and in a limited geographical area. The equipment evolved from heavyweight, bulky radios operating at VHF frequencies to small-sized handhelds operating in the UHF band. Several enhancements have been introduced over the years, like selective calling, status reporting, digital signaling, and data communication facilities. Usually, not enough traffic is generated to justify the assignment of exclusive frequencies, so communication channels have to be used on a shared basis. Trunked PMR and Public Access Mobile Radio
The first-generation trunked PMR made more efficient use of the spectrum by dynamically allocating radio channels in the system. As this process was controlled by a centralized unit, only reasonably sized organizations or service providers could employ the technology. The dynamic channel allocation (DCA) principle could alleviate the demand for spectrum in the existing land mobile frequency bands, but no mass user migration into trunked radio operation was reported. Major standards were Radiocom 2000, Mobitex, and MPT 1327. Digital Short-Range Radio
Digital short-range radio (DSRR) was aimed to fulfill the needs of small business PMR users. It operates on the principle of self-trunking or DCA without a centralized control unit. TETRA
TETRA, a standard for 2G trunked PMR equipment, has been completed by ETSI. This recently published standard covers voice and data applications. The European operators Dolphin Telecom and Telefónica Móviles are among a new brand of service provider expanding the profile of TETRA users beyond its historical base of public security and safety services. There is also a demand amongst fleet managers and workforces in the field, who require a mobile solution that facilitates push-to-talk, group communications, and emergency calls.
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The TETRA frequency bands of 380 to 385 and 390 to 395 MHz have been designated for emergency services, such as police and fire brigades. For civil use the bands 410 to 430, 870 to 876, and 915 to 921 MHz have been designated as preferred bands. If these are not available, the bands 385 to 390, 395 to 399.9, and 450 to 470 MHz should be used. Public-access mobile radio (PAMR) is a development that provides radio space and similar facilities for public closed user groups, such as taxi drivers, police, and health services. TETRA and TETRAPOL are in commercial use in Europe providing digital voice and data capabilities, with encryption where appropriate, with the following characteristics: • It can operate from 100 MHz to 1 GHz, but is typically deployed • • • • • • •
around 400 MHz; 25-kHz radio channels providing four time slots, each supporting 7.2 Kbps voice or data; Bandwidth on demand facility up to 28.8 Kbps, by cojoining up to four time slots; Rapid access (call setup: 0.25s), high reliability, and security; Full duplex or simplex speech; Call prioritization; It allows group-wide communications and real-time conferencing; In its direct mode, radio terminals communicate directly by using single frequencies.
The United States, Australia, and South Africa are also considering TETRA for PAMR. A half-rate speech facility is under investigation to double useful voice capacity. IEEE 802.16 Broadband Wireless Access
In April 1999, the IEEE P802 LAN/MAN Standards Committee announced another formation: the P802.16 Working Group to develop standards for broadband wireless access (BWA) [21]. The group concentrates on the standardization of fixed BWA systems, focusing on those operating in the licensed spectrum near 30 GHz, but the standards are intended to be broadly applicable from 10 to 66 GHz. Developed by a study group involving 97 people from over 70 companies, the P802.16 Working Group objectives include both a coexistence specification and an air interface enabling the
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transport of data, voice, and video services. The result is expected to bring numerous manufacturing advantages, providing an industry with the potential to compete successfully by providing alternatives to wired access links that utilize fiber, cable, or telephone lines. The expected standards will concern broadband wireless access systems, and, although wireless, will not deal with mobile systems. It is rather intended as an alternative to wired last-mile access links and will use fixed base stations to provide broadband data to businesses or homes. The term broadband refers to telecommunication that provides multiple channels of data over a single communications medium, typically using some form of frequency or wave division multiplexing. The base stations may be either terrestrial, in orbit, or mounted on airplanes or dirigibles in the stratosphere. The customer terminals can carry two-way communications for Internet access, digital video, telephony, and other services. As large blocks (on the order of 1 GHz) of microwave and millimeter wave spectrum are becoming available, BWA networks are being deployed and developed in many countries throughout the world. Most of the frequency allocations are near 24, 28, 31, or 40 GHz. Many companies believe that the cost and performance of such systems will be competitive with wired broadband access networks. In the United States, BWA systems operating near 24 and 38 GHz began commercial service in 1998. The charter for the BWA Study Group was to develop new projects leading to BWA standards that do the following: • Use wireless links with microwave or millimeter wave radios; • Use licensed spectrum; • Are metropolitan in scale; • Provide public network service to fee-paying customers; • Use point-to-multipoint architecture with stationary rooftop or
tower-mounted antennas; • Provide efficient transport of heterogeneous traffic supporting QoS; • Are capable of broadband transmissions greater than 2 Mbps. Local Multipoint Distribution System and Multichannel Multipoint Distribution System
These wireless access technologies provide two-way high bandwidth connections for stationary use. Various countries are adopting the Local Multipoint Distribution System (LMDS). The frequency range of LDMS lies between
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24 and 31.3 GHz in the United States. A key advantage of these systems is that they can be used for symmetric and asymmetric traffic applications. For example, LMDS permits data rates of up to 1.54 Gbps downstream and up to 200 Mbps upstream. These bit rates indicate that LMDS is generally a system for larger computer applications. The Multichannel Multipoint Distribution System (MMDS) was originally used for pay-TV applications. The bit rates are 300 Kbps to 3 Mbps upstream and downstream. It operates in the 2.15 to 2.68 GHz range. The IEEE 802.16 standard specifies the physical layer and MAC layer [22]. IMT-2000/UMTSA Global Achievement
Second-generation wireless mobile systems are still constrained in terms of the data rate they can offer and their flexibility to manipulate a multiplicity of multimedia services. There is a growing need for a system capable of managing and delivering a much wider range of information services to the mass market. Worldwide understanding of this objective led to the major new 3G mobile system being developed within the framework that has been defined by the ITU, known as IMT-2000. A fundamental goal of IMT-2000 is to provide universal coverage and to enable seamless roaming between multiple networks. In this regard, IMT-2000 is far more than just an improved version of todays 2G systems. The two landmark decisions that were taken by ITU member states in 2000 to formally approve IMT-2000 standards and identify additional spectrum for 3G systems have given the entire mobile industry clear signals to realize the dream of global wireless systems. The licensing process based on the initial IMT-2000 bands gained momentum in many countries across Asia, Europe, and Latin America. Commercial operations in Asia and Europe commence between 2001 and 2002. ITUs vision that people should be able to communicate anytime and anywhere globally is about to become a reality. In Japan, Korea, and in Europe, research and standardization activities began in the early 1990s and were aimed to release the first set of standards before 2000 in order to meet the introduction deadline in 2002 [23]. The standardization framework of IMT-2000 has been defined by the ITU as an open international standard for a high-capacity, high data rate mobile telecommunications system incorporating both terrestrial radio and satellite components. The main focus of IMT-2000 is the air interface. UMTS is being standardized in an IMT-2000 framework, whereby the specifications are developed by 3GPP, a global standardization initiative created in December 1998. The project is based on a concept facilitating coordination
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between regional standardization organizations, forums, and other industry groups. Ownership of the specifications is shared between partners. In cooperation with regional and national standardization bodies around the world, 3GPP aims to produce detailed standards to satisfy growing market needs for global roaming and service availability. The focus of the 3GPPs standardization work is the entire network, comprising radio and core network elements as well as end-user equipment standards, smart cards, and the integration with the Internet. The partner standards development organizations are ETSI, ARIB, TTC, the T1 Committee, the Telecommunications Technology Association (TTA), and the China Wireless Telecommunications Standards (CWTS) Institute. The origin of UMTS can be traced back to the mid-1980s. As thinking on the post-2G environment began to be stimulated, the European Commission (EC) published a green paper and follow-up report that assumed a regional focus for developments in telecommunications. In 1985 the EC instigated a pan-European research program known as Research and Development in Advanced Communications for Europe (RACE), to consolidate requirements and propose solutions for the communications environment at the end of the millennium [18]. Figure 3.8 shows the collaboration between ITU and external organizations in the development of IMT-2000 radio interface framework standards, which were approved in Istanbul as ITU-R Recommendation M.1457 [24]. It should be mentioned that another 3GPP called the 3GPP2 was established by the U.S. TIA in collaboration with CWTS, ARIB, Japans TTC, Koreas TTA, and the U.S.s Standards Committee T1, in order to achieve international cooperation in the development of technical specifications based on cdma2000. 3GPP and 3GPP2 maintain a relationship for interoperability between their standards. UMTS is an important part of wider initiatives to satisfy the needs of corporate users and the mass market. Complementary work is underway throughout the UMTS Forum and other industry organizations on every aspect of the emerging information society: multimedia, information, and content. UMTS seeks to build on and extend the capability of IMT-2000 mobile, cordless, and satellite technologies by providing increased capacity, data capability, and a far greater range of services using an innovative radio access scheme and an enhanced, evolving core network. In early 1998, the EC published the EC Proposal for a European Parliament and Council Decision on the Coordinated Introduction of UMTS
Technologies
ETSI
Consortial Europe partnership 173 companies*
ARIB
Japan 37 companies
TTC
18 companies
TTA
Korea 25 companies
T1
IMT-F
3GPP
UWCC
USA
TIA
22 companies
CWTS
China 9 companies
83
C IMT-DS IMT-TC
ITU
IMT-SC
-MC IMT
3GPP2 IMT-2000 radio interfaces Standards development organizations
*Individual members Figure 3.8 Industry collaboration on IMT-2000 radio interfaces. (Source: ITU, 2000.)
to ensure that EU member states undertook the appropriate steps to implement the ERCs decision on spectrum allocation. This, in combination with the existing licensing directive, will ensure UMTS services can commence in 2002. In the United States, any licensee is free in principle to implement any technology it chooses. Potential candidate bands for 3G technologies are the PCS bands, the remaining IMT-2000 bands, and parts of the UHF TV bands. Key Technologies
This section describes some of the key technologies essential for the successful introduction of UMTS. Figure 3.9 gives an overview on the ITU terrestrial radio interfaces and core networks belonging to the IMT-2000 system family. It indicates that two of the radio interface standards and two of the core network standards belong to UMTS. Ten candidate terrestrial specifications were submitted to the ITU-R TG 8/1 [18, 23]. Following harmonization initiatives between the original candidates, five were actually approved for use in the spectrum identified for IMT-2000:
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IMT-DS W-CDMA (UTRA) FDD direct spread
IMT-TC UTRA TDD TD-SCDMA time code
IMT-MC CDMA 2000 multicarrier
IMT-SC UWC-136 single carrier
IMT-FT DECT frequency time
Paired spectrum Unpaired spectrum
Flexible connection between radio modules and core networks based on operator needs UMTS
Evolved Core networks GSM (MAP)
IP-based networks
Internetwork roaming
Network-to-network interfaces
Evolved ANSI-41
Figure 3.9 ITU-IMT-2000 terrestrial framework standards.
1. IMT-DS: The FDD standard for UMTS (UTRA-FDD) based on CDMA. Several of the original ITU proposals were merged into this proposal. The standard is developed within 3GPP. 2. IMT-TC: The TDD standard for UMTS (UTRA-TDD) based on CDMA including the Chinese proposal for TD-SCDMA with a channel spacing of 1.6 MHz. The standard is developed within 3GPP. 3. IMT-SC: UWC-136 (also called EDGE) was developed for the evolution of GSM/GPRS into IMT-2000 in the U.S. 1,900-MHz bands. It contains 200-kHz and 2.4-MHz channel spacings. In Europe, EDGE is planned for the evolution of GSM in the 900- and 1,800-MHz bands. 4. IMT-MC: cdma2000 coming from the evolution IS-95this is the standard using CDMA multicarrier technology, version 1x with channel spacings of 1.25 MHz and version 3x with channel spacings of 3.75 MHz. The standard is under development within 3GPP2.
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5. IMT-FT: DECT, as standardized by ETSI, is operated in Europe at 1,880 to 1,900 MHz, the lower portion of the IMT-2000 bands. Wider additional implementation is not foreseen at this point in time. UWC-136 is more or less identical with GSM-EDGE. UWC-136 and cdma2000 are currently under development for operation in the PCS frequency bands (1,8501,990 MHz). UTRA is under development for the globally harmonized 3G frequency bands identified in the ITU radio regulations in S5.388 (1,9001,980, 2,0102,025, and 2,1102,170 MHz) within 3GPP. Implementing the CDMA and EDGE technologies in a single terminal will add to the complexity of terminals, which is further exacerbated by the difference in spectrum implementation between Europe and the United States and other countries adopting the PCS frequency plan. On the UTRA-side, compatibility with GSM will be provided from the beginning: dual-mode and multiband terminals will ease interoperability of different standards and frequency bands, respectively. For interoperability with cdma2000, however, the complexity of these terminals quickly increases with growing divergence and the cost factor should be kept in mind even though economies of scale will ameliorate the situation. It is still important to strive for worldwide harmonized frequency bands in order to keep the complexity and costs to a minimum. The IMT-2000/UMTS community has chosen aggressive time scales for the introduction of IMT-2000/UMTS in order to meet the demands of customers in the early twenty-first century. The target date for its introduction has been set to 2001. NTT DoCoMo fulfilled this requirement with the first public service take-up in the fourth quarter of 2001. To meet this deadline, UMTS followed a phased approach that allows its capabilities to be improved over time following its introduction. It is designed as an open system that can evolve to incorporate new technologies as they become available. This will allow UMTS to increase its capability much in the same way that GSM evolved from the original data capability of 9.6 Kbps to GPRS (up to 50 Kbps and eventually to 115 Kbps) and then to EDGE technology (up to 240-Kbps effective bit rates). Satellite Component
At its initial service launch in 2000, the satellite component of IMT-2000/ UMTS will be able to provide a global coverage capability to a range of user terminals. These satellite systems are planned to be implemented using the
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S-band mobile satellite service (MSS) frequency allocations identified for satellite IMT-2000 and will provide services compatible with the terrestrial systems. They are still under investigation.
3.1.4
Extended Area Networks
3.1.4.1 Mobile Satellite Systems
UC can only be complete if the low-density areas on the globe are also covered. The value of UC in these areas lies in the fields of environmental supervision, oceanic observation, and in communications for the shipping and transport industry. Satellite systems are the only means for maritime and global coverage. The goal of mobile communications from the beginning has been to enable the user to communicate while traveling on land, at sea, or in the air. Terrestrial cellular mobile systems cannot completely fulfill such requirements, thus, satellite systems are needed. MSSs are two-way voice and data communications with a handheld terminal, where the final link to the MSS subscriber is via a satellite. Satellite allows 100% outdoor/wireless radio coverage. Figure 3.10 shows an example of how an MSS system delivers a call. The call is transmitted from the user in Africa via a satellite to the nearest
Internet PSTN Internet PSTN
Mobile Internet on the sea
Figure 3.10 MSS call delivery.
Mobile Internet in the cabin
Mobile Internet on the ground
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earth station and gateway. The call is then routed over the PSTN to the United States, terminating at the called partys premises. Satellite-based radio communication systems in the last decade have been aiming to serve the needs of maritime and aeronautical users with voice and data communications using FDMA and TDMA technologies. Their evolution continues at least for Inmarsat (I, II, III, P) and a few other systems. Wideband transmission links can be offered, however, usually up to no more than 144 Kbps for mobile application. Mobile satellite communications are also distinguished by the positioning of the satellites in the orbit. Three different types of orbit constellations can be considered (see Figure 3.11): • Geostationary Earth orbit (GEO) systemsfor example, Inmarsat; • Medium-Earth orbit (MEO) systemsfor example, Globalstar; • Low-Earth orbit (LEO) systemsfor example, Iridium and
Teledesic.
The number of satellites necessary to cover the Earth fully differs depending on their altitude. Also, the choice of the orbital constellation has
GEO
MEO
LEO
Figure 3.11 Alternative system solutions satellite technology.
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to take into account not only the quality of service offered to the user, but also the feasibility and technical risk and costs of the satellites themselves and the problem of procuring and managing the number of satellites. GEO systems become very complex in view of the high number of beams needed and the long delay time for voice calls. MEO and LEO systems are complex in that they have to incorporate handoff between cells and dynamically manage the satellite-user coverage as the satellites move relative to the Earth and at a high speed. It appears from market and business investigations that satellite systems seem to be more in a niche market than in the mass market. The market forecasts from the UMTS Forum show no more than 18 to 20 million users worldwide in 2010 [25]. This will presumably lead to developing future mobile satellite systems as complements to terrestrial mobile cellular networks. The integration of the satellite component to a terrestrial network takes place via the transport and switching network. Examples are Iridium and Globalstar. Both projects use the backbone network GSM technology in order to integrate the satellite component in a seamless way. Ways to Integrate Satellite Systems into Terrestrial Mobile Cellular Networks
The definition of the interworking functionality between a satellite system and the terrestrial infrastructure determines the complexity of the solution. The number of interfaces should therefore be minimized, as well as the scope of service features. Two solutions can be seen: 1. A satellite system as a global network in the orbit (as shown in Figure 3.12). The satellite system appears from every terrestrial network as an international network with its own country code. The subscribers number in the satellite system is not bound to any country code on the ground. The calling subscriber A must always add the international prefix and country code to reach subscriber B. Automatic roaming with GSM networks is handled in the same way as between international GSM networks. 2. SAT-PCN appears as an extension of existing PLMNs (as shown in Figure 3.13). This is valid for all derivatives of GSM: GSM 900, DCS 1800, and PCS 1900. The SAT-PCN uses the country codes of the terrestrial cellular networks and gets an additional national network code for SAT-PCN. The subscribers will get a country code depending on their home base. For such solutions, a dual-mode terminal is essential. The functionality of the dual-
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Global SAT coverage with global access code
A Country 1
Coverage only via satellite
No competition
C
B Country 2
Full terrestrial coverage
Country 3
Partial terrestrial coverage
Competition field
Figure 3.12 Global satellite networks compete with terrestrial networks.
SAT coverage with country access code 3
SAT coverage only with country access code 1
A
B
C
Country 1
Country 2
Country 3
No terrestrial coverage
Full terrestrial coverage
Partial terrestrial coverage
Figure 3.13 SAT-PCN appears as extension to national networks.
mode terminal depends on how roaming will be offered: as basic nonautomatic roaming or as roaming with handover between SAT-PCN and GSM.
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Combinations of these two solutions will be possible if the SAT-PCN is used as logical extension of the terrestrial PLMN and if the operator organization allows combined business in a country. Such a combination would allow an efficient and economical radio coverage in countries with both low population density areas and cities and hot spots. Examples are Australia, former CIS states, Russia, Asia, Africa, and North and South America. In this third alternative, the SAT-PCN would be addressed by using its national prefix. It remains unclear, however, whether such a solution would be acceptable from a regulatory point of view. This configuration is shown in Figure 3.13 [26]. The ITU Telecommunications Sector (ITU-T) decided to provide the SAT-PCNs E164 country code, +881. For each of the SAT-PCNs, an additional digit will be the specific address information (e.g., ICO = +8810; Odyssey = +8812; Iridium = +8816; Global Star = +8818). The ITU-T also decided the E212 (IMSI) code to be the mobile country code (MCC) 901 for all SAT-PCN operators. Terminals
All the present satellite PCN programs use the dual-mode terminal. GSM, the most successful digital mobile standard, is considered to be the basis for such development. This means that 900-MHz handhelds (2W) should be combined with 1,600/2,400-MHz high-frequency parts and different digital processing functions. The same development could be done for PCN systems in the United States and PDC systems in Japan. In addition, multimode solutions could be considered if the customer base justified this development. Radio Frequencies for Satellite Systems
According to the decision in the radio conference WARC 2000, the assigned frequencies in the 1.6- and 2.1-GHz range allow satellite PCNs a maximum bandwidth of 16.5-MHz for both the uplink and downlink, as well as 2 × 30 MHz for the satellite component of UMTS. Teledesic, an upcoming project that belongs to the broadband radio networks, lies in the 20/30-GHz range. It is a real alternative to the satellite PCNs presently under development. It aims to be operational by 2005 and uses the switching and transport principles of radio ATDMA. It is important to note that some of these systems are complementary to their terrestrial counterparts. For example, Orbcomm is considering teaming up with mobile data operators in the United States (such as Ardis and RAM) to offer a nationwide mobile data service. The narrowband MSS systems are
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all going to offer dual-mode phones, which function with both cellular and their own systems. The broadband systems are able to offer high bandwidth service because of the availability of spectrum at high frequencies. However, since the frequency is very high, the wavelength is very short, resulting in propagation problems. Teledesic is mainly targeting areas where broadband communications will not be delivered via fiber networks or via cellular networks in the medium term. The data-only systems offer packet-switched data services between 2.4 and 4.8 Kbps, as well as fax, paging, and position location services. Their main applications are for monitoring, tracking, and controlling. These systems offer store-and-forward type services. The time delay between a message being sent and it being delivered is dependent on the location of satellites. Narrowband MSS systems will offer a range of cellular-like services, including voice, data services up to 9.6 Kbps, and a range of value-added services. For 3G networks, proposed candidates for the satellite radio component are shown in Table 3.10. Such MSS systems will deliver medium- to high-bandwidth services, mainly for fixed applications. The most important applications will be access to the Internet via high-speed data communications, as well as digital multimedia applications, such as desktop videoconferencing. Systems like Teledesic will offer data transmission speeds of up to 1.5 Mbps for stationary use; it is not yet considered for the radio part of 3G networks. The Main MSS Operators
More than 40 companies have filed with the ITU for spectrum in which to deploy MSS systems. There are a number of global narrowband MSS systems: Iridium, Globalstar, ICO, Constellation Communications (CCI), Ellipso, and Immarsat. Immarsat is currently the most successful system with approximately 300,000 users in 2001. It is continuously improved to transport data in addition to voice. Immarsat has developed a new integrated satellite communications platform that enables businesses to extend their fixed LAN into a mobile global area network (GAN). This GAN gives access to the high quality and speed of a full mobile ISDN service and, through the GAN mobile packet data service, the cost-effective flexibility of a mobile IP service. Iridium [27] was initially a consortium of manufacturers and service providers led by Motorola, operating the LEO-based MSS system. The system began offering services in November 1998 using a constellation of 66 satellites. The FCC awarded Iridium a license to offer MSS in the United States in January 1995. Iridiums first satellites were launched in May 1997.
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UMTS and Mobile Computing Table 3.10 Proposed Solutions for the Satellite Component of IMT-2000/UMTS
Project Initiator
Satellite Constellation
Air Interface
User Bit Rate
ICO
10 MEOs 10,390 km
MF-TDMA
Up to 144 Kbps
Inmarsat-4
2 GEOs at 40,000 km (1.5 bis 1.6 GHz)
MF-TDMA
144432 Kbps (portable/terminal)
Boeing
16 MEOs 20,180 km
CDMA + TDMA
(> 1 Mbps)
Celsat (Echostar)
3 GEOs
CDMA
GS-2 (Globalstar)
64 LEOs at 1.420 km + 4 GEOs
CDMA
Up to 144 Kbps
ESA SW-CDMA
Global LEO/MEO
CDMA Chiprates: 3.84 Mcps 1.92 Mcps
32-Kbps handheld 144-Kbps portable terminal
ESA SW-CTDMA
For regional GEO/MEO systems CDMA/TDMA Chiprates: 3.84 Mcps 1.92 Mcps
Up to 183 Kbps
It was the worlds first handheld global satellite telephone, data, and paging network. Iridium was taken over by the U.S. government in early 2001 and continues its service for civilian and military use. Globalstar [28] is a consortium of European, Korean, and U.S. telecommunications companies headed by Loral Space and Communications and Qualcomm. The system provides voice, SMS, roaming, positioning, and facsimile and data transmission. It consists of a constellation of 48 LEO satellites and transmits calls from wireless phones or fixed phone stations to a terrestrial gateway, where they are passed on to existing fixed and cellular telephone networks. As a wholesaler, Globalstar sells access to its system to regional and local telecommunications service providers around the world. The system was operational by 2000; however, it did not continue owing to financial problems. ICO has its roots in the Inmarsat consortium. Most of Inmarsats signatories are also direct investors in ICO. Hughes, the largest manufacturer of commercial communication satellites, is the systems prime contractor and holds a stake in the company. ICO is an MEO-based MSS system. ICOs
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constellation consists of 12 satellites, including two in-orbit spares, which will be operational by 2003. The services bit rates are up to 144 Kbps. Constellation Communications (CCI) is a consortium comprising Orbital Sciences, Bell Atlantic Global Wireless, Raytheon E-Systems, and SpaceVest. It planned to launch a 12-satellite LEO equatorial system, including one in-orbit spare by 2001. CCI will focus on both cellular and fixed markets. CCI plans to offer a global service, using an additional 42 satellites (including seven in-orbit spares), in 2003. Ellipso is a privately owned company whose main shareholders include Ellipso Private Holding, Venture First II, Israel Aircraft Industries, and The Boeing Company. Ellipso is an MEO-based MSS system based on a constellation of 16 satellites. It planned to start service in equatorial regions by the end of 2001, followed by global service in 2002. Ellipsos main focus is the fixed market. There will also be a number of GEO systems, particularly in the Asia Pacific region. The main systems are ACeS, APMT, and ASC. EAST and Thuraya will deploy MSS covering Europe, Africa, and the Middle East. The Asia Cellular Satellite (ACeS) consortium is the most advanced regional GEO player. The ACeS system was conceived and initiated by Pasifik Satelit Nusantara (PSN), an Indonesian satellite telecommunications company. The two other shareholders include the Philippine Long Distance Telephone Company and Jasmine International Overseas Company. ACeS is based on the use of one geostationary satellite. Its commercial service started in 2000. Asia-Pacific Mobile Telecommunications Satellite (APMT) was founded by a consortium of Chinese and Singaporean investors. The venture is made up of founding partners APMT Singapore (Singapore Technologies Telemedia) and China APMT, which comprises six organizations from the Peoples Republic of China. Full commercial service was expected for the third quarter of 1998. The launch of the service has now been rescheduled. The Afro-Asian Satellite Communications (ASC) is an Indian-based venture between Indian Telecom operator Essar Telecom, the Essel Group, and Videsh Sanchar Nigam Limited (VSNL), Indias international telecommunications service provider and a wholly government-owned company. ASC aims to launch one GEO satellite to cover mainly Eastern Europe, Africa, and Asia Pacific. Issues related to financing the ASC venture, however, have put a question mark over the whole project. The Thuraya Satellite Telecommunications Company was established in January 1997 in Abu Dhabi, UAE, as an autonomous body. A number of regional telecommunications service providers and Gulf-based investment
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companies have bought into the project with the partner list now numbering 15, including Etisalat, its founder and the United Arab Emirates national telephone company. Thuraya intends to use a single operating satellite, although a second operating satellite is planned if extra capacity is required. Euro-African Satellite Telecommunications System (East) is a joint venture between Matra Marconi Space and Digimed, a fully owned subsidiary of the Cyprus Telecommunications Authority. The project uses two colocated satellites using L-band for mobile services and Ku-band for fixed village booth phone type applications. Fixed services are expected to be up and running by the last quarter of 2002. This should be followed by the introduction of East mobile services by the end of 2003. Most of these systems will use spectrum at 1.6 GHz. These systems represent 2G GEO-based MSS systems. Compared with 1G systems, such as Optus and AMSC, they will use powerful satellites with multiple beam antennae, enabling user terminals to be handheld. Other systems include AMSC, OmniTRACS, and Planet 1. American Mobile Satellite Corporations (AMSC) SkyCell satellite services [29] deliver dispatch, voice, and data communications to businesses with remote or mobile situations. It provides a nationwide two-way radio network for dispatch communications, circuit-switched data transmission, telephone connectivity, and Group 3 fax across the continental United States, Alaska, Hawaii, and the Caribbean, and their coastal waters. Qualcomms OmniTRACS [30] is a satellite communications and tracking system. It is promoted as an interactive information management system that includes two-way mobile communications, satellite tracking, and fleet management software, and enables real-time messaging, performance monitoring, and systems integration. Both AMSC and OmniTRACS are targeted mostly at the long-haul trucking industry. Their cost is high and data rates are severely limited. Comsat [31] provides worldwide satellite telecommunications by using the global INTELSAT and Inmarsat satellite systems. Comsats personal mobile communications service Planet 1 uses portable, notebook-sized satellite telephones to provide seamless voice (4.8 Kbps), fax (Group 3), e-mail, and data communications (Hayes compatible data with 2.4 Kbps) on a global basis. Global Positioning System
The global positioning system (GPS) is a satellite-based navigation system, which is not to be used for two-way wireless communication. It is mentioned because it enables worldwide automatic localization for everybody and
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anything, and, as such, is an important element for UC devices and location-based services. A new project called Galileo, which is similar to GPS, has been initiated by the European Union. It should be ready for service in 2006 and 2007. The GPS Receiver The GPS receiver communicates with notebooks, handheld PCs, or PDAs. Connection is usually established by the RS-232 interface or via infrared [32]. The Handheld Navigator The Handheld Navigator is a GPS receiver for
positioning that includes additional technology for car navigation, mapping, and agricultural applications. It provides a navigation screen and can take up map memory cards with detailed street maps. Zooming and other features are offered by this product [33]. 3.1.4.2 High-Altitude Platform Stations
The World Radiocommunication Conference 2000 (WARC 2000) decided in Resolution COM 5/13 upon the use of high-altitude platform stations (HAPS) to provide IMT-2000 in the 1,8851,980-, 2,0102,025-, and 2,1102,170-MHz frequency bands in region 1 (Europe, Africa) and region 3 (Asia-Pacific), and the 1,8851,980- and 2,1102,160-MHz frequency bands in region 2 (North and South America). HAPS are physical platforms or flying objects (e.g., a zeppelin) in a quasigeostationary position approximately 21 km in altitude (in the stratosphere) (see Figure 3.14). Built-in radio base stations shall be capable of supplying an area of 150 km up to 1,000-km diameter with radio coverage. Directional antennas shall provide the deployment of spot beam radio cells of a high quantity. HAPS can be seen as an option or extension of terrestrial mobile cellular systems. Sky station systems seem to be the first products in this market, built by an industry group including Lockheed, Alenia Spazio, Dornier, Thomson CSF, United Solar Group, and Airship Technologies Systems, United Kingdom. Two-Way Paging Services
Two-way paging services (including American Mobile and Bell South), such as Pagenet, Mobitex and Skytel in the USA, offer limited bandwidth with excellent coverage, but as with the truly national networks, cost is high and they are designed primarily for small e-mail messages and low-intensity applications, such as daily status checking. Motorolas Reflex pager network will allow bit rates up to 144 Kbps.
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Stratosphere
Base station
21 km
UAC (75-km diameter)
SAC (150-km diameter) RAC (600 km diameter)
UAC = Urban area coverage SAC = Suburban area coverage RAC = Regional area coverage
Figure 3.14 HAPS.
3.1.5
Other Technologies
For the sake of completeness, we will now describe briefly some other popular technologies like infrared, a wireless but not truly mobile communication technology, and IEEE 1394/FireWire, a wireline serial bus technology for consumer electronics. 3.1.5.1 Infrared Data Association
Infrared connectivity provides wireless interoperability between mobile communication devices. The Infrared Data Association (IrDA) [34] is an international organization that creates and promotes interoperable, low-cost infrared data interconnection standards that support a walk-up, point-topoint user model. The standards support a broad range of appliances and computing and communications devices. After overcoming initial problems with drivers, lack of support from Microsoft, and neglect of notebook manufacturers, IrDA could establish itself because of its capability to connect handhelds and infrared-enabled mobile phones to notebooks and PCs. This technology basically enables two-way cordless infrared light transmission, and, as such, offers only limited advantages for UC scenarios: • The receivers and transmitters must be in direct line of sight of each
other. This reduces the amount of flexibility you have for movement
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within the room without interrupting the signal. Unlike RF, you cannot cover the receiver or put it anywhere where the direct line of sight will be blocked. • It is capable of indoor or evening use only. • High-intensity or fluorescent lights cause interference. • Large areas require multiple emitter panels, which will increase the
cost of the system.
• Quality varies with the company.
3.1.5.2 IEEE 1394 and FireWire
UC connectivity also encompasses wireline technology, which is useful for comparison with wireless technologies (e.g., regarding bit rates and applications). The technologies IEEE 1394 and FireWire are very similar. IEEE 1394 is a wireline high-frequency transmission standard for plugnplay and high-speed serial bus connections between PCs, storage and peripheral devices, and digital consumer electronics. IEEE 1394 will be used in PCs, PC peripherals, digital TVs, camcorders, and other consumer digital electronics equipment. The IEEE 1394 bus protocol supports both isochronous and asynchronous transfers over the same set of four signal wires, offering the ideal solution in connectivity for all multimedia applications and home networking needs. FireWire is Apple Computers version of the IEEE 1394 highperformance serial bus standard for connecting devices to the personal computer. FireWire provides a single plug-and-socket connection on which up to 63 devices can be attached with data transfer speeds up to 400 Mbps. The standard describes a serial bus or pathway between one or more peripheral devices and computers. FireWire and other IEEE 1394 implementations provide the following: • A simple common plug-in serial connector with a thin serial
cable, hot-plug, and plug-and-play capability without disrupting the computer;
• A very high bit rate that will accommodate multimedia applications
with 100 and 200 Mbps.
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In time, IEEE 1394 implementations are expected to replace and consolidate todays serial and parallel interfaces, including Centronic parallel, RS232-C, and SCSI. The first products to be introduced with FireWire include digital cameras, digital video discs (DVD), digital video tapes, digital camcorders, and music systems. Because IEEE 1394 is a peer-to-peer interface, one camcorder can dub to another without being plugged into a computer. 3.1.6
Technology Positioning and Comparison
In this section we try to position and compare the described network technologies. First of all, we may state that there are a number of technologies with different standards for more or less the same services. It will be left to the market to decide which technology will best meet users demands. In the HAN, WPAN, and WLAN market, we see a number of technologies sharing the same unlicensed frequency bands. Given that frequencies will be unlicensed, and that owners of individual premises rather than government authorities will grant installation permissions, business models may differ radically from those of public telecommunications networks. Some carriers may see this as a threat and actively oppose it, while others may see it as a powerful complement to their current technologies. This market may go up to the order of several hundred million units over the next few years. Unfortunately, the superseding technology could probably occupy spectrum in the same environment as other technologies, thus degrading their performance. Interference between coexisting systems in the same band because of different radio schemes is an additional burden. In order to avoid this, it is hoped that in the long run, WLANs will migrate to 5 GHz, which may eliminate most coexistence problems. The question of interoperability in this sector can only partly be answered in a positive way. In the field of wide area technologies, the overall system aspects have an important role. They also come into play for pure radio-related interoperability matters, especially if users roam internationally. In contrast to the HAN, WPAN, WLAN sector, here there are only two competing system standards, both encompassing different radio (and core network) and, consequently, also terminal solutions. Both are operating in separated licensed frequency bands per operator, allowing exclusive use of radio technology in each band. This helps to avoid interference and coexistence problems. In some countries, however, where frequency bands are not bound to a certain standard, considerable guard band loss between adjacent bands has to be accepted. This leads to less efficient spectrum utilization. This happens in various American countries, where the frequency license allows mixed
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deployment of 2G and 3G systems, even with different radio standards. The impact on the market is fragmentation because of subdivided standards use. A first conclusion is related to the 3G market: it is the existing footprint of 2G system technology. GSM, for example, has reached (with some exceptions) worldwide coverage. The backward-compatible UMTS allows seamless transition from GSM to 3G with global roaming and interoperability. It will be difficult for the competing cdma2000 technology, which is incompatible to GSM and UMTS as well as to IS-136, to play an equivalent role on the marketplace. It can be foreseen that IS-136 will migrate to UMTS and not to cdma2000 as there are different migration paths from IS-95 to cdma2000, compared to GSM and IS-136 to UMTS. In the sector of extended area networks with satellites and HAPS, there still exists a situation of many singular projects trying to catch a market share. The total market, whether regional or global, has too many obstacles on the regulatory sidefor example, both the cross-border circulation of terminals and the low user potential may not justify network investment. However, sufficient spectrum is globally available and, according to ITU regulations, practically no license fees exist to drive up the costs for frequencies. It has to be said that a consolidation of the various radio interfaces would be most beneficial for all projects. Then, a business plan for a satellite IMT-2000 project could be positive. A second conclusion is the issue of spectrum for new technologies. The allocation of new frequency bands for 3G is important. Many states in the world follow the ITU recommendation this way. Presently, it is only possible outside North America. For WLANs, HIPERLAN, and WPANs, new spectrum in the 5-GHz range is under investigation. The dominance of GSM and WLANs in the market today promises UMTS and IEEE WLANs a far larger market compared to other technologies. Bluetooth can be seen as complementary to GSM and UMTS or cdma2000. In Europe, Africa, and Asia Pacific, there will be harmonized bands for UMTS-based 3G network technology. In other parts of the world, there may also be cdma2000. The third conclusion relates to bit rates and capacity. They are determined by radio network technology, radio dimensioning, and frequency bandwidth. Each of the radio techniques has its own bit rate limits, although it is certain that upgraded 2G systems are closer to their limits compared to 3G technologies, which are in the beginning of their life cycles. Bit rate and capacity are essential factors for radio systems. The potential of wideband CDMA with a frequency bandwidth of three times more than IS-95 or 25 times more than GSM is a clear indicator for more capacity. WLANs, HIPERLANs, and WPANs are also using wide frequency bandwidth from
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111-MHz radio channels, but they allow higher bit rates than 3G. They will be used, therefore, mainly in the business sector. The market requirement is a main point in a scenario, where a trade-off between bit rate and traffic capacity has to be made. The overall limitation is the available frequency spectrum that the operator has. Thus, it has to be decided to start with market-acceptable bit rates that provide sufficient traffic capacity for a good business development. It may be assumed that WAN applications will probably provide 64 to 384 Kbps for the majority of applications. A final remark should be made regarding WPANs, which are mainly for stationary and quasistationary use. HomeRF and Firefly are intended for networking mobile devices to PCs anywhere in the home. The HomeRF Working Group and the BSIG are doing joint work to define interoperability specifications. Bluetooth will become integrated over time into smart phones, PDAs, and laptops, and will be combined with wide area wireless technologies. Some countries still need to adopt this integration allowance into their regulatory environment.
3.2 UMTS Support for UMTS comes from the UMTS Forum, a global industry association with over 250 members [35], and more generally from worldwide industry discussions worldwide that favor UMTS as a concept that goes beyond IMT-2000. This technology integrates essential elements from the Internet with the IMT-2000 radio access and core network. In the mediumto long-term, it will use Internet-based protocols according to IPv4/v6 throughout the network. This convergence with the Internet model allows new servicesUMTS will therefore be able to provide more services than just mobile radio networks in the past or wireless access to the Internet. UMTS is a wideband, circuit- and packet-based transmission system of text, digitized voice, video, and multimedia with data rates up to (and possibly greater than) 2 Mbps. It aims to offer a consistent set of services to mobile computer and mobile phone users no matter where they are located in the world. Based on GSM communication standards and endorsed by major standards bodies and manufacturers worldwide, UMTS has become the dominating 3G standard for mobile userseven before its introduction in 2001 and 2002. Once UMTS is fully implemented, computer and phone users can be constantly attached to the Internet as they travel and, as they roam, have the same set of capabilities no matter where they are traveling. In later development stages, users will have access through a combination of
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terrestrial and satellite wireless interfaces. Until UMTS is fully implemented, users can have multimode devices that switch to the currently available technologies, such as GSM 900, GSM 1800, GSM 1900, or others. The frequency spectrum for UMTS has been identified as terrestrial frequency bands 1,885 to 2,025 and 2,110 to 2,170 MHz for like IMT-2000 systems, and 1,980 to 2,010 and 2,170 to 2,200 MHz for the satellite part of UMTS systems. The new air interface using WCDMA will offer superior performance in relation to GSM in terms of higher data rates and capacity. The second major distinguishing feature in contrast to GSM is its IP-based network architecture, which supports both voice and data services via packet transport and switching. GPRS, the first stage of service and network evolution from todays GSM systems to commercial UMTS networks, already meets UMTS goals, such as global roaming and personalized voice and data services. The WAP-service from GSM and i-mode from PDC are examples of its entry into the Internet world. UMTS, however, allows transparent wireless Internet access. It will bring Internet developments in a new direction characterized by mobility, personality, location dependency, and high bit rate access. The reasons are as follows: • Mobility allows HTML and XML content delivery and m- com-
merce.
• Person-related communication allows the development of cus-
tomer profiles and the distribution of value-added information to customers.
• Location information opens up a new service segment to deliver
context-specific services combined with location and personal profiles.
The question arises as to which services will result from UMTS. It is clear that a single killer application will not emerge; however, the mobile Web could be a powerful service creator. UMTS enables many services, some of which originate with 2G and will become more affordable using 3G [e.g., the enhanced message service, (EMS)]. Services that already exist on the Internet will be greatly improved with location, interactivity, mobile multimedia, and customer segmentation based on lifestyle management. The demand for increased personal productivity will also be of importance. The blurring of boundaries between business and consumer markets, and between work and home, will continue.
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Table 3.11 indicates the way potential UMTS services relate to Internet and intranet applications and protocols and to their functional elements ISP, portal, and the application-specific servers. The market value of a potential service can be estimated by considering aspects of service use: the number of sessions, the traffic volume, the QoS (real-time interactive or delaytolerant), and, of course, the willingness to pay for the service. Such estimations will have a considerable impact on the planning and dimensioning of the UMTS network elements that deal with the services specifically. The ISP function seems to be required for nearly all future services. Its positioning depends on how long circuit-switched transport will be used. There is also high value in the portal function: the Japanese experience with i-mode indicates that more than 50% of the service sessions are via their portal function. Another value can be seen for e-mail, SMS, and instant messaging services: E-mail is about to dominate in the wireline Internet, SMS dominates in the mobile networks, and instant messaging is emerging on the Internet. It is not visible yet that they will merge, but they will certainly be linked together. The role of database download or streaming of audio (MP3) and video (MPEG-4), and how they will be transported, needs to be discussed further.
Table 3.11 UMTS Services and Their Relation to the Internet and Intranets Service Category
Session Type
Protocols
Internet Elements
Location-based infotainment edutainment
WWW
HTTP, WML cHTML, xHTML
ISP, portal, servers
Intranet access (mobile VPN), All typestransparent mobile office, mobile tunnel commerce
IP, higher layers ISP, firewall server, transparent corporate portal
Internet access
All typestransparent tunnel
IP, higher layers ISP, portal transparent
Multimedia messaging
SMS, e-mail, downloading
SMTP, SMS, IP
ISP, e-mail, SMS-server
Audio, video doc. download
File transfer, streaming
MP3, MPEG-4, FTP, IP-based
ISP, portal, database server
Voice, real-time audio, video
Interactive/dialog streaming/one-way
SIP
Media gateway
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It is for certain that UMTS will embrace functions from the Internet model in addition to functions from the traditional model in telecommunications, which was developed for point-to-point and station-to-station twoway communications. In order to accomplish this convergence, additional network elements are needed as an integral part of the UMTS concept. The new elements are identified in the context of information-based services: the ISP function, portal operation with transaction-switching functions, the content-based billing functions, and possibly also the application service provider (ASP) functions. They are shown in Figure 3.15. The convergence point for supplying information and entertainment to the end user will be the mobile multimedia portal, which will be the end users preferred point of entry into and interaction with IP-based services and content. The portal will also aggregate the content and search for user-specific information. The mobile multimedia portal will perform applications-oriented switching in the future. 3.2.1
Value ChainDevelopments Towards Information-Based Services
The traditional telecommunications network value chain is characterized by the establishment of a physical (circuit-switched) or virtual (packet-switched) connection between two endpoints: station-to-station or person-to-person. Connection-oriented services are the basis for the charging principles of time and distance used, and end-to-end security and QoS is provided on that basis (see Figure 3.15, upper part). The new UMTS services segments require the extension of this model. Here, in addition to the user-to-user connection model, the user-to-computer or client-server model comes into play (see Figure 3.15, lower part). This can be achieved by providing access connections via a circuit- or packet-switched network from a user terminal and then, in a second step, building up a session to get the content. With the Internet, the terminal user has an account with an ISP or with a corporate IP network server (intranet server). Transparent access to the ISP is considered as a tunnel: It is the typical ISP access via the fixed telecommunications networks (PSTN or ISDN). In the UMTS architecture, it is foreseen that IP protocols will be stepwise implemented via software releases in the access and core network. The result will be a UMTS-ISP function that will provide general IP access tunnels to the Internet or intranets for all mobile users. As is shown in Figure 3.16, the migration to the integrated ISP function is already underway, being directed by the global standardization project 3GPP, which defines three steps:
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UMTS and Mobile Computing End-to-end connection security, QoS, billing
Terminal A
Radio access network
Access + transport network (e.g., PSTN)
Transport network (e.g., GSM, IS41)
Terminal B
Traditional services model (voice, fax, data, SMS)
Terminal
Radio access network
Transport network
ISP
Portal
Content
Content-related services model (WWW, e-mail)
Figure 3.15 UMTS combines the traditional and new value chain.
1. UMTS will provide a GPRS-based core network overlay for IPtransport in addition to the existing upgraded GSM circuitswitched core network. The function of GPRS is to provide IP access via pipes (tunnels) from the mobile terminal to an ISP in the Internet or to a corporate network ISP. The ISPs may be attached to either the visited or home GPRS network. The GPRS core network will use the same radio interface as is used for circuitswitched services. This allows mobile terminals with GPRS to be compatible with mobile terminals without GPRS using circuitswitched tunnels. UMTS Release 99, sometimes called Specification Release 3, introduces the new UMTS radio network, the universal terrestrial radio access network (UTRAN), with both FDD and TDD modes. The basic structure of the core networks will not change much from that of GSM with its GPRS overlay. Mobility management remains more or less the same. The core network will allow IPtransport up to 384 Kbps and circuit-switched transport common for real time non-IP and IP services with 64 Kbps. The circuitswitched channels can be used to carry IP traffic with a guaranteed bit rate for the user. MMS is also defined. 2. UMTS Release 4 adds some functionality (e.g., MMS additions) but will not involve substantial changes. For unpaired frequency use in the TDD mode, the low chip rate technique TD-SCDMA is part of this release.
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3. Beginning with Release 5 (formerly known as Release 2000All IP network), UMTS will merge both the radio and the core network to a single IP network and add multimedia services based on IP. This network will include the ISP function and will therefore enable the UMTS operator to be an ISP. The details of this migration have not yet been decided upon. A migration step that is independent from the all-IP approach involves the introduction of a transaction-switching and portal function into the UMTS network. It does not require further standardization because these functions belong to the existing IETF standards. This is a necessary step for providing the mobile user still on the HTTP protocol and applications level with the new personalized access and control features for receiving information (e.g., depending on location and personal number) with the increased quality and security the user expects. For roaming between operators (e.g., internationally), a basic set of rules and standards will be necessary for portal functionality. The portal functions lie in the application layer according to the ISO model. In case of m-commerce, the portal will migrate to an applications-oriented switching platform. Figure 3.16 shows the development of the standard. Circuit-switched access, for instance to an ISP, provides a physical channel with a guaranteed bit rate during the user session. Time- and distance-dependent charging is the cost factor that hinders a market success for content-based services. In contrast, packet-switched access tunnels allow always-on with volume-dependent charging. The bit rate is dependent on the actual traffic load and therefore is not guaranteed since many users will share a common channel. Sharing a common channel is a very important concept. In UMTS Release 3 and 4, it is deployed as an aggregation of tunnels from a SGSN to a GGSN and to one or more ISPs, providing a transparent pipe through which terminals may access ISPs. This tunnel is established during the Packet Data Protocol context activation by the GPRS tunneling protocol (GTP). During this process, the terminal uses the access point name (APN) to identify the ISP with which the terminal is to register. This process will change with Release 5, where the ISP will be in the UMTS network; thus, user registration will take place there. 3.2.2
Network Architecture
As already mentioned, the initial UMTS network architecture is built upon the GSM model (see Sections 3.1 and 3.2). It is comprised of UTRAN and
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UMTS and Mobile Computing UMTS standard release
UMTS release 99
UMTS release 4
UMTS release 5 and beyond IP Multimedia (IM)
Packet
Packet-switched access tunnels to ISP
Circuit
Circuit-switched voice, data
Core network
Packet
IP SGSN/GGSN
Circuit
Circuit-switched VMSC/GMSC
Radio network
Packet
≤ 384 kbps
Circuit
64 kbps
Services
Mobile Internet ISP VoIP
All IP
All IP
Figure 3.16 UMTS standard releases and services.
the core network, along with the circuit and packet domain as well as additional service and management components. In 2000, the UMTS Forum developed the so-called extended visionmobile Internet model for information-based services. It is shown in Figure 3.17 [36]. This evolutionary step is from the GSM model to a converged model that integrates components from the Internet. Figure 3.17 shows the elements of the total value chain and indicates the degree of standardized and commercial areas of the elements involved. It is clear that a UMTS terminal will be a commercial product to a large extent. The standardized part of it will be dominated by the air interface standard, the universal subscriber identity module (USIM) standard, and the IP protocol part with encoding and decoding. The ITU framework standards, the 3GPP-specified detailed standards, and the IETF/ISO/IEC standards will also play a role. The radio and core network, as well as the network applications related to the core network (e.g., prepaid service and other intelligent network services) belong to the ITU IMT-2000 and the 3GPP standards. The ISP functions belong to the IETF/ISO standards, as do the portals. The content provision, however, is highly dominated by commercial products and de facto standards. Figure 3.18 shows the radio access network for the GSM air interface and for UTRAN. 3GPP Release 99 is comprised of both the UMTS and GSM standard for coexistence and compatibility, including roaming
Technologies Commercial
IMT-2000
107
Internet
Commercial
UMTS UMTS
Terminal
Radio network
Core network
Network applications
Portals
ISP
Content provision
Business chain Figure 3.17 Extended visionmobile Internet. (Source: UMTS Forum.)
Circuit domain
GSM radio BSC
BTS SIM
Abis
A
MSC
Gb
Node B FDD
RNC
Node B TDD
RNC lub
lucs
lups
Other PLMN
HLR, AC
UMTS radio
USIM
PSTN ISDN
GMSC
Intranet
SGSN
GGSN
ISP
Portal
Content
Packet domain Internet
Figure 3.18 UMTS architecture including GSM components (Release 99).
between 2G and 3G networks. This combination is seen as a practical case, since UTRAN radio coverage will not be available throughout the whole country over a certain period of time after network start-up. On the other hand, since dual-mode UMTS/GSM terminals will provide compatibility
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and roaming between both radio networks (see Section 3.2.7), it seems to be an economical approach. On the network side, which can be seen in the figure where the cross-connections are linked with the radio parts, lies the circuit domain and the packet domain, as well as the mobility and call control of both. GSM and UMTS services can be handled by common network elements. This enables those operators that have both a GSM and UMTS license to decide whether to configure two separate core networks (one for GSM, one for UMTS) or to combine them. Of course, not all services can be offered by both radio networks. There will be limitations on the GSM side, both technologically and service-wise. Hereto, the core network comprises the circuit domain for all circuit-switched services (mainly voice). For data, so-called bearer services are offered, which are (on the GSM side) generally up to 14.4 Kbps and for HSCSD up to n × 9.6 Kbps. The practical bit rates go up to approximately 30 to 50 Kbps. On the UMTS side, the circuit domain offers 64-Kbps bearers. They are quasitransparent bit-transport pipes for IP or non-IP service access. The packet domain provides packet-based connection-oriented transport with bit rates up to 384 Kbps (Release 99) and even higher bit rates with subsequent UMTS releases. Virtual connections are provided that allow the end user to be always on. The next element after the GGSN is the ISP [37]. The ISP function accomplishes the user registration for entering the IP-based infrastructures (domain-based addressing). This is the junction with the Internet and intranets. This function may be enriched with additional features that deal with the operators service offeringsfor example, access to improved WAP servers and similar services, which require protocol support beyond pure IP transport. Finally, the portal function is shown as another important element for UMTS. It is a key element for mobile Web services and it will be the key element for personalized user access to information and transaction-based billing (which goes beyond volume charging taking place in the transport layer). Such functions will be provided in the future. The telecommunications management network is responsible for the total management of both the packet and circuit domains, including the radio part anddepending on ownershipalso the ISP and portal functions. The Signaling and Control Plane
For packet- and circuit-switched transport services, UMTS uses the longterm IP-transport infrastructure comprised of high-speed routers with highcapacity transmission links. In the short term, as already described, a separate circuit-switched transport exists for voice and data services. Along with the
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upcoming Internet transport infrastructure, the network needs (for both the transport and switching infrastructures) an overlay network to deal with the overall multiservice and transport infrastructure signaling and control (see Figure 3.19). This signaling and control plane will evolve from UMTS Release 99, with separated physical entities for circuit- and packet-switched services, up to Release 5, with its harmonized all-IP transport and switching platform. Domain-specific routing will be needed in the beginning and will be common later; mobility management, however, will remain more or less independent from this evolution. The separation of transport and signaling control is inherent to the packet domain of UMTS, since only IP-based services should not be impacted by UMTS-specific control functions at all. Hence, the total access network including the GSM radio part and the UMTS-switching and transport domains may be regarded as an access network to the Internet. This includes global roaming with physical roaming features and user authentication as well. In addition to the signaling and control plane, a service plane deals with the network feature support, which goes beyond the described basic access and switching functions. Such features deal, for example, with the customized access for mobile enhanced logic (CAMEL) protocols to provide a
Intelligent Intelligent Network network Services services
ValueValue Added added Services services
Applications Applications
Service plane
Open service API
Signalling Signaling
Mobility Mobility
Security Signalling Security Signaling Authentication conversion Conversion authentication
Radio Radio Access access
Core Core
MGWY
Signaling and control plane
Standard network API
Figure 3.19 Layered service architecture.
Bearer plane
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virtual home environment for roaming users in their visited networks. The application program interface (API)a common programming interface should allow flexible multivendor solutions. 3.2.3
UMTS Radio Access Techniques
The ETSI decision in January 1998 [18] on the radio access technique for UMTS combined two technologies: WCDMA for paired spectrum use and TD-CDMA for unpaired spectrum useboth should form one common standard. This dual-mode approach ensures an optimum solution for all the different operating environments and service needs. The specifications for both modes were finally worked out by 3GPP and approved in December 19991 [18, 23]. WCDMA is a direct-sequence CDMA scheme using a single carrier with a bandwidth of 5 MHz. With this radio scheme, users information bits are spread over an artificially broadened bandwidth. This is done by multiplying the information bits with a pseudorandom bit stream, which is several times as fast. The bits in the pseudorandom bit stream are referred to as chips; the stream is known as the spreading code. It increases the bit rate of the signal by a ratio known as the spreading factor (typical values are 4 to 16). On the receiving side are the correlation receivers. They store exact copies of all the spreading codes. The received data stream is multiplied by these codes, and the information is selected with the same codes as used for transmission. The decoded user signal is increased by the spreading factor; this is called processing gain. Low user bit rates get a lot of processing gain with high spreading ratios, while high user bit rates get less processing gain because of their lower spreading ratios. The spreading and despreading allows all the radio base stations in a network to use the same frequency carrier (reuse 1). Terminals are responsible for strict power control so that signals from all terminals arrive at the base station with the same strength. The WCDMA spreading codes have a variable length of 4 to 512 chips in the downlink and 4 to 256 chips in the uplink. All the spreading occurs on 10-ms radio frames at a constant chip rate of 3.84 Mcps. WCDMA has two modes that are distinguished by the separation of the two communication directions. FDD employs separate uplink and 1. This radio interface specification developed by 3GPP is contained and referenced in two parts (IMT-2000 CDMA Direct Spread and IMT-2000 CDMA TDD) of the new ITU-R Recommendation M.1457 [24] which was approved by the ITU-R Radiocommunication Assembly (RA-2000) in May 2000.
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downlink frequency bands with constant frequency offset between them. TDD has the uplink and downlink direction in the same band and timeshares the directions with a guard period in between. Both modes will be used in parallel and will provide the user with the benefit of both radio access principles in overlapping application scenarios. The access scheme for both modes is shown in Figure 3.20. The combination of both modes enables the operator to provide radio coverage in all environments: at home, in the office, and in the public area. The two UMTS modes enable all kinds of spectrum to be obtained (paired for FDD and unpaired for TDD) at enhanced efficiency, and they are both accepted by regulators, globally acting operators, and vendors. FDD Mode
The FDD mode is intended for high-speed vehicular and low-speed pedestrian use in public macro- and microcell environments with typical data transfer rates of up to 384 Kbps. FDD is especially suitable for wide area coverage due to its potentially high reach. Furthermore, through the use of spreading capabilities, FDD efficiently adapts to the varying user data rates required for diverse applications and also to asymmetric traffic as long as it is balanced in total for uplink and downlink spectrum utilization. Higher bit rates beyond 384 Kbps are also possible and will be offered in microcell
Time
Power density
Power density
Time
Channel bandwidth
Channel bandwidth
WCDMA
TD/CDMA (HCR) TD/SCDMA (LCR)
FDD mode
TDD mode
Figure 3.20 UTRA adaptive modes: (a) FDD mode, and (b) TDD mode.
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environments. Their spectral efficiency depends on low mobility applications (e.g., pedestrian use up to 10 km/hr). FDD is especially suitable for the following: • Public macro- and microcell environments; • Licensed applications; • Symmetrical access using identical frequency bandwidths for uplink
and downlink;
• Up to 144 Kbps with high mobility (e.g., fast trains up to 500 km/hr); • Up to 384 Kbps for mobility up to 120 km/hr; • Higher bit rates in cells dedicated for low mobility use. TDD Mode
The TDD mode is applicable basically in all environments. It provides distinct advantages in micro- and picocell environments (e.g., for licensed and unlicensed use, for cordless applications, and for wireless local loops). TDD is especially suitable for environments like city centers, business areas, airports, shopping malls, and fairs, where applications tend to create highly asymmetric traffic (e.g., Internet Web access). The reason is that it facilitates the particularly efficient use of the available unpaired spectrum and supports data rates of up to 2 Mbps for low mobility use (pedestrian). TDD is also ideal for corporate networks since it provides the same services on the corporate site as it does outside in combination with FDD for wide area coverage with separate, simplified network planning (practically no cell breathing effect) on the campus. TDD is especially suitable for the following: • Public micro- and picocell environments; • Licensed applications for outdoor and indoor use; • Unlicensed private or corporate applications; • Asymmetrical access within one single frequency band; • Up to 2 Mbps with low mobility (pedestrian) and stationary
applications;
• Up to 384 Kbps with mobility up to 120 km/hr.
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3.2.3.1 Deployment Aspects of the Two Operation Modes
The FDD mode uses two identical amounts of paired spectrum for uplink and downlink, separated by a center gap called the duplex distance (see Figure 3.21). The best frequency utilization is achieved when there is identical traffic in both directions. The basic bandwidth is 5 MHz. The minimum spectrum assignment for uplink and downlink is 2 × 5 MHz. Asymmetrical spectrum allocations for FDD may be consideredfor example, as a combination of one uplink channel with two or more downlink channels; however, only a very limited flexibility in coarse steps can be achieved. The usage of such arrangements places additional burdens on terminal implementation (e.g., resulting from the necessary capability to deal with variable duplex spacing). The TDD mode uses only one (unpaired) piece of spectrum for uplink and downlink (see Figure 3.21). Both transmission directions are dealt with sequentially; they are separated in time. The flexible and adjustable allocation of time slots, which is required for each direction, allows coping with traffic asymmetries in a flexible way. The TDD specification with 15 time slots (high chip rate) allows for capacity variations [downlink to uplink (DL:UL)] between 14:1 and 2:13. The low chip rate TDD mode allows variations from 11:1 to 1:11. For large traffic asymmetries (for example, with significantly higher traffic in the downlink than in the uplink) the FDD spectrum is not used Energy
FDD
Uplink channel
Downlink channel Frequency split
Frequency
Energy
TDD
Uplink channel
Downlink channel Time split
Figure 3.21 FDD and TDD. (Source: Siemens.)
Time
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UMTS and Mobile Computing
effectively (uplink band being partly empty). For high traffic asymmetries (e.g., 10:1) and in a given amount of spectrum the TDD mode can theoretically (asymptotically) carry up to nearly twice the traffic capacity compared to FDD. This feature applies to the link, cell, cell cluster, and network levels. The TDD mode can thus create higher revenues for operators for a given spectrum width and the related spectrum costs. The spectrum requirements with asymmetric traffic conditions are lowest for network implementations based on the TDD mode alone or with a mixed FDD/TDD approach; they are significantly higher when only the FDD mode should be used. 3.2.3.2 Bit Rates and Traffic Capacity
The performance of a radio transmission technology cannot easily be calculated. When using mathematical formulas, too many parameters play a role in the radio field and the complexity of functions increases. To achieve spectral efficiency figures, many software tools have been developed by radio technology research programs. It is difficult to achieve comparable evaluation results because requirements of radio technology as well as the techniques used for radio transmission have changed over the years. Often, for a specific system, quite different numerical values of spectrum efficiency are reported because of the different scenarios adopted by the group of experts doing the investigations. It is evident that the performance of a radio transmission technology can only be compared on the basis of the same path loss model, the same traffic and environment scenario, and the same mobility model. Both uplink and downlink have to be considered, at both the link level and the system levelboth are relevant for a good simulation result. The radio technology performance for UMTS services has to be considered for many types of service: There are several service categories (see Chapter 4), which have different bit-rate, QoS, and capacity requirements. There are also different aspects from a users and from an operators perspective: • The users perspective. There is a multichannel requirementa con-
trol channel, a real-time channel for voice and video telephony (probably circuit-switched with a guaranteed bit rate and very short delay time), and a data channel with a higher bit rate demand, delay tolerant and varying QoS. In the all-IP radio network, these channels are all virtual channels.
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• The operators perspective. The total traffic capacity of the radio cell
in relation to the frequency band and a high number of users are the main required factors. Thus, the spectral efficiency factor and the number of real-time channels with guaranteed bit rate, as well as non-real-time channels, play the deciding role. In case of small cells, the impact of trunking loss lowers the capacity according to the Erlang formulas.
For circuit-switched systems that are dimensioned with the Erlang formula [38], the channel efficiency measured in channels per cell is taken into account. Each channel has a predetermined bit rate for a certain service (e.g., for voice, it is 64 Kbps in ISDNs and 13/6.5 Kbps in GSM networks [39]). Voice encoding, voice activity detection, and forward error correction are included. The spectral efficiency of the radio channel is the maximum achievable bit rate per hertz; it determines the performance of the channel. The numerical values for such systems were investigated quite often. An example can be found in [39]. The channel efficiency of GSM is calculated, also the spectral efficiency factor, which for GSM is 54 Kbps/MHz/cell. 3.2.3.3 Performance Factor Bit Rate
Discrete user channel bit rates and the number of channels were usually the basis for channel capacity estimations in 2G systems. In 3G, with its packet transport mechanisms, the total bit rate and channel capacity of a radio cell is the primary target. This capacity can be shared by a number of users who have initiated sessions and who are sending or receiving datagrams with bit rates, depending on their terminals [40]. In CDMA radio systems, the maximum achievable bit rate per user may vary in the radio cell depending on the distance of the mobile user from the base station. In the cell border, the signal-to-noise level is low, so only medium bit rates can be achieved, using appropriate modulation schemes. In the center area of the cell, a higher signal-to-noise level is available, so high bit rates can be achieved using higher modulation schemes. Such link adaptation techniques can be advantageous if packet-switched transport is used. The bit rates for a given radio channel and technology can be achieved by computer simulations. Simplified calculations based on the chip rate, frequency band width, frame structure, time slots, and modulation schemes are described briefly for the UTRA operation modes FDD and TDD.
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FDD Mode
The carrier bandwidth of WCDMA is 5 MHz, the frequency reuse factor is 1, and the chip rate is 3.84 Mcps. A radio frame has a duration of 10 ms and comprises 15 time slots. The number of chips per time slot is therefore (3.84 ∗ 106 × 10−2 s)/15 = 2,560 chips/time slot With a spreading factor of 4 and each time slot carrying 640 bits in a 10-ms radio frame, the uplink bit rate per second is (640 × 15)/0.01s = 960 Kbps With burst type 1 [23, pp. 2829; 40, p. 170] each slot can carry 488 bits instead of 640 bits, which yields the following bit rates, dependent on the different modulation schemes for the uplink and downlink: • Uplink (data modulation BPSK): 488 × 15/0.01s = 732 Kbps • Downlink (data modulation QPSK): 488 × 15 × 2/0.01s =
1,464 Kbps
With multicoding, higher bit rates can be calculated. TDD Mode
The carrier bandwidth of the TDD mode (for high chip rate) is 5 MHz, the frequency reuse factor is 1, and the chip rate is 3.84 Mcps. The radio frame has a duration of 10 ms. There is also the LCR version (TD-SCDMA), where the frequency reuse factor may be either 1 or 3, the carrier bandwidth is 1.6 MHz, and the chip rate is 3.84/3 = 1.28 Mcps. In the following example, the bit rate is calculated for the LCR TDD scheme. The 10-ms radio frame is divided into two subframes of 5-ms duration. There are seven time slots per subframe (one time slot is used for control). Two radio frames allow in total 12 time slots for user uplink or downlink traffic (e.g., 2 time slots up and 10 time slots down relate to a traffic asymmetry of 1:5). It should be noted that in asymmetric operation at least one time slot must be allocated for each direction. The 5-ms radio subframe has for each time slot 864 chips. Among the seven time slots, the first one is always allocated for signaling purposes. The time slots for the downlink and for the uplink are separated by a
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guard-period (16 chips). In each subframe there is one switching point (called midamble = 144 chips). The guard-period and the switching point both represent an overhead of 18.5%. For user traffic, 2 × 352 chips are available in total. Each data symbol is spread by CDMA code. If a spreading factor of Q = 16 is applied, the calculated number of data symbols is N = (2 × 352 chips)/16 = 44 data symbols per time slot Each of the data symbols is QPSK modulated, according to the specified radio system. It originates two encoded data bits. This leads to a user bit rate per time slot of R = (2 × N ) / frame duration = (2 × 44)/(5 × 10−3s) = 17.6 Kbps. Traffic asymmetry 5:1 means 10 time slots assigned for downlink and 2 time slots assigned for uplink traffic. If a loading factor of 0.6 is applied, the spreading figure will be 10 instead of 16. The calculation finally results in the following user bit rates: • Downlink: RD = 10 × 17.6 Kbps × 10 = 1,760 Kbps • Uplink: RU = 2 × 17.6 Kbps × 10 = 352 Kbps
In case of symmetrical traffic, the calculation would result in 1,050 Kbps for both the uplink and the downlink. 3.2.3.4 Performance Factor Traffic Capacity
One of the consequences of the WCDMA system is that maximum user bit rates cannot directly be used to calculate the total traffic capacity per cell. If link adaptation is used for IP-based traffic, bit rates may differ depending on the distance to the base transceiver station. The traffic capacity of a given radio cell for a particular technology can therefore only be a result of computer simulations. Spectral efficiency figures have been produced for UMTS/UTRA in a series of investigations with predefined and comparable analytical models. Basically three different transport classes have been investigated:
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1. For voice services of 8 Kbps; 2. For long constrained delay (LCD) data services bit rates from 64 Kbps up to 2,048 Mbps for indoor 3 km/hr, up to 384 Kbps for outdoor 3 km/hr, and up to 144 Kbps for vehicular up to 120 km/hr; 3. For unconstrained delay data (UDD) services with automatic repeat request (ARQ) and no loss of data over the radio link, the same bit rates were simulated as for the LCD services. The simulations took place on a link level and on a system level. Detailed information can be found in [23]. On a system level, three relevant UMTS environments were simulated: 1. Indoor office; 2. Outdoor-to-indoor pedestrian; 3. Vehicular environment as a macro-environment with cell site distances of 6 km. On the transport side, circuit-switched and packet-switched transport was simulated. The simulation results were approved by ETSI for submission to the ITU-R for the IMT-2000 candidate selection. The following system-level spectral efficiency factors were achieved for FDD (uplink/downlink): • Voice (50% activity): 86132/70125 Kbps/MHz/cell; • LCD: 140330/210461 Kbps/MHz/cell; • UDD: 168449/290453 Kbps/MHz/cell.
Most traffic capacity calculations use spectral efficiency factors, which are lowered in order to keep some reserve for unknown impacts in the field. For example, in [41], a factor of 80 Kbps/MHz/cell and 200 Kbps/MHz/cell is used for voice and data services, respectively. For TDD, the system level simulation results [23, Chapter 2.3] were based on the same scenarios as for the FDD mode. This means that macrocells with cell site distances of 6 km were also simulated here. The TDD mode allows the introduction of DCA, which brings a capacity gain of about 25%. In addition, smart antenna techniques improve spectral efficiency considerably. In the standard case, it was found that the downlink is more critical than the uplink. (For example, on the uplink antenna diversity can be
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applied to improve the efficiency.) Thus, only the downlink was simulated. The following simulation results were achieved for TDD/HCR downlink: • Voice (50% activity): 7048 Kbps/MHz/cell; • LCD: 62330 Kbps/MHz/cell; • UDD (with ARQ): 320642 Kbps/MHz/cell.
Note that the UDD service is seen as a packet-switched service where no loss of data is expected over the radio link due to ARQ. It works in such a way that the first data transmission is nearly uncoded. If it fails, the second transmission works with improved coding. If the second transmission also fails, only the burst with the worst bit error rate is retransmitted. After 10 to 20 retransmissions the session will be dropped. 3.2.3.5 High-Speed Downlink Packet Access
The UTRA air interface standard evolution, which is under discussion in the global standardization project 3GPP, considers packet data downlink transmission rates of up to 10 Mbps within the same carrier of 5-MHz bandwidth. For the uplink, the maximum bit rates are according to the regular standard specifications (≤ 2 Mbps). 3.2.3.6 Transport Connections in the Radio Access Network UTRAN
The WCDMA-based radio interface is capable of multiplexing different bit rates and different services over a 5-MHz wideband single frequency carrier system. The frequency reuse factor of 1 makes it necessary for the separation of user information to be done via demultiplexing of encoded data. Thus, it is effective to transport the received information on the base station via statistical multiplexing channels [i.e., those utilizing asynchronous transfer mode, (ATM)] to the radio network controller (RNC). Applying ATM to very low bit rate mobile voice streams in a mobile communications network necessitates a so-called layered cell structure, also known as ATM Adaption Layer 2 (AAL2), which multiplexes several minicells into one ATM cell to prevent degradation of the QoS due to the delay in filling out the payload of a regular ATM cell. A major impact in CDMA systems is related to soft handover in the access network, when the handset communicates with more than one base station. In order to work seamlessly, connection setup has to be performed within 100 ms or less during soft handover. Because of strict radio-level synchronization needs between soft handover legs, these AAL2 connections are required to meet strict delay and delay jitter requirements
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regardless of the type of user payload (i.e., regardless of whether voice or data is transmitted). Furthermore, AAL2 also allows a reduction of the number of transmission lines and correlated costs needed to support multiple connections to handle soft handover in WCDMA-based UMTS. In all, the ATM/ AAL2-based UMTS access network provides core-network-technologyindependent access for mobile terminals to all core networks and network services. 3.2.3.7 The Satellite Radio Component of UMTS
Besides the ITU framework satellite standards, some standardization activities exist for the satellite component of UMTS. These are based upon the terrestrial air interface WCDMA with the FDD and TDD mode. Modifications were made in the following areas: • Half-rate option to reduce the minimum carrier bandwidth from
5 to 2.5 MHzthis is necessary for coexistence with other satellite systems;
• Transmission power reduction for the downlink on the handheld
side, down to approximately 0.5W, with uplink bit rates up to 32 Kbps;
• Slow power control.
The focus in the ongoing standardization work lies on the FDD mode. The radio base station system should be directly linked with the UMTS core network via the Iu interface (see Section 3.2.2). Table 3.8 shows proposed solutions for the satellite radio component of IMT-2000 and UMTS. The radio component will use the same core network as for the terrestrial UMTS. 3.2.4
Core Network
As already briefly mentioned, the core network is responsible for registration, switching, and transport. It is based on the GSM network architecture with upgrades and modifications for new radio-related interfaces (A, Gb for GSM radio + lucs and lups for UTRAN). Backward compatibility to GSM, ISDN, and PSTN is an essential requirement for the core network elements. According to the present standardization, the UMTS architecture is split into three domains:
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1. The circuit-switched domain; 2. The packet-switched domain; 3. The IP multimedia domain. The three domains are shown in Figure 3.22. All domains are controlled by a separate control layer for mobility management, authentication, and security. A media gateway (MGW) cares about transitions to other networks (elements) where required. In the future, the ISP and portal function will possibly lead to an additional domain dealing with services and applications. As shown in Figure 3.23, the UMTS core network is partly comprised of the same network elements as GSM and the Internet (compare with Figure 3.7). Their evolution is driven by 3GPP, the largest worldwide standardization project. The first releases of the UMTS standard are defined as follows. Release 99 It is used for build-up of the initial networks. It provides general compatibility with GSM for voice and SMS and delivers data services up to bit rates of 64 Kbps for circuit-switched traffic towards ISDN, PSTN, and other PLMNs, and up to 384 Kbps for packet-switched data traffic. Access to the Internet and intranets is generally accomplished via a GPRS tunnel to the ISP using IPv4 IP headers. IPv6 dynamic address allocation should also be possible for limited IPv6 use. The Release 99 architecture is very similar
domain CS Domain
UTRAN
ISDN ISDN PSTN PSTN other PLMN, other PLMN e. g. GSM (e. g., GSM)
IMS Domain domain
PS Domain domain
Figure 3.22 UMTSbasic network transport structure.
External IP network Network Internet Internet
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3G MSC USIM
Iucs
Node B
RNC
Node B
RNC
USIM FDD
Other PLMN HLR, AC
TDD Dual mode
PSTN ISDN
3G MSC
Intranet
lups
SGSN
GGSN
ISP
Portal
Content
lub
MSC, SGSN, and GGSN = enhanced for UMTS
Internet
Figure 3.23 Core network Release 99.
to the GSM architecture with GPRS except that, in the latter, network elements can be interconnected optionally via Internet routers and IPtransport is provided up to the ISP. The circuit domain is based on enhanced GSM MSCs, and the packet domain is built on enhanced GPRS support nodes (GSNs). The HLR holds subscriber data and supports mobility in both domains. Two distinct instances of the so-called Iu interface are used between the access and the core network. The hybrid nature of UMTS Release 99 is most obvious in the transport and call control planes. From an end-to-end connectivity point of view, on the one hand, UMTS offers switched circuits toward the PSTN and ISDN, mainly to be used for voice communication; on the other hand, IP packet connectivity is provided as a pure network-layer service between a UMTS mobile station and an Internet host. Release 4 This is the first evolution step released in March 2001. It includes the GSM-EDGE Radio Network (GERAN) Iu interface, multimedia messaging, and improved security for Internet convergence; however, it still uses IPv4 protocols. This release offers additional features, but does not change the packet- and circuit-switched domain. TD-SCDMA is added to allow unpaired spectrum use with low chip rate (1.28 Mcps, 1.6-MHz carrier bandwidth). Some additional features include the following:
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• Improvement of the positioning methods for location services: cell
of origin (COO), optimized time difference of arrival (OTDOA), and advanced GPS (A-GPS)based (see Chapter 5);
• Support of location-based services in the packet-switched domain; • Security improvements in such areas as the mobile station applica-
tion execution environment (MExE) and USIM toolkit;
• UTRAN repeater; • Enhanced messaging (rich text formatting and still picture) and
multimedia attachments for multimedia messaging.
Beginning with this release, UMTS will provide IP transport for voice and data services. Multimedia will be delivered using the session initiation protocol (SIP) from the Internet Engineering Task Force (IETF), which was adopted by 3GPP. IPv6 will be used on the lower layers. All services will be merged using the same switching and transport mechanism based on the IP protocol stack. MGWs, as shown in Figure 3.23, guarantee, together with the media gateway control function (MGCF), the transition from UMTS to traditional telecommunications networks (PSTN, ISDN, PLMN). This is especially important to achieve transparency for voice services. Voice call state control functions (CSCFs) will be handled by a new network element. The VoIP server will do the transport and switching functions. A new principle called service enablers is used in the specification work for this and for all subsequent releases. They allow the following: Release 5
• The creation of new services; • The charging of data collection for these services; • The roaming users access functionality.
The 3GPP standardization groups understand this new way of standardization as a framework for all IP-based multimedia services (IMSs). As a result, the main service categories for UMTS are considered in such a way. For example, in the voice service, beginning with simple voice, each user is addressed either via the ITU E.164 scheme or the SIP URL scheme, which may include the E.164 user ID. Personalized announcements for the users own languages shall be included. The service can be upgraded later to the so-called rich-voice service with the addition of images or video.
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A number of main service categories will be specified on the basis of service enablers. The services themselves (which are under discussion for Release 5) include the following: • High-speed downlink packet access (HSDPA) of 10 Mbps; • New voice codec (AMR 16 kHz); • CAMEL Phase 4, interactions with optimal routing; • End-to-end QoS in the PS domain; • Multimedia messaging service enhancements; • Instant messaging support; • USIM toolkit enhancements; • Prepay and real-time charging; • Smart antenna and beamforming; • UTRAN for 1,800- and 1,900-MHz frequency bands. Release 6 and Beyond Additional releases are in progress. It may be assumed, however, that they will go in line with the evolution of the Internet. High-level objectives for Releases 6 and 7 are under discussion Release 6 • The specification of additional capabilities enabling greater exploita-
tion of IMS (e.g., additional naming and addressing scenarios);
• Capabilities leading to greater operational flexibility (e.g., multi-
GGSN);
• Exploitation of TDD; • Exploiting high-speed packet downlink access (HSDPA); • Introduction of WLAN. Release 7 • The use of alternative access technologies in addition to those
already specified (e.g., WLAN);
• Greater convergence with IP technology (e.g., security, IPv6 devel-
opments);
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• More efficient IMS (e.g., solutions that avoid the need for the GPRS
tunnel);
• Further radio technology improvements (e.g., HSDPA develop-
ment);
• New and enhanced APIsboth network and terminal; • New and enhanced codecs.
Similar to GSM, a typical characteristic of UMTS is the separation of transport and call control. Thus, the UMTS radio access and core network up to the GGSN element may be regarded as a mobile access network to the Internet components in the value chain (e.g., ISP, Portal). The ISP and portal functions remained untouched from the 3GPP standardization up to Release 5. However, the transition from IPv4 to IPv6 impacts these components, as soon as Release 5 is put into the radio and core networks. The combination of the circuit and packet domain results in the possibility of using a common IP backbone for switching and transport inside the network. The use of IP protocols will be extended also to the radio network down to the mobile terminal, which will finally allow end-to-end IP-based communications. Figure 3.24 shows the core network Release 5 and beyond. Subscriber Media Mobility Call-state Media management management resource control gateway function function function control function function SMF
MGCF MGCF
MRF
CSCF CSCF
VoIP MSC UTRAN UTRAN Radio radio Access access
MGCF
PSTN ISDN PLMN
ISUP
MGW
IP backbone Iu SGSN
Internet Intranet IGSN IGSN (GGSN)
Figure 3.24 Core network Release 5 and beyond.
ISP
Portal
Content
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3.2.4.1 Integration with the Internet
In the fixed Internet, when users move with their computers from one network to the other, mobile IP is used to correctly deliver the datagrams to the new location. Mobile IP is quite similar to the mobility management mechanisms of traditional cellular mobile networks, although it differs in many protocol details and address formats. Mobile IP will stepwise converge with the mobility management of the cellular mobile network. The principles of the mobile IP are as follows: 1. There is a discovery procedure, so that mobile computers or devices can determine their new access points when they are moving from one location to another. 2. There is the registration of an agent in order to represent the mobile computer or device while it is away from the home network. 3. A mechanism is required to deliver the datagrams to the mobile entity while it is away from the home network (tunneling mechanism). Addressing is one of the most important criteria in this context. IP addresses in the Internet are primarily used to identify a particular end system. IP addresses are thought of being semantically equivalent to the domain names. The transmission control protocol (TCP) operates between the communication end points and their IP addresses. These addresses are used as destination addresses for Internet-related routing. Mobile IP extends IP by allowing the mobile computer or device to utilize two IP addresses, one for identification, the other for routing. The IPv6 protocol and its attendant address configuration protocols (auto configuration) provide a valid base for mobility management. When the mobile is away from home, it registers its care-of address with its home agent. The home agent has to tunnel the datagrams that arrive at the home address to the care-of address. At the care-of address, the datagram exits from the tunnel and is delivered to the mobile computer or device. For datagrams that are sent from the mobile computer or device to a fixed Internet address, standard IP routing takes place directly to the destination. Cellular networks have a mobility management system in place that uses the HLR and the VLR for user registration using the E.164 addressing scheme. Handoff procedures are handled by the GPRS support nodes. Problems arise for datagrams from the Internet that are routed according to the destination IP address. An address translation has to take place from the IP address to the ITU E.164 address. Address allocation is established
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during the session setup, when the mobile computer or device gets a temporary IP address (care-of address) and uses this address instead of its home IP address. In addition, the home agent is informed to register in order to route the datagrams via the GPRS tunnel to the mobile computer or device. In case of the integration of the cellular mobility management with the Internet under GPRS and UMTS Releases 99 and 4, the user may select an ISP or intranet server using its ITU E.164 address and the access point name (see Figure 3.25). The user device first performs the international mobile subscriber identity (IMSI) attach and GTP context setup procedures, which establish a link layer connection to start using 3GPP services for packet data. Over this connection, the GGSN sends an agent advertisement message; the mobile device gets its care-of address and then registers with its home agent. The standards do not appear to define in detail the relationship between the GGSN and the ISP or intranet, nor the type of connection that the GGSN may require. For example, it could be argued that the GTP should be extended to the ISP or intranet or that an additional tunnel segment should be added. Equally, it is not clear whether the ISP or intranet must have a leased line connection to the GGSN or whether any ISP or intranet could be accessed over the public Internet. In Release 5 and all subsequent releases, the operation of the mobile IP could be as follows: Connection-oriented (TCP) Connectionless (UDP) Packet domain connection-oriented (access)
A Mobile user USIM Client
Internet domain connectionless IP
GTP GTP Tunnel SGSN
GPRS backbone
GGSN
ISP or Intranet PoP*
GTP IP IP End-to-end communication path *PoP = Point of presence
Figure 3.25 Communication path. (Source: UMTS Forum.)
Internet
Portal
B
Server
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1. Replacement of GPRS. GPRS protocols will be replaced by IP throughout radio access to the mobile device. Mobile IP will be fully deployed. A home network router called the home agent (HA) tunnels the datagrams to another router, either the foreign agent (FA) in the visited network or directly to the mobile host. The new location of the mobile host is made known to the HA using registration signaling. The HA and FA send periodic agent advertisements. The mobile sends a registration request to the FA, which is relayed to the HA. Registration terminates with a registration reply sent to the mobile by the FA. 2. Handoff for mobile computing. As the mobile computer or device is moving (e.g., at vehicular speed), the transitions should be as smooth as possible. This could be difficult if datagrams were dropped because the mobile just left the location area. Route optimization is a solution that could avoid the home network being involved in datagram transmissions by establishing special tunnels. 3. Authentication. In addition to the well-known out-of-band security features based on the SIM/USIM card and the GSM/UMTS authentication server, registration keys and security protocols are needed to accomplish security. 3.2.4.2 Mobility Management Towards Service Mobility
The integration of the Internet with cellular mobile networksas is taking place with UMTSpromises a distributed computing infrastructure for UC irrespective of the users location, even if it changes dynamically. This essential feature of wireless wide area mobile networking is based on the guiding principle of personalized communication. Achieving such personalization will create new service and business opportunities, thus changing the Internet dramatically. There are several forms of mobility: • User mobility requires a uniform service offering independent of the
terminal and the user location, whether it be regional, national, or global.
• Terminal mobility allows devices to transparently move and connect
to different access points in many networks. The dynamic and automatic adaptation of mobiles to the network is an important requirement, which is fulfilled to a large extent for handhelds in GSM and UMTS networks.
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• Service mobility means that users obtain services and maintain
sessions in a transparent way regardless of the point of attachment. This includes service migration and its adaptation to different terminals, interfaces, and networks.
Many proposals suggest the use of mobile agent technology to address these issues. A mobile agent moves entities in execution including code, data, and achieved state and upgrades distributed computing environments without suspending the service. GSM already provides a virtual home environment for the services as defined in GSM. Third-generation systems face numerous terminals with different capabilities and multiple services, some of which will not be offered directly to the user in all mobile networks. Thus, the concept of a user virtual home environment has to be expanded. It should comprise the mobile virtual terminal as well as a virtual resource management. The user virtual environment provides a uniform view of the users operating environment, independent from the users location and his specific terminal. The mobile virtual terminal extends the traditional terminal mobility. The virtual resource management maintains information about current location of available resources and services. It implements server-side functions, just like the mobile virtual terminal has to care about the client-side functions. Virtual resource management can be seen as the engine for the so-called service portability of UMTS, because it establishes dynamic connections between mobile terminals and the needed resources. In global scenarios, the virtual resource management has to address resource and service heterogeneity. Java and Jini, Simple Object Access Protocol (SOAP), or common object request broker architecture (CORBA) are means to perform such tasks. 3.2.5
Internet Service Providers Function
Simply stated, an Internet service provider (ISP) provides access to the Internet. The level of service an ISP provides, and the set of functions it offers to support the end user, however, vary. Like in a client-server model, the ISP provides the user@host account [point of presence (PoP)], which means that the ISP has to manage the users addresses and applications-related protocols. In the UMTS network, the ISP is also the transition point from the mobile users access protocol GTP (which is connection-oriented) to IP, which is connectionless. On top of IP is either the connection-oriented TCP or the connectionless User Datagram Protocol (UDP). In all cases of accessing the Internet via tunneling for HTTP, e-mail, FTP, or TELNET, the ISP has
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the responsibility for the end users account. As a consequence, the all-IP UMTS (Release 5) network positions the UMTS operator into the role of an Internet service provider. This network can be combined with extended functionality that supports the roaming user: mobile ISP. Additional complexity comes from interoperator roaming. UMTS is designed as a truly multiservice platform. The migration to an IP-based network will take place according to a phased approach. In the first step, a flexible tunnel solution allows access from the mobile terminal via GPRS to the ISP access point (from the ISP, the user can build a session via a portal or directly to a server. See Figure 3.25). In the second step the IP protocol set is introduced into the core network and, as the third step, into the radio network. In the first UMTS releases up to Release 5, the user selects an ISP or intranet using the access point name. Since the current Internet uses IPv4, network address translation (NAT) may be introduced in order to decouple the internal addressing (intranet) from the public addresses used (some firewalls use address translation as a security measure). UMTS Releases 3, 4, and 5 allow a choice of IP version (IPv4 or IPv6), but Release 5 multimedia services exclusively use IPv6 for the Internet domain. The basic UMTS-ISP functionality is shown in the block diagram of Figure 3.26. Organized by the IETF in 1992, the IPv6 is now an accepted standard by the IETF and vendors. The protocol resolves scalability issues by allowing DNS
Registration (user@host) All services
End user
Common access channels
Service protocol support HTTP
Internet access Intranet access (firewall) Server access
SMTP FTP TELNET SIP SMS
Figure 3.26 UMTS-ISP functionality.
WWW access Portal E-mail File transfer
Internet e-mail Intranet server Database server Chat VoIP GSM networks
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nearly every digital device to possess an IP address. Also, the nomadic nature of traditional communications is taken into account with the inclusion of mobile IP. There are different versions of the protocol, and for certain cases no compatibility is given between these two protocol sets. The new version of the protocol (IPv6) has a variety of key attributes, including an expanded addressing space of 128 bits, from 32 bits. Other key and enhanced attributes include the following: • Option mechanism: Allows router processing at much faster speeds; • Address autoconfiguration: Allows dynamic assignment of addresses; • Resource allocation: Permits priority messaging; • Security: Delivers improved authentication and privacy.
Client-Server Architecture
One of the primary objectives for UMTS is service differentiation: to allow network operators (and service providers) to market products based on more than just coverage and capacity issues. The key factor here is the ability to develop and offer new features in short timescales, without requiring modifications from infrastructure suppliers. Many new developments in the IT industry are based on a client-server technology, which allows applications to be downloaded transparently (from a server) into the users terminal (the client), providing direct and immediate high-performance user interaction, validation, and interpretation. Tasks that must remain centralized, such as maintaining databases, are held on centrally administered servers and respond to queries from the clients rapidly and efficiently. Many examples of commercially successfully client-server solutions are to be found in the banking, travel, and service industries, which have been enabled by the growth in the use of desktop PCs and low-cost networking links. For the mobile industry, intelligent terminals and USIM cards will allow personalization of the user interface and provision of features not possible with basic terminals in todays networks. With the increase in roaming traffic, the ability to provide such features independently from the serving network will become increasingly important. Existing and evolving standards, such as SIM Toolkit, Java, and the mobile execution environment, together with other initiatives, such as improved WAP (XHTML-based), provide the framework for delivering this client-server approach. The use of
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an object-oriented language like Java is attractive because it is platform- and OS-independent, which optimizes the download. 3.2.6
Mobile Portals Function
A portal provides a gateway to the desired information location. Its basic task is in information retrieval using keyword-based methods. It is related to Web services and is positioned in the value chain between the ISP function and the content or application server function (see Figure 3.27). In the i-mode service (launched by NTT DoCoMo/Japan in early 1999 is an HTML-based mobile Internet service with more than 100 search engines), it can be seen that more than 50% of all accesses to content are going via the i-mode portal, while the remaining 50% (other applications) are using uniform resource locator (URL) or IP address access. Multimedia information changes the nature of portals, which must also become multimediacapable. Information in images, audio, and video differs from that in text documents. It can be assumed that the role of a portal will change in mobile envi- ronments in the context of transaction-oriented services and applications (m-commerce). The current popularity of portals arises directly from the information explosion [36]. As a result, finding information and getting to it becomes very difficult. The definition of a portal has increasingly to do with virtual
Operator Operator services Services HTML XML
Access Access andand Transport transport
cHTML
ISP ISP
www services WWW services xHTML WML
Search Style sheet Web transformer
Subscriber policy Management billing Personal references Device characteristics Location + information + individualization
Figure 3.27 Portal positioning.
Other Other portals Portals (cascaded)) (cascaded www WWW services Services
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market and information places within the Internet and intranets and its single point of access to aggregated informationsomeplace you go through to get something else. It could be a Web supersite or a search engine that provides a variety of services like Web searching, news, white and yellow pages directories, free e-mail, discussion groups, on-line shopping, and links to other sites. It could be seen as an infostation, where a search engine works like a navigator for Web sites, but in the future also for direct-marketing and e-commerce. Trends in portal development can be classified into three major categories: 1. Content-oriented portals are either related to general content areas (horizontal portals) or to specific content areas (vertical portals). 2. End-user-oriented portals are tailored to user groups, terminal characteristics, and intranet portals. 3. Convergence-oriented portals are multiaccess portals, multidevice portals, and multilingual portals. Portals enable users to control Internet commerce; together with ISP servers, they may also control end user access and take over administration. With the move toward personalization, it is very important to optimize the search process according to the users profile and the business objectives of the portal operator. Whereas traditional portals are designed to provide a mechanism to organize information delivery to specific market segments, the mobile multimedia portal will be oriented towards individual users to reflect their needs for secure and robust access in changing locations and circumstances. Using an intelligent IP-access platform with dynamic service-selection capabilities, the portal owner can provide personalized location-dependent services that are tailored to the mobile users individual requirements and choices. This type of personalized portal allows the customer to select, subscribe to, and configure all type of services. The mobile multimedia portal operates on a higher level in the control chain, providing access to and selection of all IP-based services, including, of course, the Web. Other mobile-related services, which will be managed by the portal, come from audio and TV-media providers, ASPs, yellow pages, advertising companies, and from the portal owner itself. The portal can offer a personalized home page, which can help the portal owner to deliver valueadded services tailored to the customers personal profiles.
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The main development steps for a mobile multimedia portal are as follows: 1. A traditional portal provides the search engine and a preselected Web page catalog. 2. Then, the personalized portal takes into account user profiles and takes care of the user-owned database. 3. By delivering the users device position via the radio network, the location-based portal will search for user-location-dependent data. 4. The video portal will allow entrance to the world of movies and broadcasters. It will support access to all media relevant information from the TV and radio broadcast sector. This will be possible as soon as sufficient capacity can be provided for streaming videos. To accommodate the continuous enhancements of a phased approach, a mobile multimedia portal platform is needed and will be defined. Such a platform will include more functionality than todays portals provide. 3.2.6.1 Portal and Content
Providing the portal does not mean creating the content. Content feeds are likely to come from existing content providers or via other portals (cascaded). It naturally follows that the first applications focus on building the subscriber base. Next should come applications that drive subscriber profile data capture, such as personalized subscription-based content (style sheets) push and wireless personal information synchronization. Only after building the profile database can mobile e-commerce and advertising be successful. A main issue experienced by mobile Internet services is the provision of memory space for mobile users to create their own Web pages. The i-mode example in Japan has proven that thousands of mobile users are using the service for such purposes. To enable the mobile multimedia portal to be built and run, a platform must be prepared. UMTS, as a multiservice system, has to care about the provision of information-based services. Internet service provision is the basic function needed by the end user to get access to portal functionality and content. The protocol support needs to be determined (HTTP, SMTP, FTP). Tailored Internet-based services and multimedia service provisioning will be key service areas.
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3.2.6.2 Transforming the Mobile Portal into a Multimedia Transaction Platform
A mobile portal or UMTS portal is only the beginning of the design of a switching platform for mobile Web services that will find high market acceptance in the UMTS market. The platform building blocks can be developed in various steps. They are shown in Figure 3.28 [36]. A proposed platform with stepwise deployment is described below [36]. Basic functions include the following: • A traditional portal tailored to mobile users; • Inclusion of a WAP portal for GSM compatibility; • WML, HTML, XML, XHTML, and cHTML provisioning; • UMTS operator Web pages for its own services (advertiser) and user
Web pages;
• Access to other portals (generalized portals, voice portal, and other
mobile portals).
Building blocks User userprofile profile User userdata data (personal) (personal) location Location datadata security Security data data terminal Terminal datadata
User'suser's homepage homepage
Access accessportal portal serviceportal portal Service Searchsearch engine engine access access
Unified mail box (e-mail, SMS, voice mail, video mail)
Shoppingshopping mallgateway gateway mall
Wallet wallet Horizontal horizontalfunctions functions Billing billing
QoS control control
Interworking/ Interworking/ conversion conversion
custom Customization ization
Payment payment broker broker
Figure 3.28 Mobile multimedia transaction platform building blocks. (Source: UMTS Forum.)
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A second step should add such user-related, individual search features as the following: • Personalized portal; • User profile management; • Support of customized infotainment.
A third step could deal with user roaming and location by adding the following: • User profile management for roaming users (VHE); • Content-dependent QoS control; • Location-based services.
A fourth step could imply the following: • E-commerce that is interactive and based on end-to-end security; • Service portability (a combination of IN/CAMEL/MExE); • Content-dependent billing, transaction-based billing (e-banking),
and real-time billing; • An AV portal.
The portals function is to serve the mobile user. On the other hand, the operator has justified interest to get to business using this functionality. The end user will have some of the following expectations: • Device- and preference-specific presentation of information; • Personalized service; • Acceptable Web transformation to the devices capabilities; • QoS, security, and privacy; • A single bill.
Personalization is seen as a major point of portals. Where appropriate, based upon the users active interests (sports results, stock warnings, breaking news), intelligent agents, or data robots, are launched to get and keep looking
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for information of interest to the user. Some of this information can also be location dependent. Aggregation of information has to take into account the user profile, particularly in the case where the user has access to some specific sources. After the information is collected, filtered, and integrated, it has to be dynamically formatted taking into account the device or type of terminal involved and the available bandwidth. The display characteristics will be evaluated in the session initiation process, and the portal will adjust the information (transformation) as required. 3.2.6.3 Building a UMTS Portal Platform Architecture
A number of issues that impact the architecture of a mobile portal platform can be tailored to such factors as applications, personalizations, location dependency, voice, messaging, and the like. Open APIs are important to integrate with permanently changing environmentson the users side with the changing capabilities of the devices, and on the content side with the applications. The flexible interfacing with back end systems and external systems, such as content provider servers, will increase as services get more advanced and customer awareness increases. Transformers and adapters in the mobile portal platform have to deliver any content to any mobile device, from laptops to PDAs to handhelds. Their objective is to transform content without rewriting the application. The level of personalization and customization is key in building the platform. For location-dependent services, positioning information has to be received from the access network and processed together with personal- and application-related content. Customer policy management and billing are important functions in order to get the operators revenues. The type of gateways and other application-oriented servers are dependent on what service categories will be selected. There are five main service categories: 1. Messaging and e-mail; 2. Infotainment like news, cinema, music, video on demand, and books; 3. Directory services, such as yellow pages, and location-dependent services; 4. Voice and video support services; 5. M-commerce services like mobile banking, shopping, and trade. An example of a portal platform architecture is shown in Figure 3.29. It is efficient in that the basic architecture stores content in a generic XML
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Radio access incl. ISP
cHTML cHTML HTML HTML GWY GWY VXML VXML GWY GWY WML WML xHTML xHTML GWY GWY
Portal platform server Transaction management Transaction Mgmt. Services Services Mgmt. management Re-use existing Reuse of existing content Contenttranformer content Content tranformer
Location and and personalization Server server
XML XML Content content Server server
Directory Directory Server server Subscriber Subscriber Policy policy Serverserver personalization Personalis .
Content Content Provider server Server Internet Internet
Billing Billing Server server Website Web Site server Server
To other portals
Figure 3.29 Portal platform architecture.
format and then generates specific device-oriented output via gateway functions. Examples of output languages are HTML for standard laptops, WML for WAP devices, XHTML for i-mode devices, and VoxML for voice support. This concept makes the creation of services simple and allows compatibility in the transition from GSM/GPRS to UMTS-based services. It also allows Web service, which is created to be immediately available on all mobile devices. For roaming users, another requirement has to be fulfilled: If the roaming user accesses a mobile portal in the visited network, there is the expectation of man-machine interface (MMI) and eventually personalized support, as defined as the virtual home environment. Thus, the UMTS portal platform has to be interconnected with the visited networks portals in order to exchange the user-related data. This will also be a matter for standardization. Other standardization items include the following: • Using agreed-on and compatible hypertext (HTTP) standards
releases (XML, HTML, WML, and XHTML);
• Using agreed-on higher layer IP standards (IPv4/IPv6, SMTP); • Using other database-related standards like Java database connection
(JDBC);
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• Using JavaServer Pages (JSPs), JavaScript, WCML, XSL, and PML
for customization and personalization.
The deployment of a UMTS portal platform should follow the framework of a strategic architecture that defines the evolution of the environment (including the services offered) in a few major phases. 3.2.6.4 3G Portals Related to Main Service Categories
Portals provide Web services. Thus, 3G services that use the Web will require mobile portal support. The mobile portal can be seen either as an integral part of the 3G operators network, or as an entity that is operated by a third party. Some mobile portals can be seen as an extension of the fixed Internet and intranet portals. Mobile portals, however, are also optimized or exclusively developed for content optimization due to the small form factor mobile devices. Until now, the mobile operators usually provided the specifically developed portals for smart phones and PDAs. Portals are also often classified due to content areas as horizontal or vertical portals. Horizontal portals have a broad focus of mostly common applications, such as m-commerceexamples are Excite, AOL, and Yahoo. Corporate portals can also be included in this category. Vertical portals are focused on particular market segments like sports, smart cars, or travel. If portals are considered from a 3G services point of view, they should be structured into the six main service categories identified for 3G [42], which encompass different business models and different portals tailored to these businesses. Intranet Portals (Business User)
These are also known as enterprise portals and they are initially deployed as corporate, internal wireline Web search engines. The devices for mobile access are typically laptops, notebooks, PDAs, and also handhelds. Security is a major factor, especially if it is extended to the intranet portal for external mobile actors and for customers and subcontractors. The addressing will be managed via tunneling throughout the public mobile network. WAP-based mobile extensions of the intranet in 2G and 2.5G mobile networks are following the wireless transport layer security (WTLS) protocol to secure connections via the mobile network. In i-mode, mobile access to Intranet is secured via the secure socket layer (SSL) protocol. The Internet standard protocols SSL and TLS provide a different encryption algorithm and are therefore not compatible with WTLS; thus, conversion is required
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(gateway function). This incompatibility could also be a problem on the terminal side, if the terminal is used for mobile Internet access and WAP access as well (e.g., PDA). Of course, the browser or microbrowser has to be in line with the intranet portal standards, with the markup languages HTML, WML, or XHTML. XML is generally used within the portal platform. Internet Portals (Business User and Consumer)
Many Internet portals were deployed for wireline Internet applications and were extended for mobile access with laptops, notebooks, pocket computers, and PDAs. As already described, in 3G mobile networks, GPRS tunneling or circuit-switched access is used in order to achieve a converged solution for wireline and wireless communications. Addressing is managed via a dynamic address pool for GPRS-based tunneling where the users domain name remains the same for fixed and mobile use. The number of browsers and microbrowsers is increasing according to the markup languages used, generally HTML. Mobile Portals (Consumer-Oriented)
These portals are specifically developed for mobile devices (handhelds, PDAs)examples are the mobile portals for i-mode and WAP services. Personalization and filtering regarding the mobile terminal are main characteristics. In addition, security is fulfilled with specific standards (WTLS). On the terminal side, microbrowsers are used following the markup languages cHTML, WML, and for 2.5 and 3G XHTML. Special Portals (Business User and Consumer)
Such portal developments deal with location-based services or managing services based on the Web. In case of location-based services, personalization and position information have to be analyzed as the criteria for searching information. The services are usually related to mobile handhelds and PDAs. The use of various markup languages may lead to a multibrowser situation, if it comes to simultaneous use of services (e.g., voice XML browsers for accessing voice portals, multimedia messaging portals, HTML browsers for traditional portal access, XHTML for typical mobile specific services, CXML for m-commerce).
Technologies 3.2.7
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UMTS Terminal Technologies
Voice-only terminals will not be adequate for a UMTS environment. Even for voice-centric usage, a terminal it will have to support additional services, such as e-mail, Internet access, and software download. A low-end terminal will do this in a rather basic manner with a medium resolution display and restricted data transmission rate. At the high end we envision terminals with large and intelligent displays [43] with multimedia capability. Reconfigurable touch screens will be used to personalize the MMI, and fast multimedia services will be supported with a maximum UMTS data rate, which will depend very much on the terminals performance. In between the two ends there will be enough space to position terminals with a variety of feature levels. The transmission rate capability of the UTRA network will provide at least 144 Kbps for full mobility applications in all environments, 384 Kbps for full to limited mobility applications in the macro- and microcellular environments, and 2.048 Mbps particularly in the picocellular environments. The 810-Mbps rates may also be available for downlink short-range packet applications in microcells, depending on radio network planning and spectrum availability (e.g., HSDPA). 3.2.7.1 Multimode UMTS Terminals
UMTS terminals will exist in a world of multiple standards, and this will enable operators to offer maximum capacity and coverage to their user base by combining UTRA with 2G and probably other 3G standards. Therefore, operators will need terminals that are able to interwork with legacy infrastructures, such as GSM/DCS1800 and DECT, as well as other 2G worldwide standards, such as those based on the U.S. DAMPS standard (IS-136), because they will initially have more complete coverage than UMTS. Many UMTS terminals will therefore be multiband and multimode so that they can work with different standards, old and new. Achieving such terminals at a cost that is comparable with contemporary single-mode 2G terminals will become possible because of technological advances in semiconductor integration, radio architectures, and software radio. 3.2.7.2 GSM and UMTS Interoperability
The following three types of GSM and UMTS multisystem terminals have been defined by 3GPP: 1. Type I terminals are basically two independent GSM and UMTS terminals merged into one shell. The capabilities of type I terminals
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to perform intersystem handovers are somewhat limited since the handover basically corresponds to setting up a new call in the other system. The handover is not seamless, as the terminal has to disconnect from one system before accessing the new system. 2. The type II terminal is similar to type I, with the main improvement of being able to listen to paging information from one system while being in active mode on the other system. Hence, the type II terminal has a shorter handover period than a type I terminal. 3. The type III terminal shall be capable of being connected to both the GSM and UMTS systems simultaneously. Only the type III terminal allows a true seamless intersystem handover between UMTS and GSM. The type of terminal has a strong impact on the RF hardware implementation of the terminal. Type I and II terminals only require one RF-receiver, whereas type III terminals require parallel RF receivers, thus imposing higher costs. Seamless intersystem handover between GSM and UMTS is being carefully studied and specified by 3GPP. It should be emphasized that the 3GPP UMTS specifications are a necessary task in order to facilitate seamless GSM and UMTS intersystem handovers. Whether and how intersystem handovers between UMTS and GSM will be implemented, however, is in the end determined by the network and terminal manufacturers, the network operator, and the terminal users. 3.2.7.3 IS-136 and UMTS Interoperability
This type of terminal depends on the definition of the migration path from IS-136 to UMTS. Not only the radio interface has to be covered, but also the network standard IS-41. 3.2.7.4 Reconfigurable Terminals
UMTS terminals will have to exist in a world of multiple standardsboth second-generation standards and other members of the IMT-2000 family. Also, standards themselves are expected to evolve. In order to provide universal coverage, seamless roaming, and nonstandardized services, some of the elements of the radio interface (e.g., channel coder, modulator, transcoder) will no longer have fixed parameters; rather, they will be in the form of a toolbox whereby the key parameters can be selected or negotiated to match the requirements of the local radio channel. In addition to the capability of
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adapting to different standards as described above, downloadable terminals will enable network operators to distribute new communications software over the air in order to improve the terminals performance in the network or to fix minor problems. An example might be the downloading of an improved handover algorithm. This aspect of software download will be generally invisible to the user. 3.2.7.5 Application and Service Download
When using todays multimedia terminals (for example PCs), users have accepted the idea that the capabilities of the terminal can be modified over time through software download. It is now commonplace for a user to download a new plug-in (for example, a video or audio codec) to access new types of content. The introduction of multimedia services on UMTS will take this concept into the mobile domain. UMTS plug-ins will come from a variety of sources, such as the following: • Preinstalled on the users terminal by the network operator or service
provider; • Downloaded over the air, at the users request or automatically by the network, much as today, where many ISPs upgrade ones software or databases during a session; • Supplied on media, such as CD-ROM for example, free with magazines or direct mail. This concept of software download will be closely linked with newly developed SIM capabilities discussed above. The terminal and the SIM will cooperate in requesting, storing, and executing software plug-ins. Ideally, the majority of new software would be stored on the SIM to allow the user to SIM roam onto a new terminal while still keeping the optimum home environment. Such developments require such major changes in the design of 3G terminals as the following: • Architecture: New OSs are needed; • Power consumption: Todays mobile devices are the benchmark; • User interfaces: The MMI has to be multiservice-oriented and cannot
directly be derived from PCs; • Technologies: Flat-screen technologies with full color and touch are needed.
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A few examples for multiservice functions in 3G mobiles are WML, HTML, XHTML browser, other browsers, Java, low-rate video, still picture, FM radio, MP3, MPEG-4, SIP/video conference, e-commerce support, security and identification, integrated Bluetooth software environment for local download, Internet and intranet access, and location identification.
3.2.8
USIM Cards and Smart Cards
A major step forward in mobile networks was the introduction of the subscriber identity module, which uses generic smart-card technology. It provided the possibility of high security and a degree of user customization to the mobile terminal. SIM requirements, security algorithms, and card and silicon integrated-circuit (IC) technology will continue to evolve up to and during the period of UMTS deployment. It is remarkable that in October 1999 exchangeability of SIMs in UMTS and GSM was chosen. As a result, it is required to be able to personalize both GSM-only terminals and dual-mode UMTS/GSM terminals using a USIM in order to be served in a 2G GSM-only environment. Conversely, it may be possible to insert a GSM SIM into a UMTS terminal and access a UMTS system. To ensure dual-mode UMTS/GSM operation, backward compatibility has to be maintained with earlier phases of GSM. By 2002, the smart-card industry will be able to offer cards with greater memory capacity, faster CPU performance, contactless operation, and greater capability for encryption. These advances will allow the USIM to add to the UMTS service package by providing portable high-security data storage and transmission for users. Not only configuration software for the operation of any UMTS terminal, but images, signatures, personal files, fingerprint or other biometric data could be stored, down- or uploaded to or from the card. Contactless cards will permit much easier use than todays cardsfor example, this would allow the smart card to be used for financial transactions and management, such as electronic commerce or electronic ticketing without having to be removed from a wallet or phone. It is expected that all fixed and mobile networks will adopt the same or compatible lower layer standards for their subscriber identity cards to enable USIM roaming on all networks and universal user access to all services. Electronic commerce and banking using smart cards will soon become widespread, and users will expect and be able to use the same cards on any terminal over any network.
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New memory technologies can be expected to increase card memory sizes making larger programs and more data storage feasible. Several applications and service providers could be accommodated on one card. In theory, the user could decide which applications and services he wants on the card, much as he does for his computers hard disk. These are some of the challenges and opportunities for service industries that evolving smart-card technologies present. Figure 3.30 shows a few examples of 3G multimedia devices.
3.3 UC Appliances (Devices) Small information appliances, more generally called devices (or personal devices), denote a new kind of relatively low-cost computer or hardware unit designed for specific tasks like Internet access and specialized personal and business uses (e.g., personal information management), but without the full capabilities of todays personal computers and software. They are easy-to-use personal computing devices. Some offer wireless connectivity or are connected by a ubiquitous wireless network, and sometimes they will be embedded in everyday appliances in offices or homes. All small information appliances (devices) for UC have the following qualities in common:
Capability Laptop
Multimedia
Pocket PC Tablets S35
Voice Mobile phone
PDA organizer Handheld smart phone
Markup languages and operating systems HTML, XML, PML, WML, cHTML, xHTML, Windows, Linux Proprietary, EPOC, Windows CE
Figure 3.30 3G multimedia devices.
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• They are portable or even wearable. • They are easy to use, require low maintenance, and yet are sophisti-
cated devices optimized for a specific range of applications or a small number of special functions for single users.
• They are mobile or they enable some form of mobility. • They have some computing power or at least some logic. • They allow access to some kind of information and store some data
(personal data, hardware data) in an encrypted form. Therefore, they can be used for personal and hardware identification, authentication, and object-specific instructions. This is why applications with highly increased security, privacy, and availability most commonly take stage, as the data stays with its owner, not in the network.
• Some devices have wireless communication abilities. • Some devices are location-aware or they can be used for location-
aware computing.
Their major benefit is clearly that they extend the reach of information to anyplace, anywhere, and anytime. More intelligent devices may act as intelligent personal agents and present the right information at the right time. New Device Evolution
Is the first decade in the new century the decade of device convergence? Will there be an all-around mobile computing device of the future? We believe the answer to be no. Although last decades developments were followed by the convergence of devices in specific areas of entertainment, business, and communications, we now see a change, which is characterized rather by device divergence than by convergence. New developments will include the following: • Notebooks that provide full compatibility with the desktop in the
office or at home;
• Handheld computing devices, mobile phones, and Walkman
amalgamates;
• The migration of PDAs and pocket computers to multimedia
enginesthe new generation will combine mobile telephony, short
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messaging, Web surfing, and data communications with mobile Internet radio and games; • The emergence of Web pads, tablets with different LCD sizes with
an on-screen keyboard and pen;
• The migration of the MP3 layer into a mobile phone (this was real-
ized by Siemens SL45 in 2001);
• Improvements in mobile phones capability as it takes on the role of
a play devicethe Swedish company Picofon developed the action game Fight Area where mobile users can play with each other over the mobile network;
• The emergence of many built-in solutions in the car industry, as well
as for the household, and for public traffic;
• The increasing role of smart cards, tags, and iButtons for identifica-
tion and storage of personal information;
• Improved digital camera and video recorder organization.
This trend seems to follow the stream of independence from physical interfaces, different networks, and technologies. Even though this type of universality is not feasible today, the physical integration of desired functional entities into one device is taking place, which indicates feasible steps towards higher integration for a certain application segment. UC means to a large extent the invisible computer as an entity that can appear in every device and that fulfills different tasks depending on its functional assignment to a feature or an application. UC does not mean that one computing entity can do everythingit just means that computing devices will be task-specific but communicate with other task-oriented computing entities via networking. These devices are described regarding their major characteristics and the benefits that seem most valuable. Devices with relevance to UMTS are described in more detail. Sections 3.3.1 through 3.3.3 begin with card technologies as the essential basic systems for fixed and mobile identification and security, and then continue with iButtons, tags, and smart keys. Section 3.3.4 deals with mobile handhelds for 3G use. 3.3.1
Card Technologies
Much important information can be stored on card technologies. The term card technologies refers to any technology that can be placed on a card. Typically, we think of our credit or bank card, but there are other sizes and
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materials used for different applications. The card can be made of plastic (polyester, PVC, or some other material) or paper, card, or even some amalgamation of materials. The common point is that the card is a personal user device that provides its user with access to something (private data, secured locations) and it includes a form of automatic identification and data capture (AIDC) technology. All card technologies clearly identify an individual user and, depending on the used technology, grant access to places, information, or computing power. The current main card technologies are shown in Table 3.12 [44, 45]. These are magnetic stripe cards, smart cards, and memory cards (IC and optical), which will be treated as a subclass of smart cards. Other technologies can be put on cards as well (such as bar codes and touch memory), as well as combinations of them (so-called hybrid cards). Often the card will have printing on it, which may involve technologies, such as dye diffusion thermal transfer (D2T2), direct to card printing. The plastic card itself is determined by an international standard, ISO 7810: It defines the physical, electrical, and protocol characteristics, such as material, size, temperature tolerance and flexibility, the position of the electrical contacts and their functions, and the interface to the integrated circuit. 3.3.1.1 Magnetic Stripe Cards
With the advent of newer, more secure technologies, some people have predicted an end to the magnetic stripe. However, given the low cost and immense investment in the current infrastructure, magnetic stripe will not disappear any time soon. Todays hot areas are in the stored value arena. Table 3.12 Card Technologies Maximum Processing Data Capacity Power
Cost of Card
Cost of Reader and Connection
Magnetic stripe cards
140 bytes
None
$0.200.75
$750
Integrated-circuit memory cards
1 KB
None
$12.50
$500
Integrated-circuit processor cards
8 KB
8-bit cpu, moving $715 to 16- and 32-bit
$500
Optical memory cards
4.9 MB
None
$3,500 $4,000
$712
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Phone, transit, amusement, vending machine, and welfare disbursement are rapidly growing magnetic stripe card applications. Magnetic stripe cards are plastic cards with a magnetic stripe, on which user data can be stored. This is mainly used for user identification. The cards data is protected by a personal identification number (PIN). Today, magnetic stripe technology is everywhere. Cards with magnetic stripes on them are used every day without people even thinking about it (this actually makes this technology already ubiquitous). The technology has been with us for many years, but there are still many new things going on in the industry. The first use of magnetic stripes on cards was in the early 1960s. London Transit Authority installed a magnetic stripe system in the London Underground. By the late 1960s the Bay Area Rapid Transit (BART) in the United States had installed a paper-based ticket the same size as the credit cards we use today. This system used a stored value on the magnetic stripe, which was read and rewritten every time the card was used. Credit cards were first issued in 1951, but it was not until the establishment of standards in 1970 that the magnetic stripe became a factor in the use of the cards. Today, financial cards all follow the ISO standards to ensure read reliability worldwide and along with transit cards constitute the largest number of magnetic stripe cards. As stated above, due to the investment in the current infrastructure, magnetic stripe cards will not be replaced any time soon. Magnetic stripe technology provides the ideal solution to many aspects of our life. It is very inexpensive and readily adaptable to many functions. The standardization of high compulsion for the financial markets has provided the industry with a new lease on life. This, coupled with the security techniques now available, means that many applications can expect to be using magnetic stripe technology for the next 10 to 20 years [46]. The following is a list of magnetic stripe key attributes and limitations: • Well-established read-write technology; • Low storage capability; • Low-cost data carrier media and supporting hardware; • Range of security developments, to suit a range of application-
specific needs; • Reasonably durable materials, particularly for card-based products; • Contact read equipment, generally requiring a card-based carrier form.
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Common Applications of the Magnetic Stripe
The best-known applications of the magnetic stripe are for financial cards, transit tickets, and ID cards. Financial cards include the familiar bank credit and debit cards used in automated teller machines (ATMs) and point-of-sale terminals, as well as prepaid cards used in telephones and vending machines. Transit tickets run the gamut from subways, railroads, buses, to toll roads and airlines. ID cards include driver licenses, employee ID badges, membership cards, and door keys. 3.3.1.2 Smart Cards
The smart-card future is extremely bright. Many changes are happening in the electronics world today that will increase the capabilities of the technology. As the state of the art in manufacturing integrated circuits improves, smaller ICs that run on lower voltages, with less power requirements and the ability to include more memory of processing power will be produced. An increase in the speed that a card can be addressed is needed as well. Currently, the initialization of a smart card can take several seconds and even a single transaction may take longer than is tolerable under some circumstances. The following is a list of smart-card key attributes and limitations: • Growth area of AIDC technologies; • Growing and fairly substantial support base for applications; • Read-write and processing technology; • Contact or close proximity (contactless cards) read capability; • Medium to reasonably high data storage capabilities; • Relatively low-cost cards and read technology; • Enhanced security capabilities over other card-based technologies,
offering selective access to data and areas of read-only data. Encryption is used to further enhance security; transaction details and scheme encryption keys are stored safely;
• Open standards (smart cards for mobile phones are standardized
under GSM and UMTS);
• Global interoperability due to generic standards.
Smart cards are not new: The first patent was filed in France in 1974 and the first cards were used in France in 1982. The technology was rapidly accepted in Europe because the high cost of telecommunications made
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on-line verification of transactions very expensive. The smart card provided the mechanism to move that verification off-line, reducing the cost without sacrificing any of the security. In the United States, telecommunication costs have always been low compared to other countries. This means that the impetus to implement smart cards has taken longer to reach the momentum needed. The possible benefits of the acceptance of smart-card technology depend on the application in use. As there is a microprocessor on the card, various methods can be used to prevent access to the information on the card to provide a secure environment. This security has been touted as the main reason that smart cards will replace other card technologies. There are many smart cards in use today throughout the world. In 1993 approximately 330 million cards were produced by the major manufacturers. Of this number, only about 12% were true smart cards; the rest were simple memory cards. These numbers have grown quickly. Today, more than a billion smart cards are in use. Study forecasts show a $26.5 billion market for recharging smart cards by 2005. Compaq [47] and HewlettPackard [48] are reportedly working on keyboards that include smart-card slots that can be read like bank credit cards. The current hardware for making the cards and the devices that can read them is made principally by Bull [49], Gemplus [50], Giesecke & Devrient [51], and Schlumberger [52]. The more we rely on Internet technologysuch as the Web, e-mail, and Internet telephonythe more dependent we are on having some means of making our communications secure and authenticated. At the same time, mobility is gaining in importance. General network-centric applications, where resources are located throughout the Internet and access to them is possible from any location, require authenticated access and secured transactions. As a result, we need technology that will provide security without limiting mobility. Smart cards represent an ideal solution: They are small and easy to carry around, yet have enough processing power and data storage to store user profiles, encrypt and decrypt data, and support electronic commerce applications [53]. Europe accounts for 60% of the world market, which will rise to 2.06 billion shipments in 2006, according to the market research from Frost & Sullivan (March 2001 forecast). By 1999 the mobile phone card market led the applications field with shipments of about 400 million cards. Java Cards are growing fast: 80 million cards were sold in 2000, rising to about 15% of the total market. The emergence of Java platforms and Windows for Java Cards is a real boom for the industry and is redefining the smart card.
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A smart card is a card that is embedded with either a microprocessor and a memory chip or only a memory chip with nonprogrammable logic. The microprocessor card can add, delete, and otherwise manipulate information on the card, while a memory-chip card (for example, prepaid phone cards) can only undertake a predefined operation. Examples of smart cards are shown in Table 3.13. Smart cards are able to store a much greater amount of information than magnetic stripe cards and thus can carry all necessary functions and information on the card itself. Therefore, they do not require access to remote databases at the time of the transaction. The microprocessor-controlled smart card is the smallest portable computer available today. It comprises the CPU and three memory types [readTable 3.13 Comparative Survey of Smart-Card Technologies Category
System Example
Description
E-payment systems Mondex (MasterCard International) partnered with financial companies Common Electronic Purse (CEPS) Proton (Prisma)
E-cash system for micro payment. Loaded with real money via cash pointoff-line global standard, accepted by Visa, Europay International. Smart-card platform used in 20 countries (Amexco).
Network-based systems
MExE (ETSI) Ialda/EHTP (HP, Ericsson)
Platform used in GSM/UMTS networks, Java- and WAP-based. Payment system for fixed/mobile network use.
E-payment cards
Visa Cash Europay International Europay MasterCard Visa Proton 33 M ISO 7816 ISO 14443/contactless
Plastic card with microchip; works in card readers; accepted by 9,000 banks. American Express/Java card.
Mobile wallet cards
Open platform chip-card acc. to Electronic commerce modeling language (ECML)
Nokia, Nordea, Visa International created the Electronic Mobile Payment Services Project in Helsinki.
User ID/security cards
SIM cards (GSM 11.x) USIM cards (3G TS21.x, 3G TS31.x, UICC 3GTS 31.101)
Schlumberger, Giesecke & Devrient and others offer smart cards for mobile network use, Java-based, micro payment, security debit cards.
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only memory (ROM), electronically erasable, programmable read-only memory (EEPROM), and random-access memory (RAM)]. Users can safely carry their personal information with them, in an encrypted and secure form. Its major use is clearly the secure storage of private information, but private calculations, computations, and authentication are even more important. Privacy encryption calculations use the users private keys, which are never to be made public. The calculations have to be computed securely detached from any listening partners. Smart cards, with their tremendous security features, allow this, and as a result will be the key to e-commerce. The inherent risks of e-commerce are unsecured on-line transactions, but smart cards will establish confidence and trust. Smart-card features include the following: • Multiple applications on a single card. New applications can be down-
loaded and modified after issuance [e.g., universal IC card (UICC)].
• Reliable security. Although consumers want multiple applications on
a single card, they have concerns about fraud and privacy. Encryption technology and Java Card offer high security and bolster consumer acceptance by increasing their confidence in smart cards.
• Open architecture. This not only facilitates the development of
new applications, it also allows interoperability between a variety of smart cards and readers. Both benefits can spur merchant acceptance.
• Scaleable modular design. It will be easy to upgrade and extend the
life of a system, as the smart-card solution is flexible enough to be adapted in response to evolving consumer demands.
Overall, the smart card is a cost-effective storage and computing medium that provides high security and portability. Todays most popular smart-card technology is the smart card for cellular mobile phones and the telephone debit card in Europe. Smart cards enable most forms of electronic (cash) payments, like on-line banking transactions, cybercash, and enhanced financial services (secure transactions) like electronic ticketing. Another popular use is secure access control to buildings, computers, and corporate networks, and to establish identity when logging onto an Internet access provider or an on-line bank (including the security encryption calculations performed on the card). IC smart cards are also used in vending machines, in lotteries, for multiple application student ID cards, to scramble pay television signals from satellite or cable, in health-care applications, and to store
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automobile service histories. Figure 3.31 shows the possible uses of smart cards for cellular applications. In the future, smart cards will perform multiple tasks for their owners, such as the following: • Electronic identification and personal information storage (e.g., for
ID cards, drivers licenses, accessing services, and health care);
• Providing physical access to locations; • Providing access to networks, such as company networks, mobile
communication networks, information networks, and banking;
• Providing access to services; • Enabling e-commerce (electronic cash and secure financial transac-
tions), including pay phones, parking, ticketless airline travel, rail travel, and car rentals [54];
• Enabling mobile electronic commerce through mobile phones (mo-
bile micropayment, mobile e-cash, and mobile secure transactions). Drivers license
ID card
Debit card
Credit card
Health care USIM UICC CARD
Fiscal ID
Other
etc.
... and many other services will be available to cellular customers Figure 3.31 Examples of smart cards in cellular applications.
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Smart cards can also be used in both contacted and contactless applications to speed up consumer transactions and allow for additional applications on a single card. Furthermore, different card technologies can be combined on a single card. The smart cards of the future may even stop resembling cards, as smart-card technology is embedded into rings, watches, badges, and other items, making it remarkably convenient for the following entities: • Businesses. Smart cards also provide more efficient methods of pay-
ment, allow access to critical target market data, and enable new distribution channels, such as the Internet and mobile communication networks.
• Corporate, government, and university campuses. Smart-card systems
can control access to buildings and computer networks, while providing additional services and convenience to employees and students, such as vending and cafeteria payments.
• Transit operators. A smart-card solution can reduce the costs of pro-
ducing, distributing, collecting, and managing fare media; it could also increase passenger throughput while cutting equipment maintenance costs, and provide a wealth of passenger data that can be used to optimize routes and schedules.
• Government agencies. A smart-card solution can significantly cut
costs by reducing paperwork, verifying benefits, reducing fraud, and streamlining access to government programs and services.
• The health-care industry. Smart-card systems make medical records
and insurance information paperless and portable, which can translate into more effective delivery of medical services.
Java Smart Cards
Because Java Cards enable secure and chip-independent execution of different applications, the Java Smart Card allows truly personalized smart cards, where the cardholder can choose which applications to load on the card and change the applications depending on individual circumstances. Java Cards represent 15% of the total smart-card world market. Table 3.14 details several Java Smart Card technologies.
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Product Name
Special Features
Gemplus
GemXPresso
32-bit RISC processor
Schlumberger
Cyberflex
Bull
Odyssey
10-MHz Frequency
Giesecke & Devrient
Cappucino
16-bit processor
Java Smart Cards enable for the first time the implementation of intelligent agents in smart cards for mobile phones. An intelligent agent is a subset or compilation of computer code that is designed to support a specific function or set of functions. When the code module is launched, it can be routed to a host or card-resident application where it is validated to serve its designated purpose. For example, a code module might be used by a service provider to allow a subscriber to search remotely for the telephone numbers of specific services, such as plumbers or lawyers. The user might then go offline to make calls to other parties. The intelligent agent would trigger a search for the required information and, when available, would take the data and send it to the subscribers telephone smart card. Effectively, the addition of Java modules, known as applets and cardlets, enable a smart card to support all the capabilities of a stand-alone computer running a specific application program. With the integration of a fingerprint sensor, the entering of a password will become obsolete. Integrated circuit microprocessor cards (also generally referred to by the industry as chip cards) offer greater memory storage and security of data than a traditional magnetic stripe card. Chip cards also can process data on the card. They have the equivalent processing power of the original IBM-XT computer, albeit with slightly less memory capacity. These cards are used for a variety of applications, especially those that have cryptography built in, which requires manipulation of large numbers. Thus, chip cards have been the main platform for cards that hold a secure digital identity. Some examples of these cards include the following: • Cards that hold money (stored value cards, prepaid cards); • Cards that hold money equivalents (affinity cards); • Cards that provide secure access to a network;
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• Cards that secure cellular phones from fraud; • Cards that allow set-top boxes on televisions to remain secure from
piracy.
Microprocessor cards now actually have the ability to make decisions about the data stored on the card. The card is not dependent on the unit it is plugged into to make the application work. A smart purse or multiuse card is possible with this technology, which will support multiple applications. Those cards can be updated to add new applications after they are issued. The microprocessor type smart card comes in two types: a contact version and a contactless version. A contact integrated circuit microprocessor card (contact smart card) requires insertion into a smart-card reader with a direct connection to a conductive micromodule on the surface of the card (typically gold plated). It is via these physical contact points that transmission of commands, data, and card status takes place. Prior to embedding, a cavity is formed or milled into the plastic card. Then, either a cold or hot glue process bonds the micromodule to the card. Figure 3.32 shows a contact micromodule that is embedded into a plastic substrate. A contactless integrated circuit microprocessor card (contactless smart card) does not have the gold plated contacts visible on the card. It uses an RF backscatter technology to pass data between the card and the reader without
Wire bond
Epoxy
Integrated circuit
Contact pad Micromodule side view Micromodule top view Figure 3.32 Smart-card micromodule: (a) top view, and (b) side view [55].
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any physical contact being made. Both the reader and the card have antennas. Most contactless cards derive the internal chip power source from the readers electromagnetic signal. As such, it requires only close proximity to the reader, which is typically 2 to 3 in for non-battery-powered cards; this is ideal for applications, such as mass transit, that require very fast card interface. Figure 3.33 shows the top and bottom card layers, which sandwich the antenna/chip module. The antenna is typically 3 to 5 turns of very thin wire (or conductive ink), connected to the contactless chip. The advantages of this contactless system are that there are no contacts to wear out and there is no chance of an electric shock coming through the contacts and destroying the integrated circuit. In addition, users know that the components are completely embedded in the plastic with no external connections. There are, however, some limitations to these cards, which are used most commonly in applications where speed is important, like in highway tollbooths and for mass transit. 3.3.1.3 Memory Cards IC Memory Cards
IC memory cards can hold more than 4, 8, or 16 MB (e.g., Infineon Flashcards), but they have no processor on the card with which to manipulate that
Contactless chip Antenna
Figure 3.33 Contactless smart card [55].
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data. Thus, they are dependent on the card reader for processing and are suitable for uses where the card performs a fixed operation. Memory cards represent the bulk of the smart cards sold, primarily for prepaid, disposable-card applications like prepaid phone cards. Memory cards are popular as high-security alternatives to magnetic stripe cards. Examples of this might include stored value cards where the memory stores a dollar value that the user can spend in a variety of transactions. Examples might be pay phones, retail, or vending machines. Another example is the memory that is plugged into a personal computer (multimedia card). Optical Memory Cards
Optical memory cards use a technology similar to the one used for music CDs or CD-ROMs. A panel of the gold-colored laser-sensitive material is laminated on the card and is used to store the information. The material is comprised of several layers that react when a laser light is directed at them. The laser burns a tiny hole (2.25 microns in diameter) in the material, which can then be sensed by a low-power laser during the read cycle. The presence or absence of the burn spot indicates a 1 or a 0. The material is actually burned during the write cycle, so the medium is write-once-read-many (WORM) times and the data is nonvolatile (not lost when power is removed). The optical card can currently store between 4 and 6.6 MB of data, which allows the storage of graphical images, such as photographs, logos, fingerprints, and X rays. The data is encoded in a linear x-y format, and ISO/IEC 11693 and 11694 standards cover the details. Today, these cards have no processor in them (although this will not always be the case). These cards are comparable in price to chip cards, but the card readers use nonstandard protocols and are expensive. The cards are currently being used to store prenatal-care records, medical images, and personal medical records, as well as for high-security drivers licenses and access and entry cards, auto repair and warranty records, secure bank debit cards, immigrant ID cards, and automated cargo. Dye diffusion thermal transfer is a digital printing technology that is experiencing rapid growth in the card sector because of its ability to render high-quality, on-demand color photographic images for high-definition fine print and IR scannable bar codes. This technology incorporates a varnish that is used to help protect the fragile images. For frequently used cards, a thin protective film is laminated over the image. The laminating film frequently carries optically variable inks, holograms, and other fraud-deterring devices.
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Currently dye diffusion thermal transfer is considered a high-end card ID technology. Given the widespread use of cheaper film-based ID systems, it will not supplant the competition any time soon. However, dye diffusion thermal transfer has one critical advantage over film-based systems in that digital images and signatures can be electronically stored and/or transmitted. This characteristic makes it one technology of choice for motor vehicle IDs and any card application that involves archiving and communication of personal identification data. [56] Dye diffusion thermal transfer is used in a wide range of applications, for example, in post card printers, and video and computer graphics printers where the precision and quality of the image are prime considerations. The technology is being used increasingly for photo ID card applications. Internationally, dye diffusion thermal transfer is being used in combination with data capture technologies, such as bar code, smart card, and magnetic stripe for national ID cards in China and Southeast Asia. [57] 3.3.2
The iButton
Applications for the iButton [58] are shown in Figure 3.34. iButton is a registered trademark of Dallas Semiconductor. Apart from its form factor, the iButton of Dallas Semiconductor [59] is basically the same as a contact Java integrated circuit microprocessor card (a contact Java Smart Card). In an iButton, the Java chip does not reside in a plastic card but in a little steel can (see Figure 3.35). This form makes it physically safe (i.e., very rugged), and allows for a different way of carrying or wearing it. For example, the iButton can be worn on a key fob or badge, and basically anything that accepts a little steel button, like in jewelry. The iButton is a computer chip armored in a stainless steel can. Like with a smart card, up-to-date and user-specific information can travel with a person or object. Unlike a smart card, the steel button is rugged enough to withstand harsh outdoor environments; it is durable enough for a person to wear everyday on a digital accessory like a ring, key fob, wallet, watch, metal card, or badge. iButton key features are described as follows: • Sturdier than a card and wearable on a key chain, ring or belt, the
iButton adapts well to diverse cultures, climates, and currencies. The iButtons ability to keep digital change handy beats fishing around in a pocket or purse.
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E-stamp
Clothing
Wallet Agricultural application
Java-powered ring
Figure 3.34 iButton.
Approximately 18 mm
iButton chip Approximately 6 mm Figure 3.35 Java-powered iButton.
Glass lens
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• The technology could be programmed and set up. • The user must supply a PIN before the iButton wallet will dispense
any cash, which uniquely protects the user. Since the password incorporates the iButtons unique 64-bit serial number, it is guaranteed to be unique.
• Data passing to and from the iButton is encrypted, which protects
both the vendor and the wallet user from third-party interference during a transaction.
• It is practically indestructible and infallibly touch-connects to its
reader over many yearsno need to reinvest in hardware.
As the iButton and its receptor are both impervious to rain, cold, snow, dirt, EM fields, and hazardous chemicals, as well as being unbreakable and tamper-proof, maintenance needs are minimal, if at all. Like smart cards, multiple different iButtons are available: The major groups are memory iButtons (Section 3.3.2.1) and Java-powered cryptographic iButtons (Section 3.3.2.2). All iButtons, however, have a guaranteed-unique, unalterable 48-bit registration number engraved both on the silicon chip and on the steel lid of the button. This can be used for a basic security scheme to identify people, objects, or locations. 3.3.2.1 Memory iButtons
Memory iButtons have various amounts of memory for storing text or digitized photos. The data can be updated as often as needed with a quick, momentary contact. They vary in memory type, size, and additional special features. Memory-Only iButtons
The simplest memory iButton has only 64 bits of memory and stores its serial number and group identification. With this electronic credential secured in hardy stainless steel, this iButton serves in personnel ID systems, access control, equipment tracking, route logistics, quality control, and other automatic data logging applications. All iButtons have this feature. Other memory iButtons store more data (up to 64 Kb read-write nonvolatile memory) in different formats (of memory pages), with communication speeds up to 142 Kbps and password protection to secure memory pages inside the chip. They allow the association of a database with a person or object. With the right accessory, such as plastic key fobs, photo ID badges,
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mounts, and retainers, they can be easily mounted on printed circuit boards, machinery, or containers, or be carried or worn by people. Removal for reprogramming and reuse is equally feasible. Applications include work-inprogress tracking, time and attendance, storage of calibration constants in environmental controls and manufacturing equipment, and access control. Access control can be physical or virtual, covering another broad range of applications, such as the following: • Protecting intellectual property, such as licensed software; • Guarding sensitive financial or personnel files; • Restricting access to buildings, cash drawers, or maintenance areas. Special-Feature iButtons
Some memory iButtons have a real-time clock and calendar to track the number of hours a system is turned on for maintenance and warranty purposes. With such features as interval timer, cycle counter, and programmable alarms, they can serve a host of timed access applications: As an expiration controller, the [iButton with real-time clock] can limit access of any system (for example, a car ignition) to a predetermined time period. It can be used to control the rental or leasing of software independently of the host PC. The programmer has only to set an expiration date that shuts off access to the internal SRAM and clock, and therefore access to any protected systems. An interval timer can be set to accumulate and measure sessions when power is applied, or a programmable cycle counter can accumulate on-off cycles. The user can program alarms to generate interrupts according to set times, intervals or cycle counts. Meanwhile a write-protect feature prevents unauthorized tampering with the clock and counters, making the [iButton] a guardian suitable for high-end security systems. [60]
Some memory iButtons have a temperature sensor for applications where spoilage is a concern, such as food transport (DS1921 Thermochron iButton): [Those] temperature iButtons contain a digital thermometer that measures temperatures from −55°C to +100°C and [additionally] an EEPROM that can be used either to output alarm triggers or for storing user data. Armored in an iButton, the … thermometer can measure temperatures in demanding environments…. Many sensors placed at
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different sites can report to a single port on a processor. Multidropped [iButtons] make the lowest-power temperature sensing network available inside buildings, equipment or machinery and in process monitoring and control. [60]
Some memory iButtons have a transaction counter that allows the iButton to be used as a small change purse (monetary iButton): Up to four independent change purses can be randomly accessed from the on-chip directory. On-chip tamper-detect bits report unauthorized refilling of the purses, and the cyclic redundancy check (CRC) generator provides integrity check for all data transfers. Each write cycle (Monetary Transaction) generates a unique number to audit the dispensing and refilling of the purses. The chip performs decrement transactions with less than 100 ms touch dwell time for rapid processing in crowded public facilities. As an electronic purse and transaction counter, the [iButton] has been put to work as the system of exchange and auditing control for vending machines, public transportation systems, and amusement parks. Beyond money, [it] can carry encrypted data used in high-security access control or in other applications requiring tamper-proof data transport. [60] 3.3.2.2 Cryptographic iButtons
A microprocessor and high-speed arithmetic accelerator generate the large numbers needed to encrypt and decrypt information. The Java-powered iButton adds its cryptographic circuitry to a Java virtual machine (JVM) that is Java Card 2.0compliant, enabling Java programmers to get an application up and running quickly. Like the Java Smart Card, one of the Java-powered iButtons features is its capacity to interact with Internet applications to support strong remote authentication and remotely authorized financial transactions. Messages sent over the Internet are scrambled and can only be unscrambled at the other end by someone with an authorized iButton. By establishing a means to transmit and protect user identity, the iButton becomes the users digital credential. The two fundamental problems of Internet transactions of sensitive information are authentication and secure transmission. Like the Java Smart Card, the cryptographic iButton is a very personal computer that provides for secure end-to-end Internet transactionsincluding granting conditional access to Web pages, signing documents, encrypting sensitive files, securing e-mail, and conducting financial transactions safelyeven if the client computer, software, and communication links are not trustworthy. When
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PC software and hardware are hacked, information remains safe in the physically secure iButton [or smart card] chip [61]. Cryptographic iButtons and Smart CardsCommon Things
Both the cryptographic iButton and the Java integrated circuit microprocessor smart card have a microprocessor running a Java virtual machine (JVM). Neither has its own power supply and so each requires contact for communication (contactless smart cards are much less common). Entering a smart card into a reader or pressing an iButton into a reader (called a Blue Dot receptor) allows one to do the following: • Be granted access privileges to sensitive information on a condition-
ally accessed Web page using challenge and response authentication;
• Sign documents so the recipient can be certain of their origin (e.g.,
expense reports can be written and signed, and newspaper stories can be authored, signed at home, and sent by e-mail to the publisher);
• Encrypt and decrypt messages, securing e-mail for intended eyes
only;
• Conduct hassle-free monetary transactionsprint electronic post-
age stamps (beta tests are underway at the U.S. Postal Service) or print, write, and sign electronic checks.
An iButton with a PIN code offers the same two-factor security scheme (bring something, know something) used by smart cards and ATMs to dispense cash. Cryptographic iButtons and Smart CardsDifferences
First of all, the iButtons steel case makes it far more rugged than a smart card, and less fragile, especially when it comes to lots of memory. Additional memory on a smart card means more fragile material underneath or on the surface, which is dangerous and open to damage. More memory in an iButton means a larger size, at worst. Second, cryptographic iButtons can have more computing power than smart cards: In addition to the microprocessor, iButtons have a 1,024-bit math accelerator that performs public key cryptography in less than a second. Also, Java cryptographic iButtons have lager stacks: with 6 KB of existing RAM and the potential to expand to as much as 128 KB, the iButton can execute Java with a relatively large Java stack situated in RAM. Integrated
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circuit smart cards have a maximum capacity of currently around 8 KBa factor of 16. Third, what makes the iButton more secure than a smart card is the fact that it is worn on a closely guarded accessory. That is the whole idea of the iButton, to wear the credential on a carefully guarded accessory. The iButton can be worn on a ring (also known as the JavaRing), a key chain, a badge, a wallet, a watchanything people have spent their entire life practicing how not to lose. The iButton was made to stand up to the hard knocks of everyday wear. It cannot be bent, and it withstands pressure, temperature, water, and so on. The sturdy button signet has been wear-tested for 10-year durability and 1 million hot contacts to a Blue Dot Reader. While cards are fine for playing poker, theyre not a safe place to keep a fragile chip that defines [ones] digital identity [61]. The National Institute of Standards (NIST) and the Canadian Security Establishment (CSE) have validated a version of the cryptographic iButton for protection of sensitive, unclassified information. FIPS 140-1 validation assures government agencies that the products provide a trusted, physically secure module to properly protect secure information. The SRAM included on the monolithic chip has been specially designed so that it will rapidly erase its contents as a tamper response to an intrusion. Rapid erasing of the SRAM memory is known as zeroization. Any attempts to uncover the private keys within the SRAM are thwarted because attackers have to both penetrate the iButtons barriers and read its contents in less than the time it takes to erase its private keys. Specific intrusions that result in zeroization include the following: • Opening the case; • Removing the chips metallurgically bonded substrate barricade; • Microprobing the chip; • Subjecting the chip to temperature extremes.
In addition, if excessive voltage is encountered, the sole I/O pin is designed to fuse and render the chip inoperable. As an additional security measure, the cryptographic iButton contains a true time clock, which is a tamper-evident real-time clock. True time differs from real time in that it is set by a reputable agent and its time cannot be reset and is forever increasing. This clock can be used to time stamp transactions. It can also be used to
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impose expiration dates for inspection intervals, whereby the iButton is required to periodically check in with a host. The cryptographic iButton is one of the least counterfeitable devices. In response to tampering, the cryptographic iButton would rather erase the key than reveal its secrets [61]. Dallas provides some software tools and hardware accessories to develop iButton applications and software. Authorized software developer (ASD) and original equipment manufacturers (OEM) need to register at Dallas Semiconductors and can be reached through Dallas Semiconductors on-line catalog, iButton Connections [62]. Applications
There are currently more than 27 million iButtons in use around the world [58], and more than half of those are being worn by people. The reasons for wearing a chip every day include opening a locked door, logging onto a computer, using a coin purse, carrying medical information or citizen credentials (drivers license, passport), or conducting Internet transactions. Digital jewelry is the term Dallas Semiconductors uses for iButton accessories that are to be worn every day as a carefully guarded accessory [59]. They range from a ring (also known as the JavaRing), to key chains, wallets, metal cards, watchesbasically objects that people are practiced how not to lose. Of all the forms available, the JavaRing is the one most notable one: The Java-powered ring consists of the Java-powered iButton mounted on a jewelry-grade, stainless steel (or solid gold) ring. The memory iButton is also available in ring form as the digital decoder ring. The iButton store [59] presents more details. The buttons unique form factor and features address widespread cultural and economic needs to identify and authenticate, time- and date-stamp events, guard property, and track inventory. Some of the larger installations of memory iButtons include the U.S. Postal Service, which has iButtons affixed to blue corner mailboxes nationwide so they can do the tracking needed to ensure on-time delivery of the mail. Ryder has its entire truck fleet fitted with iButtons that track vehicle maintenance. Citizens of Istanbul, Turkey, store digital cash in the iButton, using the device as a small change purse on their mass transit system. The cryptographic iButton is currently undergoing beta tests with the U.S. Postal Service as a security device to download postage off the Internet, which users can then print from their own desktop printers.
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Other iButton applications include the following: • Asset management; • E-commerce (i.e., cashless transactions for transit systems, vending
• • • • • • • • • • •
machines, parking meters, gas stations, on-line-certification, and secure automatic communication with digital signatures); Facilities management (tour watch, equipment maintenance, access control, security); Security; Lead collection systems; Time and attendance; Manufacturing process control; Software authorization; Transportation; Health care (patient records, emergency medical, and equipment calibration); Chemical procedures (store parameters); Maintenance (of vehicles, equipment, and facilities); Fleet refueling.
Additional details of iButton applications can be found at iButton Applications on the Web [60]. 3.3.3
Tag Technologies
The object of any identification system is to carry data in suitable units or devices, known as tags, and to retrieve data, by machine-readable means, at a suitable time and place to satisfy particular application needs. Data within a tag may provide identification for an item in manufacture, goods in transit, a location, or the identity of a vehicle, an animal, or individual. Including additional data would support applications through item-specific information or instructions immediately available on reading the tagfor example, the color of paint for a car body entering a paint spray area on the production line, the setup instructions for a flexible manufacturing cell, or the manifest to accompany a shipment of goods. New feature and developments bring new benefits and create new automatic identification and data capture (AIDC) applications.
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3.3.3.1 Bar-Code Technology
Using a bar code is the simplest way to tag items. Bar codes are machinereadable code symbologies printed directly on an item or on a sticker attached to the item. They basically act as license plates for a database. There are many different bar-code symbologies, or languages. Each symbology has its own rules for character (e.g., letter, number, punctuation) encoding, printing and decoding requirements, error checking, and other features. The various bar-code symbologies differ both in the way they represent data and in the type of data they can encode. Some only encode numbers; others encode numbers, letters, and a few punctuation characters; still others offer encoding of the 128-character, and even 256-character, ASCII sets. The newest symbologies include options to encode multiple languages within the same symbol, allow user-defined encoding of special or additional data, and even allow (through deliberate redundancies) reconstruction of data if the symbol is damaged. In 2000 there were about 225 known barcode symbologies, but only a handful of these are in current use and fewer still are widely used [61]. There are three basic types of bar codes: linear, 2D, and composite. Linear bar-code symbols are easily identified by their tall printed bars of varying widths. Two-dimensional bar-code symbols are broken into two major groups called matrix symbologies and multirow bar codes. Matrix symbologies look like a matrix of printed dots, and multirow bar codes look like linear bar codes with very short bars stacked on top of each other. Composite symbols are a category of bar codes that combine interdependent linear and 2D symbols. Bar-Code Common Applications
Widespread use of bar-code technology began 20 years ago in the supermarket industry and achieved great success: virtually every grocery supplier now uses the universal product code (UPC) [62] symbol on product packaging to enable point-of-sale (PoS) scanning. Mass merchandisers as well as a wide range of nongrocery retailers have followed grocers leads so that PoS scanning is now a common fact of retail life. In an effort to decrease costs and improve productivity, bar-code technology became a priority for nearly every industryfrom utilities to health careespecially in materials management (a.k.a. logistics) applications. Retail businesses that previously used bar codes only at PoS followed Wal-Marts lead to automate their warehousing and transportation functions and reaped tremendous cost benefits.
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Bar-code technology is also used extensively for such applications as access control, asset tracking, cataloging of books and files by libraries and archives, document management, hazardous waste tracking, package tracking and delivery, and vehicle control and identification. Bar-Code Disadvantages
While the bar code has enabled mechanized data capture, it has not realized the dream of automated data capture. Customers who have adopted bar-code systems still face the following limitations: • The ability to read only one bar code at a time; • The necessity for the bar code to be totally exposed in direct line of
sight at a specific angle or range of angles;
• The fact that bar-coded tags cannot be covered with dirt, moisture,
dust, or other substances, and, despite improvements, are still prone to ink bleeding, stray marks, dropouts, label warping, and label tearing.
• Requirements for human labor to either face the asset appropriately
for scanning or to perform the actual scanningthis is costly and introduces a chance of error;
• The fact that bar-coded information cannot be erased, rewritten, or
appended;
• The fact that bar codes can easily be copied, allowing counterfeit use
and compromise;
• The inability of bar coding to provide local information, in contrast
to other tagging (radio frequency) technologies.
3.3.3.2 Radio Frequency Identification
Radio frequency identification (RFID) is a relatively new AIDC technology that first appeared in tracking and access applications during the 1980s. These wireless AIDC systems allow noncontact reading and consequently are effective in manufacturing and other hostile environments where bar-code labels could not survive. RFID has established itself in a wide range of markets, including livestock identification and automated vehicle identification (AVI) systems, because of its ability to track moving objects. The technology has become a primary player in automated data collection, identification, and analysis systems worldwide. In contrast to bar code, RFID systems
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provide both identification of items and also local memory for data collection purposes. This section first presents technical details of RFID systems (basic RFID system, RFID tags, frequencies, data transfer rate and bandwidth, data carrying options, costs, and reader or interrogator) and then of RFID characteristics (advantages, developments, standardization, system categories) and applications. Basic RFID System
A basic RFID system consist of three components: 1. A transponder (commonly called a RF tag) that is electronically programmed with unique information; 2. A transceiver with decoder (can also be mobiletethered, handheld, or wireless); 3. An antenna or coil. Figure 3.36 shows the RFID system components, described as follows: • The host has access to a software database. • The reader interprets radio frequency into digital information. • The RF module receives and transmits radio frequency signals
through the antenna. • The tag (transponder) is interrogated by the antenna. The antenna captures the tag ID number and other data (to which it is granted access) first as analog RF waves, then it is converted to digital information. Application software
Antenna
4
RFModule module RF
1
3
HOST HOST
Reader Reader 2
Figure 3.36 Basic RFID system.
RF tag
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The antenna emits radio signals to activate the tag and read and write data to it. Antennas are the conduits between the tag and the transceiver, which controls the systems data acquisition and communication. Antennas are available in a variety of shapes and sizes; they can be built into a door frame to receive tag data from persons or things passing through the door, or mounted on an interstate toll booth to monitor traffic passing by on a freeway. The electromagnetic field produced by an antenna can be constantly present when multiple tags are expected continually. If constant interrogation is not required, the field can be activated by a sensor device. Often the antenna is packaged with the transceiver and decoder in order to serve as a reader (a.k.a. interrogator), which can be configured either as a handheld or a fixed-mount device. The reader emits radio waves in ranges of anywhere from 1 in to 100 ft or more, depending upon its power output and the radio frequency used. When an RFID tag passes through the electromagnetic zone, it detects the readers activation signal. The reader decodes the data encoded in the tags integrated circuit and the data is passed to the host computer for processing. A very detailed description of RFID technology is Radio Frequency IdentificationA Basic Primer [63]. RFID Tags
RFID tags come in a wide variety of shapes and sizes. Animal tracking tags, inserted beneath the skin, can be as small as a pencil lead in diameter and 0.5 inch in length. Tags can be screw-shaped to identify trees or wooden items, or credit-card shaped for use in access applications. The antitheft hard plastic tags attached to merchandise in stores are RFID tags [64]. In addition, heavy-duty 5 × 4 × 2in rectangular transponders used to track intermodal containers or heavy machinery, trucks, and railroad cars for maintenance and tracking applications are RFID tags as well. Physical dimensions are not the only distinctions of tags: They also differ in memory size (25 bits to 512 KB and more [65]), memory kind (readonly, read-write, write-once-read-many), memory type [EEProm, Antifuse, ferroelectric RAM (FRAM)] [66], arbitration (anticollision: read-write one or many tags at a time), and price. RFID tags can be categorized as either active or active/passive backscatter. Active RFID Tags
Active RFID tags are powered by an internal battery and are typically readwrite (i.e., tag data can be rewritten or modified). An active tags memory
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size varies according to application requirements (some systems operate with up to 1 MB of memory). In a typical read-write RFID work-in-process system, a tag might give a machine a set of instructions, and the machine would then report its performance to the tag. This encoded data would then become part of the tagged parts history. The battery-supplied power of an active tag generally gives it a longer read range (Intermec: 300 ft [66]). The trade-off is greater size, greater cost, and a limited operational life (which may yield a maximum of 10 years, depending upon operating temperatures and battery type). The battery in this kind of tag serves memory, radio, and circuitry. Backscatter RFID Tags
Backscatter technology is a RF technology that passes power through electromagnetic signals. It requires close proximity of the participating devices, but no physical contacts. There are two basic kinds of backscatter RFID tags that obtain power generated from the reader: active and passive backscatter RFID tags. Both are consequently much lighter than active tags, less expensive, and offer a very long operational lifetime. The trade-off is that they have shorter read ranges than active tags and require a higher-powered reader. Active Backscatter RFID Tags
Active backscatter RFID tags have a small battery of their own that only powers memory and circuitry. Backscatter technology is used to activate the tag and the transmission. This architecture allows the tags to keep and compute data without being dependent on the readers power source and without having to carry around a heavy and, compared to the tag, big battery. Compared to active tags, active backscatter tags provide a much greater lifetime, but also a shorter, medium read range (Intermec: 1050 ft [66]). Passive Backscatter RFID Tags
Passive backscatter RFID tags have no battery of their own and are 100% reader powered. They offer the shortest read range (Intermec: 4 in15 ft [66]), but have a virtually unlimited operational lifetime. Read-only tags are typically passive backscatter and are programmed with a unique set of data (usually 32128 bits) that cannot be modified. Read-only tags most often operate as a license plate into a database, in the same way as linear bar codes reference a database containing modifiable product-specific information. One passive backscatter RFID system application is for electronic article surveillance (EAS) in merchandise stores [64].
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Frequencies
Radio frequency communication channels are separated on the basis of frequency allocation. This is generally covered by government legislation, with different parts of the electromagnetic spectrum being assigned for different purposes. Allocations may differ depending on the governments concerned, which requires care in considering RFID applications in different countries. Standardization efforts are seeking to obviate problems in this respect. Three frequency ranges are generally distinguished for RFID systems: low, medium, and high. Table 3.15 summarizes these three frequency ranges, along with the typical system characteristics and examples of major areas of application. Figure 3.37 shows the RFID frequency allocation in comparison to other systems. Choice of field or carrier wave frequency is of primary importance in determining data transfer rates. In practical terms the rate of data transfer is influenced primarily by the frequency of the carrier wave or varying field used to carry the data between the tag and its reader. Generally speaking the higher the frequency the higher the data transfer or throughput rates that can be achieved. This is intimately linked to bandwidth or range available within the frequency spectrum for the communication process. The channel bandwidth needs to be at least twice the bit rate required for the application in mind. Where narrow band allocations are involved the limitation on data rate can be an important Table 3.15 Frequency Bands for RFID and Applications Frequency Band
Characteristics
Typical Applications
Low 100500 kHz
Short to medium read range Inexpensive Low reading speed
Access control Animal identification Inventory control Car immobilizer
Intermediate 1015 MHz
Short to medium read range Potentially inexpensive Medium reading speed
Access control Smart cards
High 850950 MHz 2.45.8 GHz
Long read range High reading speed Line of sight required Expensive
Railroad car monitoring Automated toll collection systems
Source: [63].
Technologies RFID: access control animal ID Low Freq. EAS
RFID: smart cards Mid Freq. EAS
Radio toys AM
Data modem
10 kHz
100 kHz
1 MHz
CB
10 MHz
175 RFID: toll roads and item management
Data terminal
TV Garage FM door
100 MHz
RFID: item management Microwave EAS
Cell phone
1000 MHz
2.45 GHz
3.0 GHz
Figure 3.37 RFID frequency allocation. (Source: [66].)
consideration. It is clearly less of an issue where wide bandwidths are involved. Using the 2.42.5 GHz spectrum, for example, 2 megabits per second data rates may be achieved, with added noise immunity provided by the spread spectrum modulation approach. [63] Data Carrying Options
Data stored in data carriers invariably requires some organization and additions (such as data identifiers and error detection bits) to satisfy recovery needs. This process is often referred to as source encoding. Standard numbering systems and associated data defining elements may also be applied to data stored in tags. The amount of data will, of course, depend on application and require an appropriate tag to meet the need. Basically, tags may be used to carry the following: • Identifiers, in which a numeric or alphanumeric string is stored for
identification purposes or as an access key to data stored elsewhere in a computer or information management system;
• Portable data files, in which information can be organized for com-
munication or as a means of initiating actions without recourse to, or in combination with, data stored elsewhere.
In terms of data capacity, tags can be obtained that satisfy needs from single bit to kilobits. The single-bit devices are essentially for surveillance purposes. Retail EAS is the typical application for such devices, being used to activate an alarm when detected in the interrogating field. They may also be used in counting applications.
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Devices with data storage capacities up to 128 bits can hold a serial or identification number together, possibly, with parity check bits. Such devices may be manufacturer or user programmable. Tags with data storage capacities up to 512 bits are invariably user programmable and suitable for accommodating identification and other specific data, such as serial numbers, package content, key process instructions, or possibly results of earlier interrogation-response transactions. Tags characterized by data storage capacities of around 64 Kb may be regarded as carriers for portable data files. Increased capacity can provide for the organizing of data into fields or pages that may be selectively interrogated during the reading process. Costs
The cost of tags obviously depends upon the type and quantities that are purchased. For large quantities (tens of thousands) the price can range from less than a few tens of cents for extremely simple tags to tens of dollars for the larger and more sophisticated devices. Increasing complexity of circuit function, construction, and memory capacity will influence cost of both transponders and reader/programmers. Reader/Interrogator The reader/interrogators can differ quite considerably in complexity, depending upon the type of tags being supported and the functions to be fulfilled. However, the overall function is to provide the means of communicating with the tags and facilitating data transfer. Functions performed by the reader may include quite sophisticated signal conditioning, parity error checking and correction. Once the signal from a transponder has been correctly received and decoded, algorithms may be applied to decide whether the signal is a repeat transmission, and may then instruct the transponder to cease transmitting. This is known as the command response protocol and is used to circumvent the problem of reading multiple tags in a short space of time. Using interrogators in this way is sometimes referred to as hands down polling. An alternative, more secure, but slower tag polling technique is called hands up polling, which involves the interrogator looking for tags with specific identities, and interrogating them in turn. This is contention management, and a variety of techniques have been developed to improve the process of batch reading. A further approach may use multiple readers, multiplexed into one interrogator, but with attendant increases in costs. [63]
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RFID Advantages
The significant advantage of all types of RFID systems is the noncontact, non-line-of-sight nature of the technology. Tags can be read through a variety of substances (snow, fog, ice, paint, crusted grime, and other visually and environmentally challenging conditions), where bar codes or other optically read technologies would be useless. RFID tags can also be read in challenging circumstances at remarkable speeds, in most cases responding in less than 100 ms. Multiple tags can be read simultaneously, too. The read-writeappend capability of an active RFID system is also a significant advantage in interactive applications, such as work-in-process or maintenance tracking. Also, compared to bar codes, they have a longer life. Since they can be encapsulated, they can be used to autolocate tagged objects, and one does not have to physically see the tags to read them. Though it is a costlier technology (compared with bar code), RFID has become indispensable for a wide range of automated data collection and identification applications that would not be possible otherwise. RFID Developments
Developments in RFID technology continue to yield larger memory capacities, wider reading ranges, and faster processing. It is highly unlikely that the technology will ultimately replace bar codeeven with the inevitable reduction in raw materials coupled with economies of scale, the integrated circuit in an RF tag will never be as cost-effective as a bar-code label. However, RFID will continue to grow in its established niches where bar code or other optical technologies are not effective. If some standards commonality is achievedwhereby RFID equipment from different manufacturers can be used interchangeablythe market is likely to grow exponentially. New features will bring new benefits and create new applications. If the unique advantages and flexibility of RFID is the good news, then the proliferation of incompatible RFID standards is the corresponding bad news. All major RFID vendors offer proprietary systems, with the result that various applications and industries have standardized on different vendors competing frequencies and protocols. The current state of RFID standards is one of severe disarraystandards based on incompatible RFID systems exist for rail, truck, air traffic control, and tolling authority usage. The U.S. Intelligent Transportation System and the U.S. Department of Defense (DOD) Total Asset Visibility system are among other special-interest applications. Also, ANSIs X3T6 group, comprising major RFID manufacturers and users, is currently developing a draft document-based systems operation at a
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carrier frequency of 2.45 GHz, which it is seeking to have adopted by ISO. ISO has already adopted international RFID standards for animal tracking, ISO 11784 and 11785 [63]. RFID System Categories
RFID systems may be roughly grouped into four categories: 1. 2. 3. 4.
EAS systems; Portable data capture systems; Networked systems; Positioning systems.
EAS systems are typically a 1-bit system used to sense the presence or absence of an item. The largest use for this technology is in retail stores where each item is tagged and large antenna readers are placed at each exit of the store to detect unauthorized removal of the item (theft). Portable data capture systems are characterized by the use of portable data terminals with integral RFID readers and are used in applications where a high degree of variability in sourcing required data from tagged items may be exhibited. The handheld readers, or portable data terminals, capture data, which is then either transmitted directly to a host information management system via a radio frequency data communication link or held for delivery by line-linkage to the host on a batch processing basis. Networked systems applications can generally be characterized by fixedposition readers deployed within a given site and connected directly to a networked information management system. The transponders are positioned on moving or moveable items, or people, depending upon the application. Positioning systems use transponders to facilitate automated location and navigation support for guided vehicles. Readers are positioned on the vehicles and linked to an onboard computer and a link to the host information management system. The transponders are embedded in the floor of the operating environment and programmed with appropriate identification and location data. The reader antenna is usually located beneath the vehicle to allow closer proximity to the embedded transponders. RFID Applications
RFID systems serve a broad range of applications, from transportation and distribution, industrial applications, to security, access control, and identification.
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For example, RFID systems are suited for use in the rigorous rail environment. Field programmable tags permit the full industry standard 12character identification of each car by type, ownership and serial number. Tags are attached to the vehicle undercarriage; antennas are installed between or adjacent to the tracks, and readers or display devices are typically located within 40 to 100 feet in a wayside hut along with other control and communications equipment. A primary objective in rail applications is the improved fleet utilization that permits reductions in fleet size and/or deferral of investment in new equipment [66]. In the plant environment, RF systems are ideally suited for the identification of high-unit-value products moving through a tough assembly process (e.g., automobile or agricultural equipment production where the product is cleaned, bathed, painted and baked). RF systems also offer the durability essential for permanent identification of captive product carriers, such as the following: • Containers, barrels, tubs, and pallets; • Tool carriers, monorail and power, and free conveyor trolleys; • Lift trucks, towline carts, and automatic guided vehicles.
Primary applications fall into two basic categories: 1. Direct product identification wherein the tag specifically identifies the item to which it is attached (e.g., by part or serial number or, in the case of read-write systems, assembly or process instructions for the item). 2. Carrier identification where content is identified manually (or with a bar code reader) and fed to the control system along with the carriers machine-readable RF license plate number. Strategically deployed RF readers accomplish subsequent load tracking. 3. The automotive industry uses RFID systems to track vehicles through assembly, where tags must perform even after repeated subjection to temperatures of 150°C to 200°C, painting, and the like. A primary objective for use of the technology in this environment is verification of vehicle identity prior to execution of given assembly tasks. Although manufacturers sequentially track vehicles through assembly, undetected removal of a single vehicle from the line could be costly.
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4. Because RFID tags need not be seen to be read, they can be buried within pallets, tote boxes, and other containers and provide solid performance for the life of the carrier. As an example, in a casting operation RF tags are attached to wire baskets which travel through a variety of degreasing, etching and cleaning tanks by means of an overhead power and free conveyornot a job for optical or magnetic identification media. 5. In a manner similar to carrier identification, RF tags can be used for tool management. Miniature tags can be placed within tool heads of various types, such as block or Cat V-flange, or even within such items as drill bits where individual bits can be read and selected by reader guided robot arms. 6. RFID systems are used for lift truck and guided vehicle identification in a number of installations. One approach buries tags at strategic locations throughout the facility and verifies vehicle location via onboard battery-powered readers. Other users station readers at the ends of warehouse aisles to monitor lift truck activity. Here, throughput rates permit multiplexing multiple antennae per reader. [66] Animal Identification Valuable breeding stock, laboratory animals involved in lengthy and expensive research projects, meat and dairy animals, wildlife, and even prized companion animals all present unique identification problems that can be solved by innovative applications of RFID technology. [66] Future RFID Applications
New and future RFID applications include the following: • Vehicle gas (petroleum) dispensing; • Automatic toll systems; • Vehicle immobilization; • Laundry automation; • Gaming; • Ski lifts; • Sports timing.
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There are, however, certain barriers to those new applications, such as the following: • High tag price (mostly application-specific custom-designed tags) • Competition from existing and established technologies; • End-user education; • Lack of standards.
The need for standards and education is emerging for the following reasons: • RFID is a relatively new technology comprised of many varia-
tionsthere is need to educate users and suppliers.
• RFID has a proprietary historythere is the need for compatibility
and for multiple sources.
3.3.3.3 Smart Tags
Smart tags are based on the idea that all objects are equipped with some kind of smart RFID tag. They will serve a huge range of applications and will vary in features and physics according to the type of application. A future standardization process will ensure technical compatibility between RFID systems. There are different kinds of smart tags. Physical forms depend on the type of application: printable (with conductive ink), disposable, environmentally friendly RFID labels (with IC chip, also called smart labels), rugged tags, indestructible tags, with and without battery, embedded tags, waterand chemical-proof tags, encapsulated tags, and many more. Their features include lifetime, reusability, read-write or modifiable, read-range, level of smartness, and context-awareness. Attaching smart tags to objects basically enables automatic wireless object identification and object location tracking. The following list presents possible uses of smart tags: • Automatic identification of items in stores for automatic inventory,
automatic reading of goods at the cash desk, and replacement and improvement of EAS systems (These would not involve line-of-site or human labor requirements. Smart tags are a single technology encompassing both security and operational improvements);
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• Simple, automatic book checkout and return in libraries; automati• • •
• • • • • •
cally generated circulation data; All applications where bar code resides and beyond; Instructions for handling, cleaning, and washing laundry; Automatic identification and location of inventory in warehouses and storerooms, precious objects in museums and at home, or equipment in hospitals (Every item or object can tell its current location and usage. Nothing will magically disappear, and users will have constant information and will quickly find lost objects); Identification of precious pets; Automatic object processing at customs offices or the department of commerce and in military, police, and related scenarios; Automatic gas (petroleum) dispensing and toll systems; Automatic immobilization; Gaming, ski lifts; Sports timing (the tag identifies the athlete).
Building upon these general features, the following application scenarios are possible: • Multifunctional smart tag in cars. Automatic toll collection; auto-
matic payment in car parks; safety data (dangerous bends, slippery conditions, bridge clearanceradar tag with appropriate warning stations [67]); traffic warnings (distance to other carsradar tag [67]); status and movement monitoring, as well as location tracking while user is absent (against burglary, theft, collisions); automatic vehicle localization with users handheld device (location of the car in multistory car parks); access the car through the handheld device to make it honk, to read information about it (self-describing car for car dealers and sales, on the assembly line). • Smart tags to identify pets. Tags can be implanted or attached to the animals collar. When pets run away, or are lost or stolen, smart tags can locate them. Some pets could even be educated to follow orders when the tag gives signals (e.g., to make it come home). One simple RFID system for pets, called electric fence, is already on the marketan electric tag gives electroshocks to the pet when it leaves the predefined areas electromagnetic field.
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• Smart tags to improve security. Smart tags (small, rugged, indestructi-
ble tags) identify valuable objects in museums, warehouses, stores, and at home, and prevent theft by periodically sending out status reports. Unusual movements can be detected, too (in case of burglary, additional equipment is necessary). Affixed to a valuable object, the tag receives a remotely generated request for status information and, responsive to the request, transmits its data to a remote device. The radio tag or label is affixed to the object in a manner so that it is rendered inoperative if the object is tampered with. By remotely monitoring the status information on a periodic basis, the security of the object can thus be determined.
• Smart tags in consumer package delivery. Smart tags allow automatic
localization of packages inside a delivery van. The drivers handheld or the van itself tells the position of the packages destined for this address. The driver can pick up the right packages without a long search. Sometimes the driver has to unload several other packages to get to the right one. Afterwards, the van or the handheld device tells the driver how best to put the packages back, so that the driver can unload them quickly at the next destination. The van or handheld could also check whether all packages are reloaded, double-checking cargo to prevent false deliveries.
• Smart tags for consolidating cargo transportation companies. This
would enable automatic and full cargo tracking and enhance automation and logistics. Only a few cargo transportation companiesthe major ones like UPS and Federal Expresshave complete cargo tracking networks, and a complete end-to-end packet transportation system based on their extensive infrastructure of local offices and distribution centers worldwide, including a huge fleet of aircraft, ships, and vehicles. High-level cargo tracking is a business advantage in comparison to consolidating package distribution companies, which cover only specific parts of the cargos trip. Those companies do not have a complete transportation fleet of their own and need to consolidate. As many of them use different systems, they cannot provide full tractability. Also, the heterogeneity of their software and delivery systems results in lower reliability and higher management complexity. To make their track- and transportsystems compatible would require an immense effort. However, using smart tags for communication on independent cargo containers can overcome the disadvantages. The cargo containers would
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communicate independently with a service station, which then knows both the containers location, and the ongoing transportation process across all carriers. Cargo is then traceable at all times. This application requires a smart tag that extends the features of todays fleet tracking devices with a GPS receiver and cellular communication like that used in automatic vehicle tracking (AVT). • Smart tags in production. The tag identifies the item, explains pro-
duction instructions, and keeps an unalterable log of each step in the handling of the controlled item. This applies to hardware on conveyor belts (like cars and clothes) and any other produced hardware. The unalterable log applies specifically to mission-critical items to check its production and its handling.
• Smart tags in clothing to enable automatic laundry. A smart laundry
system includes a tag-communicating device for reading laundering instructions contained in the tag attached to a material item while the material item is within the laundry machine. The system controls the laundry machine in accordance with the laundering instructions. The electronic tag maintains a count of the number of launderings of the material item. An automatic folding and sorting machine folds and sorts the material item based upon folding and sorting instructions stored on the tag. Soft fabric stretch sensor tags knitted into the clothing can be used for this. A tag-programming device is used to identify, locate, query, and program the tag.
• Smart tags on articles in shops and stores. Automatic inventory systems
scan all aisles regularly. At the point of sale, customers do not have to put their articles on the conveyor belt, but articles just stay in the cart and a detector scans the cart automatically and calculates the price instantly. To prevent theft, detectors at exits or checkout aisles create a surveillance zone to control proper shopping (it annoys users when staff controls their shopping bags after payment). The smart fridge (with an RF detector and embedded computer) at home and in the supermarket knows its content and the expiration dates of perishable food. It keeps track of food supplies and sends messages to users about the state of the food and of the fridge. An Internet-connected smart fridge can automatically order on-line on behalf of its user.
• Smart-tagged articles in libraries. Tagging books, videotapes, and
any other kind of media would enable an automatic inventory control system. An inventory database tracks all tagged articles and
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maintains their circulation status information. Articles are checked out of the library by a self-checkout system. Return of articles to the library is done by depositing them into an exterior smart drop box that reads the RFID tag and automatically checks the article back in. Article data from the exterior smart drop box is used to generate reports for efficiently reshelving the articles. Articles that are used in the library, but not checked out, are returned to interior smart drop boxes within the library for reshelving. The interior smart drop boxes capture data regarding in-house use of articles. The data is used to generate historical usage reports. The uncirculated articles are stored on shelves of the library. The shelves are periodically scanned with RFID scanners for updating inventory status. • Smart tags in medicine. Tags on medicine or drug boxes, in combi-
nation with smart medicine cabinets, allow monitoring and control of drug consumption in hospitals and retirement homes. Smart medicine cabinets identify tagged drugs and measure their consumption. By identifying users, it can track the use of medicine relative to users and patients.
3.3.3.4 Smart Tag Examples
In general, smart refers to the ability of humans to think quickly or cleverly in difficult situations. Applied to objects like tags, it means that they are able to react to special circumstances in a clever way. Some of the currently developed so-called smart tags do have this feature, like the Digital Angel or the BadgePAD, but most of them are simply RFID tags with special or advanced features. As such, a smart tag would then basically consist of an active RFID tag with rewritable memory and an IC silicon chip to execute some predefined or programmable operations, as well as some sensors to enable some form of context or location-awareness. With their basic RF com- munication ability, they can respond to queries or initiate their own communication. Such tags are used in special applications. So far, no broad applications (and no standards) exist that would ask for such devices. However, on customer demand, RFID manufacturers are willing to integrate IC silicon chips into their RFID tags and equip them with sensors of any type (e.g., Savi Technology [68] and IDMicro [69] are keen on placing IC chips into tags). Smart tag implants can be used for the identification of pets. The chip, a powerless device the size of a grain of rice, is injected under the animals skin with a special syringe. Each chip is programmed with a distinctive ID
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number that can be read using a scanner. The number is linked to a database containing information about each animal. Such systems have already been in use for a couple of years (e.g., to track endangered species in the wilderness), but new developments make this technology affordable to private customers and pet owners. One such new development is the Digital Angel of Applied Digital Solutions. While a number of tracking and monitoring technologies have been patented and marketed in the past, they are all unsuitable for the widespread tracking, recovery and identification of people due to a variety of limitations, including unwieldy size, maintenance requirements, insufficient or inconvenient power-supply and activation difficulties. Now, for the first time in the history of location and monitoring technology, Digital Angel of Applied Digital Solutions Inc. should overcome these limitations [70]. This implantable device is inserted in humans just underneath the skin and has a maintenance-free regenerating power supply. It is a miniature digital transceiver that can be used for a variety of purposes, such as providing a tamperproof means of identification for enhanced e-business security, locating lost or missing individuals, tracking the location of valuable property, and monitoring the medical conditions of at-risk patients (it can monitor certain biological functions, such as heart rate). This device can thus spawn applications in e-business, business security, health care (such as emergency location and medical monitoring), and criminal justice. The implantable transceiver sends and receives data and can be continuously tracked. When implanted within a body, the device is powered electromechanically through the movement of muscles, and it can be activated either by the wearer or by the monitoring facility. Another feature will even allow the wearer to control the device to some degree. The smart device is also small enough to be hidden inconspicuously on or within valuable personal belongings and priceless works of art. Smart Tag also refers to a smart travel service in the commonwealth of Virginia [71]. Its product, Smart Tag, is an electronic toll collection system for prepaying road and highway tolls. A Smart Tag transponder, placed on the inside of the cars windshield, communicates through a RF link with a computer in the lane at the toll plaza. The amount of the toll is then subtracted from the prepaid Smart Tag account. This tag is a RFID tag with its own power supply, but no memory and no IC. Transintel [67] has a 77-GHz Radar Smart Tag that passes critical safety data like bridge clearance, piers, other fixed objects, as well as guide signs, speed limits, and hazard warnings to vehicles. The system is intended as a radar smart tag infrastructure that helps adaptive cruise control and collision warning.
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One context-aware device in the works at Hewlett Packard Labs [72] is BadgePAD, a smart badge that might be used in a work setting. In a hospital, for instance, doctors could pick up a BadgePAD when they arrive at work. The badge would know what is going on around the physician because Web servers would be embedded throughout the facility. Everyone elsenurses, orderlies, technicians, administrators, and even patientswould also wear the badges. In that setting, the hospital records system would recognize a doctor when he or she entered the patients room and relevant charts would automatically pop up on the computer screen. If someone approached the screen who was not authorized to see the patient information, it would go blank. The BadgePAD would know when the doctor put it down, and if someone else picked it up, it would have a whole different set of e-services personalized for that person. This project belongs to HP Labs Cooltown project [73]. Another interesting new development is BiStatix from Indala Corporation, a subsidiary of Motorola. BiStatix is a smart label technology that allows the creation of cost-effective smart labels: RFID antennas can be printed on materials (including paper) with conductive nonmetallic silicon ink. This process is environmentally friendly, disposable, cheap, and uses adhesive to be attached to items. These smart labels contain information that can be both read and modified through a wireless interface, enabling tracking and efficient routing of objects, including airline baggage, packages, and parcels. The BiStatix technology, based on a capacitively coupled design, creates an advanced, cost-effective RFID solution with advanced antenna technology. Because it uses only silicon and printed ink, it delivers a significant enhancement to earlier generations of RFID technology, which required the incorporation of a costly metal coil and resonant capacitor into a card or tag. [74] 3.3.3.5 Smart Keys
A smart key is a personal computing device that identifies and authenticates a user, and stores private user data and user preferences. It acts as a key, as an electronic purse, as a user smart card, and can run multiple applications and access services. In that functionality, the smart key is also a means for tangible capabilities. Tangible capabilities refer to a subset of tangible bits (defined in [75]) that allow a user to electronically grab or buy electronic items and products with a smart key and to use the items later at another place. The user thus bought the capability to access and use the item in an electronic
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form. To the user, it looks as if he really bought the item and put it into his smart key. Examples include buying movies or music files, and watching or listening to them later. From the technological point of view, a smart key has the following characteristics: • It is a portable or wearable, physically safe, hardware unit (like the
iButton) that can also be integrated into watches, jewelry, and the like.
• It consists of a multiapplication smart-card chip with memory. • It has some form of wireless communication (RF) or quick-touch
communication (i.e., skin conductance, or touching an object quickly with the fingertips, transmits the data via a PAN).
• It has an intelligent network infrastructure that only knows as much
as necessary.
Such a smart key would finally make the dream of the universal device come true. It could combine the functionality of all small user devices that are currently in place: credit cards, debit cards, money cards, health insurance smart cards, smart cards for user identification for vehicles, mass transit cards, iButton, telephone cards, membership cards, identification and access cards, bonus programs, and many more. The idea of such a smart key is not new, and although all required technologies exist today, no one has developed such a device. One of the reasons is there is no platform upon which to give this device a quick start and large installed base. Meanwhile, mobile phones with WAP-based Internet access are used (BMW, Volkswagen, DaimlerChrysler). The personal smart key is also the perfect means to store a users e-dentity [76], or electronic identity (e.g., digital certificates). The smart key can be designed to be the next-generation ID card that holds the electronic credentials of the user and serves as the users proof of identity. The currently developed public key infrastructure X.509 standard by the IETF could be used for this. 3.3.3.6 Smart Interconnected Home Appliances
Smart interconnected appliances are smart household and entertainment appliances that are interconnected by a home network infrastructure like HAVi, Universal Plug and Play (UPnP), open services gateway initiative (OSGI), or consumer electronics business (CEBus). This home network also
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establishes a connection to the Internet and allows appliances to represent themselves by Web pages or as Jini objects. This setup enables cooperation among appliances at home, and users can control and operate them through other appliances or through the Web, either by a PC, a Web access device, or a WAP-enabled mobile handset or phone. Users have both total control of appliances at home and are able to check their status while away from home. Smart appliances include stoves, microwaves, refrigerators, washers and dryers, HVACs, light systems, window blinds, VCRs, hi-fi audio equipment, tuners, amplifiers, clocks, AV disc players, digital music players, displays (monitors and TVs), digital cameras, modems, set-top boxes, Web proxy and converters, smart cabinets, smart furniture, smart walls, and many, many others. The following scenarios are possible: • Home agent or assistant: This intelligent software agent running
on the home application server controls all devices at home and provides the command and control interface to the user. It also connects to the users car and to the users smart phone (or PDA or handheld) to remind the user of important events and calls (it can also reroute important calls). It runs a synchronized calendar, maintains a shopping list, and delivers memos that are then accessible from any place (the mobile phone, PDA, a smart wall at home, a smart desk).
• HVAC and lights: When nobody is at home, the home network (i.e.,
the home agent) can turn the HVAC and light system on and off. When people are at home, only occupied rooms may be operated. This scenario requires sensors that tell the home network where users are.
• Window blinds: These can be opened and closed according to time
of day (sunrise or sunset) and special user-defined conditions. Users can also operate them from any device.
• Smart fridge: This device knows its content and tells the home assis-
tant, and thus the user, that perishable food should be used up, what items needs to be bought, and so forth. The home agent can either put this on the users shopping list, or order it automatically from a shop. The latter way allows integration into the supply chain that extends from the grocer to the home in order to relieve the consumer of tedious shopping chores. The smart fridge can also allow consumers to scan a frozen dinner, and then tell the stove the right
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•
•
•
•
•
temperature to cook the meal and also order another dinner from the local grocery store. Smart medicine cabinet: This device knows its contents on drugs (that is, knows the kind of drug and the amount) and the authorized users. It can thus control user access to drugs and monitor user-dependent drug consumption. It forwards this information to the home agent, which in turn informs doctors and rescue, if necessary. Multiple access points to information by interconnected appliances: The stove, the microwave, the fridge, the TV, or any other appliance can provide access to the home network and forward information to the right applications (e.g., a detachable tablet-shaped computer in the door of the fridge, integrated into the microwave or the stoves door). They also can keep grocery lists (and automatically purchase them via the Net), access phone numbers, schedules, recipes, and check on laundry. Interoperable home appliances: Wherever the user stays in the building, calls are forwarded to him, or the nearest phone; videotelephony is forwarded to the nearest TV or monitor. Entertainment devices like the game console already use the TV screen, and in the future might use the PCs modem to interconnect players. A digital camera could automatically use the hard disc of the PC and the TV screen as output. Home appliances can also access remote digital network services, such as a storage service for large video filesa media service could provide newspaper printing services directly to a customers home printer. Remote control: Users can operate digital electronics products in their homes (like digital AV appliances and home entertainment systems and PCs) from remote or mobile locations, through the mobile phone, the PDA, or a computer connected to the Internet. Virtual teams: An interactive information and cooperation network can establish a work environment for creativity teams. Such an environment might include interactive connected electronic walls [77], interactive tables [77], or computer-augmented chairs [77]. It would be a flexible and dynamic environment with cooperative workspaces to support and augment human communication and collaboration and provide context-sensitive information according to knowledge about past and current states or actions and, if available, about plans of the people. People would be able to communicate,
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share information, and work cooperatively independent of the physical location. Seamless integration of information and communication technology in the respective local environment is envisioned. • Pervasive computing: The world is the interface to information
(re)presented via ubiquitous devices (visible and invisiblethat is, embedded in the physical environment). Interaction with information happens in situations, not in specific places. Ubiquitous and interactive landscapes for interaction and cooperation augment reality.
• Device networks: Home and business applications involve device
control networks (user controls devices), device cooperation networks (devices cooperate), quality audio and video networks, and intelligent interactive information and cooperation networks (by smart devices and the intelligent home agent).
• Intelligent home assistance: This would also allow the use of dumb cli-
ents for advanced applications. For example, the TV and hi-fi audio equipment could be used for videoconferences; incoming calls are signaled to the device the user is currently using (e.g., on the TVscreen when the user is watching TV). The home assistant coordinates and manages operations from the background.
Connected devices already exist today, as do device-interconnection technologies. So far, these devices include the medicine cabinet, a combination microwave ovenhome baking terminal, and others. Users can control these devices through their Web pages. Other devices like NetTV successfully use other dumb home devices (NetTV uses the TV screen and the telephone line to access the Internet). Device-interconnection networks are on their way: Industry groups and consortia are currently specifying them and developing demonstration devices. Other related work that tries to accomplish similar things includes pervasive computing, Roomware [77], object-oriented workplace laboratory (OWL) [78], cooperative buildings [79], and intelligent buildings. Jellybeans and the Jellybean Machine
The Jellybean machine (J-machine) is so named because the processors involved are cheap and plentiful like jellybean candies. It is built entirely of a large number of jellybean components. The jellybeans are message-driven
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processor chips with memory, routers, and communication ports for different directions. The routers provide support for automatic routing from source to destination. The J-machine was designed by the MIT Concurrent VLSI Architecture group, which is now located at Stanford University, in conjunction with Intel Corporation. The project was started in 1988 as an experiment in message-passing computing [80]. More than 6 billion jellybeans were in operation in 2000. They are everywherein cars, in TV and radio sets, in cameras, remote controls, and in vending machines. As they become even smaller and cheaper, they will be found in far more places, like in shoes, suits, and possibly in any consumer article. More information can be found in [81]. 3.3.4
Mobile 3G Devices
The beginning of the new millennium coincides with the beginning of wireless access to the Internet for the mass market and the beginning of Internetbased mobile computing. A new breed of devices, specialized and customized, are increasingly coming from the cellular side and are taking up Internet capabilities: the Internet mobile appliance is replacing the PC, which has held the number one position in the computer industry for nearly two decades. Unlike the PC and laptop computer, which are both built for stationary use, mobile appliances free the user to work on the go in ways not possible in the past. Handheld appliances are popping up all over. The PC, in its time, transformed computing by proving that computers could be used for applications other than pure computing. Today, the PC is used far less often as a computing device than as a communication devicecreating text, sending and receiving e-mail, and reading Web pages. This functionality altered the way computers were used, and we see an increasing desire to work with the PC on-line. Notebooks, tablets, and PDAs are devices that emphasize the trend to be independent from a fixed computing environment. In fact, information wanted by the user is no longer seen on the PC but rather on the network. The means of accessing that information is the Web browser, which is turning into the universal graphical user interface. And then there is Java, the object-oriented programming language. It enables the user to transport an application to any Java-compatible system, regardless of the underlying OS. On the market side it seems that desktops and laptopsat least in the United States and some places in Europe and Asiahave reached saturation. Figure 3.38 shows the tendency in shipments of embedded 32/64-bit microprocessors to outpace those of PC processor chips. Other special
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700 Embedded processors
600
PC processors
Units (millions)
500 400 300 200 100 0
2000
2001
Year
2002
2003
Figure 3.38 Shipments of embedded 32- and 64-bit microprocessor chips outpacing PC processors. (Source: [82], 1999 IEEE .)
purpose processors, which are built into mobile phones, cars, and washing machines, are not shown in this diagram. The cellular network side undertook a similar development. It began with voluminous hardware radio equipment for mobile communication in vehicles and households, then evolved into portable mobile telephone equipment and later the mobile phone. All these technology steps were related to one service: voice communications. Over the years, however, additional functionalities around the voice service enriched the mobile phone: telephone directory, short message service, organizer functions like calendar, watchdog, ringing tones selection, language selection, word recognition, voice recording, calculator, games, and MP3 music. Additional services were added with IrDa for connected devices, such as laptops (modem function/PCMCIA), PDAs, and others. Today, we have the smart phone, the smart handheld, the personal communicator, or, combined with the mobile computing, the handheld computer, the mobile organizer, the car organizers, and various other mobile smart devices. The computer industry and the cellular mobile industry now work on merged mobile computing devices, which combine the mobility functions coming from the cellular phone with the computing functions coming from
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the PC, laptop, and PDA. These merged developments lead to newly tailored OSs, new software techniques, new encoding standards, and new programming and markup languages. This evolution in the computer and in the cellular industries places a new emphasis on future developments: • The question of key services and applications becomes a large
valueconnectivity is a main issue.
• Reliability and security are more relevant. • Scalability issues like weight, power consumption and performance,
and costs are increasingly important.
There will be thousands of different device categories customized for special purposes related to TV, road traffic, entertainment, communications, office workers, the household, and so on. As the global standardization on wireless networking progresses, the Internet will be available via a multitude of different wireless access infrastructures, allowing the services to be offered anywhere. There will be single devices related to persons and machines, there will be devices that communicate with each other, and there will be clustered devices, communicating together in their environment, but also externally via a wide area cellular network and via the Internet. Figure 3.39 gives an overview on such communications relations. Related to a person, UC means that that person might interact with many computers at one time, each invisibly embedded in a certain environment. In todays cellular mobile networks, the person usually interacts with a person (mobile telephony) anywhere. Privacy and security play an important role, if it comes to personalized and location-based information services. Combining the servicesmultimedia communication with video, voice, and informationwould allow remote collaboration between persons, and between persons and computers. For example, field workers make repairs more quickly and precisely when they have a remote expert server assisting them. Personal security has to be ensured via identification tags, smart cards, passwords, and public keys. All these criteria will be met with the forthcoming 3G mobile devices, which arrive on the marketplace starting now [43, 83]. Multifaceted handhelds will perform the functions desired by the customer, and the customer will be enabled to tailor those functions to his needs, including the connectivity features necessary for networking. What device categories can be foreseen? All sizes may be possible, from the system
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Wireless WAN Wireless WAN
WLAN, HAN Stationary cluster
Ad hoc WPAN Moving cluster All speeds
Mobile devices
Singles No cluster From stationary to moving All speeds
Figure 3.39 Overview on communications relations.
on a chip up to the handheld, the PDA, the wrist camera, and the mobile computer. The following sections give some indication on what is going to happen in this field. 3G Basic Device Types
The UMTS Forum has chosen five 3G device types for the study period of 2000 to 2010, all with functionality that will enable 3G services (see Table 3.16). These 3G devices will overlap at times, succeed each other in some instances, and decline or evolve in most cases. Each will have its own product life cycle in accordance with a standard product-life-cycle demand curve. 3.3.4.1 The Diversity of Devices Driven by 3G Mobile Developments
Today there is a large diversity of mobile computing devices for many different and device-specific applications: • Super small mobile technology (wrist phones without camera,
mobile keys, lifestyle appliances);
• Handhelds and pocket computers (keyboard-based with or without
pen navigation);
• Organizers;
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3G Laptop Notebook
3G Web Tablet
3G Multimedia Device (Videophone Plus)
Pen, voice
Keypad, voice
Keypad, touchpad, pen
Keypad, pen, touchpad, voice
Like a mobile phone with built-in camera
Small, thin
Becoming smaller, lighter
Magazine-sized (148 × 210 mm), lightweight
Larger than smart phone with keypad smartly built in; camera unobtrusive, video screen small but clear
Power
Low
Low
Medium
Low
Medium
Screen
Uni- to full color
Small, flat, uni- to full color
Full color, high resolution
Full color, flat panel
Full color, small, clear, collapsible screen
Graphics
Basic to full Full
Full
Full
Full
Video
Yes
Yes
Yes
Yes
Yes
Voice
Yes
Yes
Yes
Yes
Yes
Availability
20012005
20022006
2003
2004
20042005
Device Type/ Features
Handheld/ Smart Phone
Personal Digital Assistant
Input
Touchpad, keypad
Form factor
Source: [42].
• Pen-based PDAs and Palm Tops (pen input only); • Smart phones or handhelds; • Smart mobile communication devices; • Special data capture devices; • Pen-based tablets and Web pads, surfpads, e-books; • Notebooks and subnotebooks (mininotebooks); • Special laptops; • Other (car PCs, navigation devices).
This list is certainly not complete, but it shows that different kinds of mobile computing devices already exist for special applications. Pen Computing
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Magazine [84] is a reference for PDAs, pen computers, and mobile computing devices. allNetDevices [85] is another source of news and information about handhelds, smart phones, set-top boxes, and other devices that connect to the Internet. In 2000, mobile devices represented a market of more than 500 million shipments, with expected continued growth. Industry analysts predict that by 2002, more than 100 million wireless computing devices worldwide will be able to tap into the Internet in some fashion. By 2003, analysts predict that nearly 1 billion wireless computing devices and mobile phones will be in use worldwide, 30% to 50% of which will also be using the Internet [86]. The user will have to decide in the future between the smart phone, the PDA, or the pocket computer or notebook. There will not be one optimal and universal device for all kinds of applications. A merger of these device types is not visible today. Super-Small Mobile Technology
Super-small mobile technology is used for very small, special purpose devices. Also belonging to this group are small personal information managers (PIMs) and organizers, frequently called digital diaries, with basic applications like a small calendar, reminder, and address book. Examples are the Franklin REX and REX Pro, Star TAC Mobile Organizer, Seiko Roputer, and Casio Digital Diaries. In the future, such technology will also appear as wrist-phones and wrist video phones, similar to other wrist-watch products. Another example is the Nokia Cardphone, which is a smart cardlike device that substitutes the handheld for a notebook with Windows and MacOS. It has a SIM card slot and antenna and fits into the PCMCIA slot in the notebook or laptop computer. It already achieves high bit rates in 2G networks with HSCSD (34 × 9.6 Kbps). Ericsson offers a similar product, and NTT DoCoMo offers a FOMA computer card for up to 384 Kbps. Handheld (Pocket) Computers
A handheld or pocket computer is a computer that has no keyboard and that can conveniently be stored in a pocket of sufficient size. Todays handheld computers, also called PDAs, can be divided into those with small keyboards and those that use a pen and accept handwriting as input (see the next section). Handheld computers are typically used for advanced organizer types of applications like maintaining schedules, keeping names and phone numbers, doing calculations, taking notes, and, with a modem, exchanging e-mail and getting information from the Web. On the business side, applications
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include portable data collection and automatic data capture with custom handheld devices. The Compaq pocket PC, iPac H3630, is 170g and allows Internet access via GPRS; it is handheld, runs Excel and Internet Explorer, and plays MP3s. It uses Microsoft Windows CE and Linux Mobile as its OSs. Palm OS, EPOC, and Windows CE are the three most widely used OSs in handheld computers. In 2001, Linux was shown as a future possible choice, and Microsoft announced its Stinger platform for smart phones. There are already a number of devices with a color display. A number of companies now combine voice and data communication services using cellular or other wireless technologies with the handheld computer in a single device. Handheld devices include the following models: • Palm devices: 3Com Palm OS (OS); handwritten input; • EPOC devices: Symbians EPOC OS; pen and keyboard input; • CE and Stinger devices: Microsoft Windows CE OS; keyboard and
optional pen input (Stinger smart phones provide a tiny joystick and two buttons for navigation);
• ADC (automated data collection) devices: keyboard and pen input; • Smart phones and two-way pagers: keyboard input.
In the market for handhelds and pocket computers, Palm OS is the leading OS (40%), followed by others (35%), and finally by Windows CE (25%) [87]. Other handheld computers are a little bigger and are designed like little laptops (they are still smaller than subnotebooks): They weigh between 2 and 3.5 lbs, have a 10- to 16-hour battery life, and often run Windows CE. Organizers/Pen-Only PDAs and Palm Tops
PDA is a general term for any small mobile handheld device that provides computing and information storage and retrieval capabilities for personal or business use, often for keeping schedule calendars and address book information. The term handheld computer implies the PDA, which is pen-only. Many people use the name of one of the popular PDA products as a generic term. These include Hewlett-Packards Palmtop and 3Coms Palm Pilot. Most PDAs have an electronically sensitive pad on which handwriting can be received. Apples Newton, which has been withdrawn from the market, was the first widely sold PDA that accepted handwriting. In 2001 and 2002, among the most popular handhelds that accept handwritten input are Palms
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Palm Pilot and the iPAQ H3630 from Compaq. They offer a color display and can be combined with Nokias Cardphone 2.0, which is a PC card developed for notebooks. Typical applications include schedules, address book storage and retrieval, note-keeping, surfing the Internet, and receiving messages. Newer developments are car PCs or car organizers. In 2001 IBM along with a software house introduced the Internet-capable Car-PC in a Porsche Boxter. BMW, Mercedes, and Volkswagen offer similar products. The features include remote control and service support, and in-car control facilities like electronic recording of routes and business communications via GSM/UMTS. Many applications, however, have already been written for PDAs. Increasingly, PDAs are combined with phones and paging systems. Pen-only PDAs and Palm Tops include the following: • Palm OS devices: Palm Inc.s Palm Pilot (connected organizer) [88],
Handspring Visor, Symbol SPT-1500/1700, IBM Workpad, Psion Revo;
• Win CE palm-sized PCs (with color screen): Casio E100 series, Philips
Nino 500, Hewlett-Packards Palmtop Jornada (with color display and 56-Kbps modem) [89], Compaqs Aero 2100 and iPAQ H3630, Siemens SX45;
• Linux devices: The first Linux-driven PDA, using the Agenda Computing VR3 Lux with a high-resolution display of 160 × 240 pixels
and a memory capacity of 8 MB RAM and 16 MB Flash ROM;
• Others: Siemens Unifier IC35, General Magic Data Rover; Pana-
sonic S 10; Epson EHT 40; Fujitsu TeamPad Line; Norand PenKey; Granite Videopad VP7; Royal da Vinci; Casio Pocket Viewers; Texas Instruments Avigo.
This market was led for a number of years by Palm (formerly 3Com) (Palm Pilot), which had 55% market share in 1998, followed by Sharp (19%) [87]. 3Coms newest Palm Pilot, the Palm Pilot VII, has wireless Internet access via 3Coms Palm.Net. Palm.Net uses the BellSouth Wireless Data Network (cellular). Handsprings palm-organizer Visor [90] also runs 3Coms Palm OS, but in contrast to the Palm Pilot, it provides a socket called Springboard for extensions like MP3 players, Bluetooth modules, cellular mobile communication modules, digital cameras, pagers, GPS receivers, chipcard readers, iButton readers, and memory modules. A Bluetooth module and an 8-MB memory module are already available, as well
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as a cellular phone module. Additionally, the Visor is equipped with a microphone. (Smart) Mobile Phones
Many people believe that the key to mobile e-commerce is mobile phones. Already, mobile phones globally outnumber personal computers in unit shipments per year, and they are forecast by some to hit 1 billion units in a couple of years, driving a mass e-commerce market. Durlacher sees the market for mobile e-commerce worth 23 billion euros by 2003, from 300 million in 1998. Having full coverage networks, at least with the next generation of mobile communications, UMTS, smart Internet- and WAP-enabled mobile phones allow one to work and to network anywhere with anybody at any time. Lightweight smart mobile phones like the SL45 from Siemens for GSM are less than 100g, provide organizer functions, SMS, e-mail, WAP access, and MP3 music. For 3G, the mobile phone industry is trying to develop the small personal information assistance device (PIAD) by making mobiles more intelligent and interoperable. By integrating services and features of PDAs and portable access devices (PADs) into their mobile phones, they are trying to take the lead against communication- and internetworking-enabled PDAs and PADs. The latest developments are Bluetooth- and WAP i-mode, FOMA-enabled mobile phones; mobile Internet access is already accomplished. In their early stages, Microsoft and mobile phone manufacturer Ericsson joined forces to offer Web browsers and e-mail over mobile phones, to free the Internet from wires and put it in your pocket. The ubiquity of mobile phones combined with computer technology will deliver mobile e-mail solutions, giving users access to information, personal files, and e-mail from any wireless device. Another agreement is between Casio Japan and Siemens Germany to jointly develop handheld computers with multimedia features, mobile phone capabilities, and Internet access. Mobile Internet communication is growing rapidly in Japan, with electronics makers like Sharp and Citizen producing wireless Internet devices. Casio and Siemens plan to gain 20% of the global wireless Internet device market. The partnership provides Casio with a tie to Europe and gives Siemens additional multimedia technology. The Casio-Siemens SX45 device runs Windows CE and is initially available in Europe. Smart Handheld
Handhelds called handsets are handheld computers or mobile smart phones with an emphasis on voice communication. Terminals (or mobile terminals),
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on the other hand, refer to handheld computers and mobile devices that provide data and voice communication. The major mobile phone manufacturers Nokia, Motorola, Ericsson, and Siemens are developing handsets and terminals with a major emphasis placed on device connectivity. In contrast to nonmobile phone manufacturers, they have significant advantages in terms of interdevice communication and mobility services. Additional devices could be organizers or dedicated devices like Sharps Messenger 500, which is a portable e-mail and WAP terminal. It can be connected to GSM-standard mobile phones. It has a large display and an easy-to-operate keyboard. Traditionally, the mobile phone has been exclusively a device for voice telephony, the paradigm being the PSTN-fixed phone. As GSM networks evolved to deliver new, mobile data-driven applications, users increasingly demanded new functionality on their mobile terminals to enable them to use these new services effectively. Optimized for narrowband communications and offering limited display capabilities, traditional GSM phones were unable to satisfy these demands. The solution was the development and commercialization of smart phones, new GSM terminals with enhanced display capabilities and new features that enabled users to access their e-mail, faxes, and company intranets easily and quickly. The paradigm ceased to be the PSTN phone and became the palm top or laptop computer. Smart phones have larger displays, often a QWERTY or touch-sensitive keypad, and specialized built-in software linked to specific services and applications. It is an advanced mobile phone with additional capabilities that PDAs and handhelds have: a smart personal information assistance device, interoperable, Bluetooth- and WAP-enabled, and with mobile Internet access, Web browsers and e-mail, multimedia capabilities, and enhanced I/O features. Nowadays it is common to have handheld computers with multimedia features, mobile phone capabilities, and Internet access. The distinguishing element is that the primary focus of smart phones is mobile telephone communication, whereas smart handhelds are still personal information managers with telephone and Internet plug-ins. A very important factor for smart phones is the OS that they are running (EPOC and Windows CE are the two important ones; see Section 3.3.4.2.) and the browser that allows the user to surf the Web and process e-mails (Section 3.3.4.3.). It is called a microbrowser, and it will define smart phones and will be the key to taking data to the consumer market. Examples of 2.5G smart handhelds areas follows. The Siemens Smart Handhelds S45, SL45i, and ME45 provide GPRS packet data access in addition to voice, WAP access, a high-resolution
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display, and a number of organizer functions. They are driven by Windows CE and have Java technology. The basic functional set comprises serviceenabling functions for downloading games, restaurant and hotel guides, and so forth, from the Internet. The integrated MP3 player and digital voice recorder allow large storage capacity and synchronization with PC or laptop. Data files can be organized on exchangeable multimedia cards with 16 MB each. For messaging, the new EMS standard is provided, which allows the user to send and receive pictograms, logos, sounds, and the like. The GPRS transport for always-on Internet access is for WAP, the handhelds have a built-in microbrowser. The telephone and address book capacity is for up to 500 addresses or 300 short messages. Intelligent typing is another function to facilitate the generation of e-mails and short messages. Mobile office functions are available with MS-Outlook TM, and PC synchronization SIM Toolkit class 3 is also provided. The size of this device type is 109 × 46 × 20 mm, weighs 93g, with talk time of 100 to 360 min, and standby time of up to 360 hr. The Motorola PDA Accompli 008 looks very similar to a mobile phone. The display has 170 dpi and provides excellent picture quality. It has a Jog-dial for navigations, a little keyboard and handwriting recognition. The Java 2, Micro Edition (J2ME) OS provides a number of features. For PDA operation, the battery lasts up to 10 hr. The Nokia Communicator 9210 is well known and now available as an advanced product with color display and multimedia card extensions. The keyboard is smaller than in subnotebooks. The software allows HTML browsing, short messaging, e-mail, and fax. Ericsson R380 has a monochrome display, works with EPOC, and provides PDA mode and GSM mode. At the end of 2001, Ericsson made the T66 and the T68 with Bluetooth available. T66 is the smallest and lightest mobile phone to date, compact enough to fit into the smallest pocket. It is about the same size as a credit card and weighs only 59g and has a built-in antenna. T68 includes Bluetooth and IrDa, has a color screen, and can download pictures and melodies from the mobile Internet. Both operate in the three frequency bands of GSM. Eclipse from Mitsubishi is a true integration of a pocket PC with a handheld color screen. It uses Windows-CE 3.0 with software like Pocket Office, E-Mail Client, a Web browser, an e-book reader, and AV software. WAP browser, SMS, and telephony are basic features. There is considerable experimentation in form factor while vendors test new product categories. This can be seen especially in the fledgling smart phone market, where an established product form has not yet emerged.
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The term handset refers to 3G mobile phones, in particular mobile devices that allow voice communication, in contrast to terminals, which do not support voice communication. The device weighs around 100g. Smart Pager
A smart pager is an advanced pager with two-way paging (sending and receiving data), e-mail, and Internet access. The smallest pagers might be integrated in watches. Some handheld computer and notebook manufacturers like Apple and Hewlett-Packard plan to offer two-way paging to their palmtop and notebook computers. Special Data Capture Devices
Special data capture devices usually serve specific data capture applications like doing inventory. Current devices typically have a 485 CPU, are keyboard-based, and have a rugged design. They run DOS or other proprietary OSs and are programmed with special proprietary development languages. Pen Tablets
Pen tablets use pens for input but optionally have a keyboard in some cases. They typically serve vertical applications in military and airline industries, for inspections, monitoring, delivery and transport systems, and inventory. Such products are manufactured by IBM, Motorola, Norand, Itronix, Symbol, Panasonic, Ricoh, and many more. Notebooks and Subnotebooks or Mininotebooks
Notebooks are a little bit larger than A4 paper format and are between 2.5- and 6-cm thick. Subnotebooks are small notebooks, they typically run Windows or Linux, they have a weight under 2.5 to 4 lbs., are less than 1-in thick, and have some pen capabilities. Products include Fujitsu Lifebook, Toshiba Libretto and Protégé, Sony Vaio, Sharp Actius, Ricoh Magic, Mitsubishi Amity, Palmax PD-1000, and many more. Their main advantage is compatibility with desktop PCs. Mininotebooks have a smaller keyboard and they weigh less than 2 kg. They usually communicate via IrDA ports with the outside world. Special Laptops
Special laptops have a special design (e.g., a very rugged casing, or an integrated wireless modem). They serve vertical applications in which special design is needed, like for the police (bulletproof), construction (very rugged),
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or hospitals (waterproof). Products include the Amrel Rocky II, Cycomm PCMobile, Itronix, and many more. E-Books
E-books distinguish themselves by their form and application: They are intended for reading manuals and books on a digital device, being able to make annotations and edit papers. Products include the Softbook Press Softbook (9.5-in display, 2.9 lbs, modem, 5-hr battery life), the NuvoMedia Rocket eBook, the Everybook (two screens, with modem), the Cyrix WebPad, the GemBook, and the Glassbook. Ebooknet.com [91] is a reference for e-books. Other Devices PAD This is a portable or desktop-based access device that is used to interact with the environment. PADs can be Internet-enabled, which requires that they support IPs and are attached to some network. Certain PADs may have no direct Internet access and as such use direct-access communication mechanisms (e.g., Infrared, Bluetooth) to access the infrastructure. Such PADs normally bind to a portal to gain access to the services provided via the portal. PADs range from small personal devices (e.g., Swatch Web Wristwatch [92], badges, small handhelds and phones) to more traditional handheld computers (Palm, Windows CE) to full desktop PCs. HP and Swatch collaborated on a device named Web Watch, a watch that stays connected to the Net: The watch is the first of the next-generation context-aware Web devices being developed at HP Labs [72]. Although initially the appliances will require a password or PIN, eventually they will use biometricsfingerprint, iris, voice, or face recognitionto identify the user. They will use GPS or other positioning technology to determine location. And they will contain sensors that will provide information like temperature, light, sound, and motion about the environment. Users control how much information they share about themselves on the Web. Embedded Computers Today there are several embedded computing devices and thin servers (or small Internet servers) available, like the TINI of Texas Instruments [93], the Matchbox Server from Stanfords Prof. Vaughan Pratt [94], and Cell Computings Card PC [95]. Cell Computing manufactures complete single board computers (SBC) that can be used as embedded PCs. Small PC, a division of ICI Controls, Canada, manufactures Rugged Computers for Small Spaces [96].
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Web Appliances These devices support communication via Web-based protocols. A distinguishing feature of a Web appliance is the ability to represent itself via a Web page. A Web appliance can be controlled or accessed using such a Web page from any Web browser. A Web appliance is named and located based on a URL. Examples include Internet-enabled household appliances like the interconnected smart refrigerator [97], the Internetconnected ScreenFridge [98], a Microwave Bank [99], the Internet-enabled washing machine [100], and an AutoPC [101].
As mentioned earlier, in general, the term smart connotes some kind of responsiveness, the ability to react quickly and cleverly to certain circumstances. This also involves the ability to learn. Some manufacturers use the trend-expression smart device to boost the sale of their product. Most of the current devices (e.g., smart fridge, smart washing machine), however, are not truly smart. They have some functionality (like reminders) and they perform programmable tasks corresponding to certain triggers, or even have more advanced functions or features (e.g., accessible via the Internet). But what would make them truly smart is the ability to react cleverly to new situations and to learn from this. This can only be achieved by running intelligent or smart agents on the mobile device, which involves context-awareness and the use of wireless communication for their interaction. Sun Microsystems describes Jini devices as smart devices that establish an impromptu Jini community to interact with each other [102]. The smartness of the Jini device thus builds upon its ability to interact and to establish a community. Those devices are not necessarily smart. Other smart devices are also often promoted in combination with multimedia, Internet, and device-specific services (e.g., smart phone PDAs from Palm).
General Smart Devices
3.3.4.2 Mobile Computing Terminal OSs
An OS is the software program that, after being loaded into the computer by a bootstrap program, controls its operation and directs application processing. Acting as a bridge between the underlying hardware and user applications, the OS provides applications developers with a means to access and manage the available computing resources. Typical functions performed by any modern OS include the following: • Memory management; • Input/output, including such peripherals as the keyboard, mouse,
printer, display, and storage devices;
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• Inform applications or users of operating status and any errors that
occur; • Manage use of the computer among applications competing for its limited resources. In the desktop and laptop world, only a few OSs are in useMicrosoft Windows dominates the world market. For mobile devices, however, many OSs exist, and further, small, simple UC devices may not require an OS. For example, a simple self-powering sensor probably does not need an OS. In fact, the additional overhead introduced by an OS might make the application impractical. In such cases, a small microcontroller coupled with an EEPROM or other memory or storage device would be sufficient. Mobile devices, however, need increasing flexibility to satisfy growing user demand and to cope with the mobile Internet. Real-Time Features Needed?
The term real-time is overused and often misunderstood. Usually, it simply means fast enough. There are, however, academic definitions that prove useful for understanding the space of available products. In general, there are soft real-time and hard real-time systems, but the boundaries are not always clearly defined. For example, the typical Web browser should be responsive to user commands, but if a page takes twice as long to load (say, 2 sec instead of 1 sec) on 10% of visits, this is probably acceptable. When listening to an audio stream, however, losing even 10 ms of audio every 10 sec is probably not acceptable, but failing to meet this requirement is unlikely to have dire consequences. Features that make an OS suitable for use in UC applications are as follows: • Binary or source code compatibility with popular desktop OSs • • • • • •
(Linux, Windows); Support for context awareness; Support for UC-friendly input/output devices; Support for low-power processors and advanced power management standards; Network support; Integration with application-specific hardware devices; Well-supported development environment;
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• Support for programming languages, such as C, C+ +, Jini, and Java; • Support for a wide range of microprocessors.
The UC OS is the piece of software in a device that should optimize the devices resources used, how tasks are scheduled, and how it interfaces with the outside world. Such OSs are designed to handle very stringent real-time operating parameters and often have very different architectures to cope with the demands of their applications. This performance is often at the expense of flexibility. Optimizing the performance, reliability, and resource requirements for cellular-connected devices will be the major challenge for the software industryalthough it will not be the only one. A number of approaches to OS architectures are in use or are emerging, and it is likely that each will find areas where it can outperform rivals. The question will be whether these are sustainable markets. At present, many different OSs in use are competing for market share: • PALM OS; • Windows CE and Microsoft Stinger; • EPOC 32; • Geos; • Linux; • Other (DOS, PenDOS, Data Rover Mobile System, Per-
sonal/Embedded Java).
Palm OS, Windows CE, and EPOC are the most widely used OSs in many kinds of handheld computers, especially in PDAs and mobile phones. New developments like MS Stinger offer integrated Web browsers and push e-mail over mobile phones. The battle for dominance in mobile OSs between Microsofts Windows CE and Symbians EPOC OS will not be affected, as a number of industries will stick to their commitment to the robust, scaleable EPOC OS, which allows the incorporation of applications in their devices. Sun Microsystems tried to position Java as the leading software technology for devices but has had initial difficulty in developing Java into an industrial-strength tool. They divided Java into three distinct dialects to accommodate the differences among mobile devices and information appliances. Personal Java is for networked devices like handheld WebPIMs, smart mobile phones, connected PDAs, WebTV, or games. Embedded Java
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is for devices with limited displays, such as WebPhones, pagers, printers, or fax machines [103]. The third dialect, JavaCard, is for smart-card applications and other very limited devices (e.g., iButton). So far, the two dialects for mobile computing devices are still being evolved. Palm OS
Palm OS is 3Coms computer OS for its PalmPilot computer products. From the beginning, Palm OS was designed to fit into a palm-sized device of a specific size and with a specific display size. These products were designed specifically to act as PC companions. 3Com says that the success of the PalmPilot series can be attributed to this special-focus approach. In contrast to Microsofts Windows CE and Symbians EPOC, which were both designed to serve a broader range of devices, Palm OS is optimized for a particular hardware configurationit operates very well within a set range of tasks, but extending it beyond that is more difficult. Palm OS uses multitasking, but only one task is for applications. The user uses one application at a time: one application program must finish before the next can be selected. This constraint allows the OS to devote full attention to the application that is open. The space needed by the system for any application that is running is kept in dynamic, reusable RAM. The application and its related database are kept in what is called permanent storage, but here the permanent storage is RAM (rather than a hard disk) that cannot be reused like dynamic RAM. Palm OS divides an application into runnable code and different types of data elements, such as user interface elements and icons. The data elements can be easily changed without necessarily having to rewrite code. The upgrade to Palm OS 3.5 includes a mobile Internet kit (MIK) with SMS software, Multimail, WAP browser, and browser for Web-clipping formats. Palm Computing chose not to include a keyboard in the PalmPilot in order to produce a truly palm-sized device. Learning from Apples Newton, an earlier attempt at a pen-and-notepad interface, the company also chose not to provide full handwriting recognition code. Instead, PalmPilot users learn to use a more quickly recognized but restrictive set of pen strokes. These decisions helped keep Palm OS small in size. Palm OS comes with these built-in applications: dates, address book, to-do list, memo pad, calculator, and password protection. New applications can be written and added using several facilities that accelerate development. Palm OS comes with communication interfaces for infrared devices, TCP/IP (for Web connection through wireless or wireline devices) devices,
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GSM devices, and optionally, bar-code recognition scanners. The Palm VII is a connected communicator, working with BellSouths wireless packet data network. The company Handspring licensed Palm OS as a basis for its Visor handheld computer (palm-organizer) and added some enhancements [104]. Symbian EPOC
Symbians EPOC is an OS designed for small, portable computer-telephones with wireless access to phone and other information services. EPOC is based on an earlier OS from Psion, the first major manufacturer of PDAs. The name derived from the companys belief that the world is entering a new epoch of personal convenience [105]. To earlier systems, EPOC adds wireless communication and an architecture for adding application programs. Psion declared its first version of EPOC to be an open OS and licensed it to other equipment makers. The Psion software business was then subsumed in 1998 into a new joint venture called Symbian, formed by Psion, Ericsson, Nokia, and later, Motorola [106]. Symbian licenses EPOC and continues to develop it as the de facto OS for a whole range of mobile devices. Symbian refers to the class of hardware served by EPOC as wireless information devices. EPOC is a 32-bit, multitasking OS that supports a pen-based graphical user interface (GUI). It is written in the C+ + programming language using an object-oriented design. The code is very compact so that it can fit on a small ROM chip. In addition to basic services, the OS comes with an application suite of PIM applications, which includes a word processor, e-mail handler, spreadsheet program, a scheduling application, general purpose database, sketch program, world clock, voice recorder, spell checker, calculator, communication programs, and a Web browser. There is built-in support for rich text, wide characters, color graphics, sound, and embedded objects. It has a modular design, so that licensees can produce devices with their own user interface and applications. EPOC can be scaled from relatively large configurations for a fully functional handheld computer to small configurations for embedded applications. It has a number of features that are specifically aimed at optimizing it for mobile devices, but it also has an architecture that places it in the generic OS space, particularly its portability across a number of hardware profiles and the easy separation of engines, applications, and user interfaces. This combination of attributes is intended to allow uptake of EPOC by a wide range of licensees and developers. Although EPOC can be ported to other microprocessors, Symbians preferred platform is the Advanced RISC Machines (ARM) architecture [107]. Symbian considers ARM the best platform in terms of millions of
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instructions per second (MIPS) per watt and per dollar cost. Symbian provides development kits for C+ + and for OPL, a BASIC-like language. Java support is in beta test. Programmers write programs at a PC and use an emulator to test them. In March 1999, Ericsson announced the first EPOC-based device since the formation of Symbian. Its Mobile Companion, the MC218, is manufactured by Psion and looks similar to the Psion Series 5, but has a built-in custom application suite and infrared connectivity with Ericsson cellular phones. Symbian has also announced a strategic relationship with NTT DoCoMo to create joint research and development programs for devices based on the EPOC platform. EPOC is also already in use in Psions Series 5 handheld computers [105]. Ericsson, Nokia, and Motorola each have a 23.1% stake in Symbian Software; Psions stake is 30.7%. Symbians members are linked to a number of other groups. Symbian supports WAP and Bluetooth. In January 1999, Symbian announced that it had agreed to incorporate STNCs HTML-based microbrowser technology in the EPOC OS. In March 1999, Symbian announced an agreement to incorporate Sun Microsystems Java technology into EPOC. The company also announced a collaborative agreement with Japanese operator NTT DoCoMo to develop smartphones and PDAs for 3G WCDMA networks in Japan [108]. EPOC will compete directly with Windows CE. EPOC, however, is able to exchange data with Microsoft products. Symbian Members
Microsoft Windows CE and Stinger
Microsoft Windows CE OS is based on the Microsoft Windows OS family but is designed for being embedded in mobile memory-constrained devices. Although most of the early deployments of Windows CE have been in pocket computers and cable TV set-top boxes, the company intends to establish it in a wide range of devices (such as in-vehicle terminals and industrial control units). Microsoft does not explain what CE stands for, but it is reported to have originally stood for consumer electronics. Microsofts Stinger was announced in early 2001 as an improved version of Windows CE 3.0 tailored to smart phones. The Stinger platform uses the same basic functionality of Windows CE and the same graphical interface from Windows XP, which is customizable. Windows CE and Stinger compete with EPOC and Palm OS and also with similar OSs from other companies. Like the full-scale Windows
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systems, Windows CE and Stinger are 32-bit multitasking, multithreaded OSs [109]. Linux Mobile
This version of Linux is relatively new and is expected to be successful on the marketplace very soon. It is royalty-free and comes from the Free Standards Group Base Specification. Following efforts by proponents to bring the open-source OS into the mainstream, Linux is increasingly being used in PCs and mobile devices. A group of companies, including Compaq Computer, Hewlett Packard, IBM, and Sun, formed the Gnome Foundation [110]. Its aims are user-friendly interfaces, developer platforms, and applications. It may take some time before Linux can establish a meaningful presence in smaller appliances like palmtops. The new Linux version from Lisa systems [111] was released in 2000 and offers the IT industry mobile applications developments. Sharp uses Linux mobile in its Zaurus PDA with Java as application platform. Compaq uses this as an alternative. Geoworks GEOS
GEOS was developed by the U.S. company Geoworks. It is an objectoriented OS that is intended for use in small devices, such as PDAs and smart phones. Prior to the formation of Symbian, GEOS was the OS used in the Nokia 9000 series communicator. It will not be used in models that appear after the 9110. GEOS is still being used in the Toshiba Genio PCV and has been licensed by NEC and Mitsubishi. The emergence of Symbian has prompted Geoworks to reposition GEOS. It is no longer being targeted purely at the high-end smart phone and communicators market; instead, it is being positioned as the OS of choice for enhanced mobile phones (for example, those that might include a microbrowser but are not as functionally rich as the Nokia 9000 class of device). Geoworks claims that it was planning to reposition GEOS regardless of Symbian, arguing that the market for high-end smart phones will always be very small. 3.3.4.3 Mobile Computing Microbrowsers
The browser implements the customer satisfaction specifiers. Developers specify the browser: how it collects data, how it selects a Web page, cache a page, and so on. Most Internet pages are designed for devices with a minimum 640 × 480 pixel display. This means that when they are displayed on smaller screens (which are commonly found in non-PC devices), these pages
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are less pleasant to view, more difficult to navigate, and are potentially unusable. The amount of information on a single Web page may also be too large to download onto a wireless device quickly, due to network constraints and the memory of the device. For example, i-mode devices with colored displays go up to a maximum of 120 × 120 pixels, which is far less then the minimum for standard Web pages. Development of browsers and content for mobile computing devices are taking place at a rapid pace: Microbrowsers (a Web-browsing technology) and more general client software for wireless access to services [112], which are intended for small mobile handheld computing devices (especially for mobile phones and handsets), are mostly text-only browsers that understand WML and WAP. Web content is delivered in WML format and translated by WAP (see Section 4.5.10). Those technologies have provided an effective catalyst for the development of browsers in mobile phones, but its concentration on the limited display capabilities of basic mobile phones means that even its proponents are looking to additional solutions. The most highly contested ground at the moment is in the mobile computing device market, which WAP was not specifically designed to address. This segment is more suited to browsers that support full HTMLa fact acknowledged by Symbians decision to incorporate STNCs HTML browser into EPOC. But with the use of the Internet on these devices still at a very low level, a clear winner will not emerge until at least 2003. Symbians HTML microbrowser and Microsofts Mobile Explorer show that HTML microbrowsers are one of the most important factors for handsets and smart phones by extending them to multimedia applications. Microbrowser Products
UP.Browser, Mobile Browser WAP Edition, made by Openwave/Phone.com [113], is the most advanced microbrowser. So far, more than 45 wireless phone manufacturers have licensed this browser. More than 70 million units were shipped by early 2001. They are related to WAP Releases 1.0 and 2.0 for 2G and 3G mobile devices. Microsofts Mobile Explorer (MME) browser runs on Windows CE and Stinger handheld devices or smart phones. It also offers SSL and Java capabilities. Microsoft has made an agreement with Samsung, Sony, Hyundai, Benfon, and others to incorporate its microbrowser. It is a dual-mode browser for display of both WAP and HTML on mobile devices. Micro Digitals Graphical MicroBrowser provides embedded systems with a small, yet capable browser that supports HTML4 and Java [114].
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Several more are currently being developed, also by the major mobile phone manufacturers (Nokia, Motorola, Ericsson, Siemens). • EPOCs Opera Browser combines JavaScript and SSL as well as
WAP browsing.
• Nokias WAP browser is developed for its mobile devices like smart
handhelds and its communicator. OEM licenses are available. The microbrowsers are available for the current WAP releases.
• Jataayu WAP browser for PDAs is available for Palm OS, Windows
CE, and EPOC.
• EZOS EZWAP browser is available for Windows NT, CE, and
Windows 2000 platforms.
• J2ME is another offering. A number of industries announced the
integration of J2ME browsers in their mobile devices.
• i-Mode browsers are cHTML-based, using Windows CE. NTT
DoCoMo provides these browsers, which are included in more than 27 million i-mode handhelds and in 3G FDMA smartphones.
The UC Browser Concept
The UC browser concept extends the standard Web user interface for accessing content to local environment-specific resources (e.g. a TV or radio set [115]. The first step towards such a browser is the dual browser recommended by the GSM Association for future WAP services. It shall encompass the markup languages WML 1.2.1 and WML 2.0/XHTML for simultaneous 2G and 3G use in one smart phone. 3.3.4.4 Mobile Computing Middleware
In general, middleware is software, or a software system, that connects separate applications, software entities, or devices and passes data and invocations between them. It mediates between them and enables cooperation. In the field of computer science, middleware is best described by technologies for distributed computing in computer networks like SOAP, CORBA, Java RMI, or Jini. They provide methods and protocols for service- and objectdiscovery, exchange of data, and method invocations. In the field of mobile computing, however, middleware describes a broader range of software systems that both allow collaboration and interoperation and provide basic
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communication. There are two basic middleware types relevant to cellular terminals: • Standardized technologies; • Proprietary product suites.
Mobile middleware (Figure 3.40) is an enabling layer of software to connect applications with (different) mobile networks and OSsto adjust bandwidth, resulting delays, and changes in user location. Middleware gives applications better response times and far better reliability. Typically, middleware uses optimization techniques, such as header compression, delayed acknowledgments, and concatenation of several smaller packets into one, to reduce wireless network traffic. Some middleware supports intelligent restarts, which take the user to the break point after disconnection instead of back to the beginning. Middleware, however, does introduce additional complexity and significant initial cost. Mobile Messaging Support
Mobile-messaging middleware products extend non-IP applications to mobile users. It stores messages when mobile users are out of network range and forwards them later when users are in range. WAP
There are several application protocols for wireless use (HTTP, WSP). Interoperability among different wireless networks, devices, and applications Applications Applications Applications
Middleware Middleware
Wired WiredNetwork network
Mobile Middleware middleware Mobile
Wireless WirelessNetwork network
User devices Figure 3.40 Mobile middleware for application and content adaptation.
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is one of the most important targets. WAP aims to get there. It uses a microbrowser as the client software and supports text, graphics, and standard Web content. A gateway acts as a proxy server for a mobile client, translating WAP requests to protocols employed by the information server on the other side. Encoders translate the content coming from the server into compact formats to reduce the size of data over the wireless network. For other protocols such gateway and filter functions are not available for some other protocols, and in some cases are not even needed, for example in the transparent http access to the Internet and intranets. 3.3.4.5 Jini and Java Devices Jini and Java
Jini technology is an approach to distributed systems that uses several Java properties. In particular, the Jini environment makes heavy use of Java to move objects from one Java environment to another. The mechanisms for using this ability in Jini include a set of conventions for finding services on the network and a means for bootstrapping the system without human intervention. The Jini approach aims to create an environment where network attachment of a wide range of devicesincluding (but not limited to) cellular terminalsis easy and reliable. In January 1999, Sun launched Jini [102], its software technology for spontaneous networking based on the Java programming language. Thirtyseven development partners were announced at the launch, including AOL, IBM, 3Com Palm Computing, Canon, Sony, Ericsson, Motorola, Xerox, and Toshiba. How Jini Works
Jini consists of four program layers: 1. 2. 3. 4.
Directory or lookup service; JavaSpace; Remote method invocation (RMI); Boot, join, and discover protocol.
It is designed to allow devices to attach to networks easily, pulling the software they need across the network and enabling data sharing between devices. Jini-enabled devices can either run a JVM or can be used on the JVM of another machine on the network. This is an approach that is network intensive, but enables devices with even smaller memory resources to
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communicate. JVMs require around 640 Kb of memory. The architecture allows that as long as the device is capable of representing itself as a Java object, it can take part in a Jini community and can use whatever network technology is appropriate for the contextwireless [Bluetooth (Jini sits well with Bluetooth as the service level over the top of a Bluetooth link), WLAN, WPAN, infrared, or cellular] or wired. When a device is plugged into the Jini network, it is immediately registered in the directory service layer as a member of the network. Registration is accomplished by the lookup service: The device locates the lookup service (this procedure is called discovery) and then uploads all of its services interfaces (called joining) to the JavaSpace layer. The lookup service also acts as a switchboard to connect a client with the service it is looking for. When a person, program, or device uses the lookup service to locate a registered device or service (by using the so-called multicast request protocol and the unicast discovery protocol), the interface of the requested service is copied from the JavaSpace layer to the device where it will be used. The actual communication with objects in JavaSpace is done using the RMI interface and layer. The layer supporting the boot, join, and discover protocols enables devices, users, and applications to announce and register themselves and to discover others. Those protocols, as well as the lookup service, depend on the ability to move Java objects between JVMs. This is why Jini requires a TCP/IP network. It is expected that Jini will be used by many mobile computing devices, and at best by all mobile devices [102] and other fixed devices, like household appliances and network computers. Jini is more computing-intensive than WAP and therefore resides more naturally in devices, such as PDAs and handheld computers. Jini is not yet designed for small mobile computing devices. Jini is similar to the middleware technology known as CORBA, but with easy setup and registration processes and dynamic discovery of new services. In contrast to CORBA, its infrastructure is very light and provides only a small set of predefined services: • Java RMI agents; • Lookup and discovery; • Lease services; • Transaction services; • Remote events; • Security.
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Jini allows devices to dynamically establish communication to share and exchange services across a network. The impromptu community is a dynamic environment that eliminates the need for configuring devices or installing drivers. Jini makes it possible to plug printers, storage devices, speakers, and any kind of device directly into a network. Every other computer, device, and user on the network will know that the new device has been added and is available. Each pluggable device defines itself immediately to a network device registry. When someone wants to use or access the resource, his or her computer will be able to download the necessary programming from it to communicate with it. No special device support software (device driver) is necessary for the OS. The OS will know about all accessible devices through the network registry. Jini Devices
The Jini infrastructure is small enough that even the smallest and simplest devices can build a community. Jini-enabled devices need to be equipped with its own small, special-purpose, and possibly microchip-embedded OS that supports a JVM, in order to be plugged into a network and immediately be shared by users and other devices. Mobile devices could be transported and easily plugged into a network so that others could use the device. Of course, Jini-enabled devices must have an IP or other valid network address (IPv6 provides the possibility to address every device on Earth). In the same way that Java technology enables software to run on any device, Jini software enables any device to participate in a networkregardless of the underlying OS of the device or the devices brand. Java
Java is an object-oriented programming language similar to C+ +, but it is platform-independent, which makes it possible to enhance HTML, WML, and XML documents with new functionalities like interactive animation, integrated applications, and 3D models. It is often used for writing applets embedded in Web pages. The Java programming language was developed for a wide range of devices. Meanwhile, several standards focus on families of devices: Java2, Java2 Micro Edition, and Realtime Java. An overview is shown in Figure 3.41. Javas basic philosophy is that the application resides on remote systems, and the resident software in the local system is reduced to limit the memory size and to save resources. When needed, the application software can be downloaded from the network to the users device or local system (see Figure 3.42). To enable downloading into the local system independent
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Communicator PC
Pager
PDA
TV set-top box
Server
Handheld
Laptop Java Java2,2 enterprise Enterprise edition Edition
Java 2, Standard Edition
SIM SIM Card card
Java 2 micro J2MEedition Java language language Java JVM
HotSpot HotSpot Memory
Smart phone
Screen phone
10 Mbyte
KVM KVM*
1 Mbyte 512 Kbyte
*KVM = Kilobyte virtual machine
CVM = Card virtual machine
Figure 3.41 Java.
Application Application Java Java Programs programs Compilation Compilation
Remote system
Java JavaCodes codes
Download Java Javakernel Kernel virtual Machine machine Virtual (Interpreter) (interpreter) Hardware
Figure 3.42 Javabasic design issues.
Network-UICC interface
Local system
Card VM CVM 32 Kbyte
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from the processor and OS, a short instruction set called Java Kernel and Virtual Machine resides in the local system (UICC) to interpret the downloaded application. If this kernel resides in browsers, then, for the download, two methods can be used: smart-card loading (USIM, SIM) or air interface download. The second method provides more flexibility for mobile applications: the user expends no effort, as updating automatically takes place between the users device and the base station, if for example the user roams into another network. The Real-Time Specification for Java (RTSJ) was developed in 2000 as a Java execution environment and API that enables the programming of temporal behavior of execution software. This is important for real-time applications in 3G handhelds and for transport and automation [116]. JavaScript
This is a Web page programming language, whose code is integrated in Web pages. It is an interpreted language, which means that each time a Web page containing Java Script is downloaded, the Web navigator decodes its commands. J2ME
J2ME provides upward scalability with Java standard and enterprise editions. J2ME is targeted at two broad categories of products: mobile phones and stationary devices, such as set-top boxes, Internet TVs, Internet-enabled screen phones, and high-end communicators. J2ME will probably emerge as the default programming language for mobile devices. Motorola has already demonstrated an iDEN phone that includes J2ME applications like games and an Internet message access protocol (IMAP) e-mail client. In 2001, several vendors and operators commenced plans to deliver J2ME phones to the mobile market. A wholly new implementation of the JVM, called the kilobyte virtual machine (KVM), is at the heart of J2ME. Written in C, KVM has a footprint of just 50 to 80 KB, depending on the target platform and configuration options, and runs on 16-bit processors clocked at 25 MHz. Smart phones like the Siemens SL45, the Motorola Accompli 008, and others also provide this platform. 3.3.4.6 Basic Architecture of 3G Mobile Devices
Mobile devices for multimedia applications have to fulfill a number of requirements that did not exist for 2G mobile technologies. Restrictions of mobile handhelds, which are typically battery power, processing capacity, and the display, have to be overcome with new developments (e.g., displays were usually designed to support few gray or color scales with touch screen
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and with screen resolutions ranging from 160 × 160 (UbiNetics GA100) to 640 × 200 pixels (Nokia Communicator 9210) in contrast to 15-inch LCDs with 800 × 600 pixels. The new requirements are described as follows: • The radio interface increases to 5-MHz carrier bandwidth. Small
•
• • •
• • •
carriers (200 kHz for GSM) in second-generation frequency bands need to be supported (multimode-multiband). In addition, the signaling differs between 2G and 3G networks. High-resolution displays (minimum 128 × 128/176 × 200 pixels moving to 240 × 320 pixels) in color and high-performance encoding are needed. IP protocol handling in addition to signaling and security is needed. Multiservice management with Web access (browser), including local applications (organizer functions), needs to be added. For location-dependent services, positioning has to be integrated (e.g., with a GPS receiver) and geographical information has to be stored (which requires high memory capacity). USIM/UICC card reader for management of real-time billing is needed. Voice recognition could be an additional requirement. For AV streaming, buffer memory capacity is required.
These examples show that there may be more customized mobile devices on the market than expected earlier. This is mainly due to the large variety of feature combinations and costs. There are basically two approaches. The Modular Approach This approach builds on the use of two air interfaces or a combination of the 3G air interface with wired or infrared/Bluetooth connections to other devices. In the modular approach, the 3G mobile includes the basic services of voice and SMS and works as a modem for attached devices like laptops, CD-players, and car control devices. There may be also more air interfaces when it comes to multiband mobile devices (e.g., GSM, UMTS, and Bluetooth). The Mobile Multimedia Terminal Approach for 3G/UMTS This approach is an integrated solution tailored to multimedia applications. In addition to basic services like voice and data (modem function), MP3 and MPEG-4 are integral parts of the device. This approach is shown in Figure 3.43.
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Applications module LCD module Display LCD driver
Application software Services
Microbrowser
Java applets
Multimedia processor
mgmt. Power Mgmt.
RAM/ROM Radio Module module
Baseband processing module
Antenna
KERNEL /operating system Charger Charger Reset on/off Power Power supplies supplies Battery
USIM/UICC card
CPU
Timer
Signaling IP protocol control handler
RAM/ROM
UMTS Tx*Tx UMTS GSMGSM Tx Tx GSM/UMTSRc GSM/UMTS Rc
DSP
Channel encoding audio-video External equipment (hands free)
*Tx = Transmitter Rc = Receiver
Figure 3.43 3G mobile device architecture.
The block diagram shows a radio module with the transmit and receive parts for both GSM and UMTS (dual standard for compatibility). The baseband processing module is comprised of the KERNEL, the USIM/UICC card control, a timer, signaling and IP protocol modules based on processor, random access and read-only memory, as well as digital signal processing (DSP). Encoding for voice, audio, and video is another part of the baseband module. Auxiliary equipment includes an external microphone. Power management is optimized for supplying the hardware (depending on the services) and managing the always-on, the sleep, and the active modes. Depending on the number of applications, the applications module includes a number of functionalities. They also could be Java driven and downloaded. Finally, the drivers for the LCD module are shown. Already today, with WAP and Jini, users can call and control Jini objects anywhere on the Web and in the worldfor example, read sensors (temperature, light), turn devices on or off [117], operate connected household appliances, and much more. Another example that has been realized is vending machines, at which soft drinks can be bought via the mobile phone. In the near future, the functionality of mobile phones will be further extended by MExE (to run multiple Java applets internally and Bluetooth for short-range communication without access points; see also Section 3.1.1.1).
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Smart Cards in 3G Mobiles
Smart cards play an important security role in mobile telecommunication systems. They allow the storage of sensitive data, such as user privileges and cryptographic keys, as well as the execution of security algorithms. The use of a removable IC card and a corresponding USIM application is introduced to UMTS. Figure 3.44 shows the main attributes of the USIM/UICC card. The really exciting feature of the USIM/UICC is that the UICC can contain one or more USIM applications, as well as other applications (e.g., for mobile banking). Smart cards in mobile phones authenticate users for network and service access, operate and manipulate menus and services, and are key to mobile e-commerce by offering high security features and mobile computing. The USIM/UICC can be used in GSM or UMTS mobile phones. The SIM Application Toolkit (SAT) or USIM Application Toolkit (USAT) provide a set of commands and procedures that allow applications in the UICC to interact proactively with the mobile phone. In the initial realization of GSM, the SIM card played an essentially passive role, providing the user with the necessary authentication to access the network and storing the GSM encryption algorithms that ensured speech security. It was the users key to the GSM network and contained the users unique network identification information as well as GSM authentication and cipher-key algorithms. This fulfilled the needs of having secure access
Portable
Interoperable cards with different handsets Independent applications from specific MMI Guarantee of the same security level in different environments
Personal
Storage of personal user data to access the GSM and additional mobile networks (roaming) Storage of preferred services One card to access the multiapplication world
Processor
Proactive
Capacity to start a session Offering of ad hoc menus to the handset Bidirectional dialogue with the network
A true PC without a display and keyboard Higher input/output capability New generation of chip based on RISC platform Figure 3.44 Attributes of the USIM/UICC card.
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to the network, deactivating the mobile station when the SIM is removed, and enabling the subscriber to use the SIM in any GSM handset worldwide. Additionally, the user could store personal information on the SIM, such as their personal telephone directory and received short messages, or use it to subscribe to personalized services. Now, with the SAT, the card provides more flexibility. SAT and USAT are standard sets of program tools stored on the chip within the SIM or USIM/UICC card. The tools operate and control the phones menu and allow programming the SIM/USIM/UICC to carry out new functions. These include the ability to manipulate the menu structure of the mobile terminal to provide new, tailored options (for instance, the handset could provide a menu for domestic use and a menu for business use). It also allows outgoing calls to be trapped and number changed, for example when dialing voicemail. These tools, combined with an application-dependent code, can also be used to run remote applications downloaded by the operator and accessed via the phone. The phone becomes personalized to the individual and is thus more user-friendly. The SAT/USAT supports the following: • Profile and data download; • Proactive SIM/USIM, so it can ask the handset to perform certain
functions;
• Bluetooth Protocol support (from USAT); • Menu selection, where the SIM/USIM provides menu items for the
handset to display and registers which one was selected;
• Call control by SIM/USIM; • USIM/UICC provides Java APIs and MultOS API.
A proactive SIM/USIM allows multiapplications to generate powerful menu-driven sequences on the handset, which can interact with services available in the network. Data download allows data or programs received over the short message or cell broadcast services to be transferred directly to the SIM/USIM application. The call control mechanism allows the checking of all dialed numbers and supplementary service control strings before connecting with the network. This provides the ability to allow, bar, or modify the string before the operation commences. The most important component of the SAT/USAT is SMS, which enables two-way communication between the cellular network and the
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SIM/USIM. This means that commands can be sent to and from the network to control the application session. Network operators can remotely provision the users wireless terminal by sending codes embedded in short messages from the server. The use of SAT/USAT enables, for example, the following operatorprovided applications: • Prepaid service activation and control; • Information services; • Directory and hotline services; • Mobile banking and transaction services; • E-mail.
SAT/USAT are designed as client-server applications. On the server side, Orga, Gemplus, and AU-System have introduced servers based on this standard. On the client side, such manufacturers as Siemens, Motorola, Ericsson, Nokia, Bosch, Sagem, and Alcatel have launched phones that support the toolkits. The SIM Toolkit and the WAP are complementary. SAT will be used for applications needing a high degree of security, such as mobile banking, and also for more static information services like hotlines, company directories, and yellow pages. WAP will be used for more dynamic services, such as Internet browsing and accessing changing information services. The use of the USIM/UICC card, however, means relying on a device within a device and working within the restrictions (in terms of memory and processing power) of the card. Thus, continued specifications like APIs on the basis of the UICC card will bring more flexibility, for instance, to enable seamless access to secure value-added services. The increasing technology convergence between computer and telecommunication industries and consumers provides inexpensive and easy-to-use solutions to this challenge. This convergence process will generate major alliances between operators from different economy sectorsfor example, banks are asking the smart-card industry to support multiapplications through cost-effective methods. In this global context, the smart-card market will experience a significant shift from pure vertical segments (banks, mobile, telecommunications, health) toward more horizontal applications (global payment systems, e-commerce, network and multimedia access control, city or national transportation systems). Subsequently, services and solutions will increasingly represent a significant part of the business, as compared with card sales.
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Multiapplications operated over open networks and architectures will require very powerful security management. The electronic purse will be a catalyst in the new market dynamics. Secure, multiapplication smart cards incorporating a purse scheme (mass transit) will act as major boosters for making smart cards a more and more pervasive concept in the global economy. Europes introduction of the euro also contributes to this trend. The enormous economic impact of the Internet and global networks will finally reinforce the role of smart cards as a key entry point for rapidly accessing new services across networks. In this respect, direct user programmability, the ability to download software to the card after issuance, and the availability of industrial standards will be the key leveraging factors [118]. Java Capability The key to Java Smart Cards is their ability to download information. This key ability allows truly personalized smart cards, where the cardholder can choose which applications to load on the card and can change the applications depending on individual circumstances. Most of the USIM/UICC suppliers offer Java applets according to the ISO Java API. 3.3.4.7 Smart Portable Devices in Ad Hoc Networks
Smart portable (handheld) connected devices (appliances) are connected to a WLAN or Bluetooth network, and most of them are also able to interconnect with other devices without the use of the network infrastructure. Some of them might be even smaller and wearable, but those serve very specific applications and are not treated in this section. Smart portable connected devices extend the reach of information to anywhere, anytime, and make people more mobile in their working and leisure tasks. The benefits of the devices are listed as follows: • They are task-centric in nature. • General costs are lower. • Cost of ownership is lower because devices are directed to dedicated
tasks.
• They are supporting tools, not complex machines. • Information is available in any situation at any time without
interruption.
• Typically, the applications are easy to use. • Their use can lead to lower error rates, as compared to manual entry. • They are lightweight, allowing true user mobility.
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Pervasive computing is enabled by the following technologies: • Optimized fixed-function, small form-factor, connected smart
devices (appliances); • Advanced communications infrastructure (WLAN and WAN connections, Internet connectivity); • Integrated databases (yielding transactional integrity, ease of programming, and replication services) on portable devices. Consumers will have PIM assistant devices that store an address book, calendar, reminder, as well as user information to access database information and a unified mailbox (e-mail, voicemail, fax), all operable via a userfriendly graphical user interface. These devices will also be connected to the Internet and will intelligently interoperate and interact with information solutions and services. This development can already be recognized for PDAs, PADs, and smart phones that can access modified services in the Internet and that can control and run specific applications. With the personal device, users will also be able to do e-commerce and mobile e-commerce. They might offer slightly less functionality than 3G mobile phones on the technical side (e.g., availability or coverage and interoperability), but will offer more on the interface side (due to their bigger size and display). Many personal handheld devices store a database of information, which has to be entered separately in each device. In the future, there will be automatic synchronization of the databases and desktop to the smart card for all devices. This simplifies the addition and correction of directory information and allows up-to-date information to be available on the Web or on the handheld device or smart card. In addition, many devices will provide Bluetooth and Jini connectivity. This can allow them to interact wirelessly and spontaneously with other objects and object-networks (e.g., home appliances and entertainment devices, headsets, the car or car components, and so on). Some devices will be smart and context-aware. They can then automatically prepare users for upcoming meetings, actions, and so forth, and equip them with the right information. The handheld device would actually be the platform for a personal intelligent agent. Some devices will also include GPS to provide users with location-specific information and safety services. 3.3.4.8 Devices in Enterprise Applications
Smart devices will unleash a series of valuable enterprise computing and mobile office solutions. Employees will no longer be tethered to their desks,
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and decision-makers can remain empowered even when traveling from site to site. Pervasive computing solutions with information appliances will allow incorporating two-way enterprise access into almost every enterprise area. According to several sources estimates, 137 million business users worldwide work outside of the enterprise and without continuous WAN connections. This might be over soon, and all users will be able to connect to e-business applications and to collaborate in electronic business hubs on the Internet [119, 120]. Enterprise resource planning (ERP) will cover the entire supply chain. Distribution planning, sales planning, forecasting, demand planning, production planning, optimization, work flow, and decision support systems all will be integrated with front-office and back-office execution systems, allowing decision-makers to spot trends and accurately foresee the effects of their decisions. Even automated data capture (ADC) devices hold out tremendous promisebecause ERP supports strategic decision-making, managers often focus on the high-level applications, such as financials, and ignore the input of the raw data. A visit to a warehouse or factory often reveals workers using clipboards, shop tickets, or other paper-based methods to collect data before manually keying it into the ERP system. ADC devices incorporate such features as RFID and LANs, allowing more streamlined and precise data collection. Also, the potential applications for ADC go well beyond factory walls to retail, sales, and other industry sectors. By integrating handheld devices and other pervasive computing technologies, there will be significant cost savings and productivity gains in many areas of information processing. The following are just a few of the benefits that pervasive computing will have to offer: • Broader reach for ERP systems and solutions to all potential users
including employees, partners, and customers;
• Extending enterprise information and infrastructure to this new
class of devices;
• Accurate and timely data for faster, better decision-making; • Lower total cost of ownership for mobile and wireless applications; • Accelerated enterprise application implementations and rollouts; • Effective supply chain management.
A standardized enterprise infrastructure will support the hardware, middleware, and connectivity requirements of those pervasive solutions. This overall integration framework will support all types of applications and will
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emphasize the necessity of seamless communications across todays extraordinarily heterogeneous and geographically dispersed enterprise solutions. Such a system might be implemented by SAP, Oracle Applications, PeopleSoft, J.D. Edwards, or Bahn. Some business application scenarios are shown in Table 3.17. Business processes and supply chain management are increasingly streamlined by the use of information technology. Portable connected appliances are the next level of automating and facilitating business processes. The following list describes how devices and pervasive computing can improve some of the above-mentioned examples: • Sales. An organizations sales force continuously needs customer
information, pricing data, product availability information, and calendars and schedules. Mobile computing devices offer an ideal means for delivering this data in a timely fashion and obtaining up-to-the-minute input from this crucial group of mobile users. • Service. Service personnel require constant customer information updates, including routing information, meter-reading information, order entry records, and parts inventory data. In addition, effective service depends on tracking technicians and monitoring progress, so being able to receive regular data input, including time entries and follow-up requests, is essential. • Plant maintenance. Maintaining equipment information, making safety and trouble-shooting information available at all times, and Table 3.17 Example Business Application Scenarios
Industrial Computing
Customer Relationship Management
Personal-Services and Administration
Advanced data collection
Service management
Procurement
Inventory and warehouse management
Mobile sales and services
Travel-expense tracking and management
Shop floor applications
Cross-application time sheet
Plant maintenance and trouble shooting
Maintenance management
Calendar, tasks, addresses, personal organization
Manufacturing
Production management
Shipping, receiving, and distributing
Transport management
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tracking work orders and requests are basic components of effective plant management. Mobile computing allows technicians and maintenance workers to access the latest information directly from the plant floor, improving their efficiency, ensuring that work is completed in the most timely fashion possible, tracking time and materials as they are used, and maximizing safety. • Warehouse. Warehouse applications require high volumes of data
entry and constant tracking of goods and resources, shipping records, and delivery requests. Often these record-keeping tasks are performed manually using paper-based systems. ADC systems let warehouse workers record receipt of goods so that inventories are immediately updated and goods are issued in a timely fashion. Also, asset tracking, inventory cycle counts, and fixed asset inventory counts can be completed in a more timely and accurate manner.
• Travel expense management and tracking. Mobile computing appli-
cations can allow travelers to record their expenses efficiently, as they occur, ensuring more accurate reporting and permitting effective cost control.
A principal structure of mobile business applications is shown in Table 3.18. Table 3.18 Structuring of Mobile Business Applications M-Commerce Type
Applications Self-Activated
Connection
User-Activated
Transactions: order and Toll ticketing, E-shopping booking, accounting subscription-based paying E-banking
On-line
Digital content delivery
Instant messaging Push e-mail
Information browsing, tourism, directories, sports, weather, salesforce automation
On-line
Telemetry
Status monitoring Interactive marketing Advanced data collection
Remote control Facility management
On-line
Industrial mobile computing
RF applications Service control
Data collection
Off-line
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Smart connected devices can be of great help in crisis management and emergency situations as is the case in police, fire, military, and hospital operations. They would be used for coordination and control of operations and groups, and would also allow real-time information exchange between coordinators and executors. 3.3.5
Devices Summary
Sections 3.3.1 to 3.3.4 describe small information appliances and their technologies: card technologies, iButtons, tag technologies, mobile and UC devices. This section summarizes and compares their key features and attributes. There may be a consolidation of devices in segments where global roaming plays a significant role and where global radio standards have already found wide market acceptance. Device manufacturers want narrow product lines to maintain cost levels, so software has to be compatible with content providers applications offerings. On the other hand, consolidation leads to the tailoring of devices for certain applications. This means that air interfaces, OSs, browsers, and compression software will converge and Java platforms will bring flexibility into this field. Not all appliances, however, can take advantage of these developments. Wearable Small Information Appliances
Their most important benefit is that personal information stays with its owner in an encrypted formthey practically extend the reach of information to anyplace, anywhere, and any time. More intelligent devices may act as intelligent personal agents that may present the right information at the right time. Smart Card and iButton
Their biggest advantages are their enormous security and encryption capabilities due to their computing power and local memory. Small wearable devices can be used for banking transactions, e-commerce, secured transmissions, authentication, and automated identification and data capture. Smart cards will have a great future because of their use in mobile phones and handhelds as well as for mobile payment applications. The iButton has additional advantages in contrast to smart cards: It is very rugged and long lasting, it has more computing and memory power, and it is more secure because it is worn as a closely guarded accessory. As a disadvantage to RF tags, both smart cards and iButtons are read by contact, except for the more expensive contactless smart card. Table 3.19 compares RF tags with smart cards and iButtons.
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Table 3.19 RF Tags and Smart Cards or iButtons
Device
Passive RF Tags
Active RF Tags with RW Memory iButton or Smart Card
Storage
ROM: write once, read many times
RAM: read and write many times
ROM and RAM
Wireless
Touch
Communication Wireless Power supply
External
Internal
External
Computation abilities
None
None
Processor that runs a JVM
Major applications
Identification
Identification, module-specific data (like instructions, attributes)
Identification; storage of personal data; security-relevant personal computation; sensor-equipped iButtons for monitoring status; can upload Java applets, personal preferences and data; encryption; authentication, audit trails, safe transmissions (banking)
Advantages
Wireless; no contact needed; no direct line of sight; no internal power supply needed; passive data capture; parallel rather than serial reading; readability despite dirt, moisture, or other substances that might accumulate on the tag
Wireless; no contact needed; no direct line of sight; passive and active data capture; parallel rather than serial reading; some might have an IC for encryption and computation; readability despite dirt, moisture, or other substances that might accumulate on the tag
IC computing power; rugged; no internal power supply needed; high security: data is encrypted, iButton steel case is secure; durable; personal device for humans; human wears/carries it at all times; security-relevant computation is performed on the personal device only; personal data stays with owner; status-monitoring; has real-time clock; dynamic uploading of data; store any kind of personal information (e-cash, medical, computing environment); safe transmission
Disadvantages
Unsecured; can be monitored; data stored in plain format; not rugged; not durable
Unsecured; data stored in plain format; can be monitored; needs own internal power supply; not rugged, not durable
Touch communication; size: the ring is as big as a piece of jewelry; it is better to wear it on the key fob, the key ring, or the watch; in order to become successful as the ring, it has to be smaller; serial reading
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Tags
All tag technologies are mainly used for automatic identification and data capture, tracking, and instruction purposes. Bar-Code Technologies
Their markets will remain limited to industry and commerce applications, because of the following characteristics: • Ability to read only one bar code at a time; • Necessity for the bar code to be totally exposed in direct line of
sight; • Resistance of bar-code tag to ceverage by dirt, moisture, or other substances; • Requirement that human labor either face the asset properly for scanning or to perform the actual scanning. RFID Tags
RFID tags are plain identification tags with or without rewritable memory for tracking, access, instruction, and data capture purposes. RFID tags have more or less local memory on the tag, depending on the type of application, and come with or without a battery. Their significant advantage over smart cards and iButtons is the noncontact, non-line-of-sight, long-range reading, even through substances like snow, fog, ice, dirt, paint, and crusted grime. They can also be read simultaneously and at remarkable speeds (less than 100 ms). On the other hand, they do not (yet) offer high security and encryption like smart cards and iButtons; but this is not necessary, as tags are used in totally different applications that do not need high security. Tags are used to identify an object or a group of persons, and to grant access to a place or to some information. Smart cards and iButtons are used to securely identify one person and to grant access to personal data only to the one individual. Smart Tags
In the future, smart tags might come with read-write memory and an IC microprocessor to execute some logic and to compute encryption in order to provide authentication and secure transmissions. It will be difficult then to draw the line between them and contactless IC smart cards, which are also one kind of smart tag. Smart cards, however, are more oriented towards authentication, encryption, and personal applications for individuals.
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Applications of smart tags are more oriented towards ID applications for objects and humans, with greater communication ranges, better noise immunity, and higher data transmissions rates. Their application scenarios are specialized applications with proprietary solutions, and tags are customdesigned in different sizes and shapes, depending on the application. Smart cards are standardized in every way of thinking (size, shape, material, power, contact, OS, interface, even applications). Mobile Computing Devices
The growth expectations for mobile computing devices are high. Their forecasts, especially for networked devices, go beyond 2 billion units in 2010. In contrast to other appliances, these devices will be the most powerful and most flexible technologies. They will be comprised ofat least for GSM and UMTSsmart cards with Java support that enables software download from the network. They will converge related to basic hardware and software, but will diverge related to application and use. Mobile computing devices serve many different personal and corporate mobile computing applications, hence so is the variety of available devices. The most popular ones are handheld computers and smart mobile phones. It looks as though they will compete against each other to become the one device of the future. They both want to provide data, voice, and multimedia, but their individual of focus main areas will prevent them from becoming the one universal device. Users will have a set of advanced devices that are optimized for environment and tasks. In 3G it is important for content providers and application developers to know what types of devices are available. The dimension of applications depends on the devices limitations. Battery lifetime and processor performance, memory capacity, and screen size are all determining factors for the applications industry. At this stage, devices can be grouped into the following categories: • Application-specific. The device is optimized for a certain application
(e.g., voice and messaging, entertainment, business). • Modular. The device can be customized with hardware and software for tailoring to certain applications. • All-in-one. The device integrates all hardware and software needed to cover a variety of services. Table 3.20 shows a comparison of such device categories.
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UMTS and Mobile Computing Table 3.20 Mobile Computing Devices Application Areas
Device
User
Services
Business
Consumer Voice/SMS/EMS Focused
Data Focused
Smart phone
++
++
++
+
PDA
++
+
+
++
Laptop
++
++
Web tablet
+
+
All-in-one multimedia communicator
+
+
++
+ In use. ++ Most preferred use.
References [1] Bluetooth SIG, Bluetooth Home Page, http://www.bluetooth.com. [2] Schneidermann, R., Bluetooths Slow Dawn, IEEE Spectrum Magazine, November 2000, Vol. 37, No.11, pp. 6165. [3] Fun Communications Germany, http://www.fun.de. [4] Dutta-Roy, A., Networks for Homes, IEEE Spectrum Magazine, December 1999, Vol. 36, No.12, pp. 2633. [5] HomeRF Working Group, http://www.homerf.org. [6] HomeRF Working Group, SWAP white paper, The Shared Wireless Access Protocol (SWAP), http://www.homerf.org/press/hrfwgmkt.pdf. [7] DECT Forum, http://www.dect.ch, and Ericsson, DECT Overview, http:// www.ericsson.com/BN/dect.html. [8] Ahlers, E., and P. M. Ziegler, LuftbrückenUSB-Adapter und Basisstationen für die Funkvernetzung, ct magazine, Vol. 18, 2001, pp. 126133. [9] Urban, J., et al., BRAINAn Architecture for a Broadband Radio Access Network of the Next Generation, Wireless Communications & Mobile Computing Magazine, Vol. 1, No.1, JanuaryMarch 2001, pp. 5575. [10] Aironet Wireless Communications, http://www.aironet.com. [11] Lucent Technologies, Orinoco, http://www.wavelan.com.
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[12] Proxim, http://www.proxim.com, and MobileStar Network, http://www.mobilestar.com. [13] Intermec Technologies, Wireless LAN products, http://www.intermec.com/ local_area/wireless.htm. [14] Nokia, http://www.nokia.com. [15] Symbol Technologies, http://www.symbol.com. [16] WebGear, Inc., Wireless Networking Products, http://www.webgear.com. [17] Z-Com, Inc., Wireless Networking Company, http://wwww.zcom.com.tw. [18] Hillebrand, F., GSM and UMTS: The Creation of Global Mobile Communications, London: John Wiley & Sons, 2001. [19] Eberspächer, J., H. J. Vögel, and T. U. München, GSM Global System for Mobile Communication, Stuttgart: B. G. Teubner Verlag, 1999. [20] Sarikaya, B., University of Aizu, Packet Mode in Wireless Networks Overview of Transition to Third Generation, IEEE Communications Magazine, Vol. 38, No. 9, September 2000, pp. 164172. [21] IEEE, IEEE 802.16 Broadband Wireless Access (BWA) Standard, http:// www.grouper.IEEE.org/groups/802/16. [22] Ortiz, S., Jr., Broadband Fixed Wireless Travels the Last Mile, IEEE Computer Magazine, Vol. 33, No. 7, July 2000, pp. 1821. [23] Prasad, R., W. Mohr, and W. Konhäuser, Third Generation Mobile Communication Systems, Norwood, MA: Artech House, 1999. [24] International Telecommunication Union, Radio Communication Study Groups, ITU-R Recommendation, Document M.1457, September 12, 2000. [25] UMTS Forum, UMTS Forum Report No. 1, A Regulatory Framework for UMTS, 1012 Russel Square, London WC1B5EE, United Kingdom, UMTS Forum, October 1997. [26] Ruggieri, M., (ed.), Mobile and Personal Satellite Communication 3, Proc. European Workshop on Mobile Personal Satcoms (EMPS98), London: Springer Verlag, 1999. [27] Iridium, LLC, http://www.iridium.com. [28] Globalstar, http://www.globalstar.com. [29] American Mobile Satellite Corporation, http://www.AmMobile.com and http:// www.satphone.net/skymain.htm. [30] OmniTRACS, http://www.qualcomm.com. [31] Comsat Corporation, http://www.comsat.com. [32] GPS Antennen, http://www.gps-antenna.de.
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[33] Holux Technologies, Inc., Taiwan, http://www.holux.com.tw. [34] Infrared Data Association, http://www.irda.org. [35] UMTS Forum, http://www.umts-forum.org; and UMTS Forum, UMTS Forum Report No. 1, A Regulatory Framework for UMTS, 1012 Russel Square, London WC1B5EE, United Kingdom, UMTS Forum, 1997, http://wwww.umtsforum.org/reports.html. [36] UMTS Forum, UMTS Forum Report No. 10, Shaping the Mobile Multimedia Future, 1012 Russel Square, London WC1B5EE, United Kingdom, UMTS Forum, October 2000. [37] UMTS Forum, UMTS Forum Report No. 12, Naming, Addressing and Identification Issues for UMTS, 1012 Russel Square, London WC1B5EE, United Kingdom, UMTS Forum, January 2001. [38] Telephone Traffic Theory, Tables and Charts, Third Edition, Berlin: Siemens AG, 1981. [39] UMTS Forum, UMTS Forum Report No. 6, UMTS/IMT-2000 Spectrum, Appendixes 1 to 3,1012 Russel Square, London WC1B5EE, United Kingdom, UMTS Forum, December 1998. [40] Andrisano, O., R. Verdone, and M. Nakagawa, Intelligent Transport Systems: The Role of Third Generation Networks, IEEE Communications Magazine, Vol. 38, No. 9, September 2000, pp. 14451. [41] UMTS Forum, UMTS Forum Report No. 5, Minimum Spectrum Demand per Public Terrestrial UMTS Operator in the Initial Phase, 1012 Russel Square, London WC1B5EE, United Kingdom, UMTS Forum, September 1998. [42] UMTS Forum, UMTS Forum Report No. 9, 13, The UMTS Third Generation MarketStructuring the Service Revenue Opportunities, Parts I, II, 1012 Russel Square, London WC1B5EE, United Kingdom, UMTS Forum, October and April 2001. [43] UMTS Forum, UMTS Forum Report No. 15, Key Components for 3G Devices, 1012 Russel Square, London WC1B5EE, United Kingdom, UMTS Forum, December 2001. [44] Gartner Group, http://www.gartner.com. [45] France Telecom, http://www.francetelecom.fr. [46] AIM Global, Magnetic Stripe, http://www.aimglobal.org/technologies. [47] Compaq Computer Corporation, http://www.compaq.com. [48] Hewlett-Packard, http://www.hp.com. [49] Bull Corporate, http://www.bull.com; Bull, Smart Card and Terminals, http:// www.cp8.bull.net. [50] Gemplus, http://www.Gemplus.com.
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[51] Giesecke & Devrient, http://www.gdm.de. [52] Schlumberger, http://www.Schlumberger.com. [53] OpenCard Consortium, OpenCard FrameworkGeneral Information Web Document, Second Edition, October 1998, http://www.opencard.org/docs/gim/ ocfgim.pdf. [54] Visa Executive Vice President Mike Beindorff, at Sun Microsystems, http:// java.sun.com/features/1998/01/keynote.story.html. [55] Gemplus, http://wwww.gemplus.com. [56] AIM Global, Dye Diffusion Thermal Transfer, http://www.aimglobal.org/technologies/card/d2t2.htm. [57] AIM Global, Common Applications, http://www.aimglobal.org/technologies/card/ card_applications.htm. [58] Dallas Semiconductor, iButton Home Page, http://www.iButton.com. [59] Dallas Semiconductor, Digital Jewelry, http://www.iButton.com/store. [60] Dallas Semiconductor, iButton Applications, http://www.iButton.com/applications. [61] AIM Global, Barcode, October 1999, http://www.aimglobal.org/technologies/ barcode. [62] Uniform Code Council, Inc., UUC Homepage, http://www.uc-council.org. [63] AIM International white paper, version 1.1, 07/1998, Radio Frequency Identi- ficationRFIDA Basic Primer, http://www.aimglobal.org/technologies/rfid/ resources/papers/rfid_basics_primer.htm. [64] AIM Global, Electronic Article Surveillance (EAS), An Overview of the Major Technologies, http://www.aimglobal.org/technologies/eas/easoverview.htm. [65] Barba A. Pier,RFID Standards Update, Intermec Technologies, http://www.intermec.com, August 1999. [66] AIM Global, Common Applications, http://www.aimglobal.org/technologies/rfid/ common_applications_rfid.asp. [67] Transintel, http://www.transintel.com. [68] Savi Technology, http://www.savi.com. [69] ID Micro, http://www.idmicro.com. [70] Applied Digital Solutions, Inc., Digital Angel, http://www.adsx.com, and Applied Digital Solutions, Inc., Digital Angel Website, http://www.digitalangel.net. [71] Virginia Smart Travel Service, Smart Tag, http://www.smart-tag.com. [72] Hewlett-Packard Labs Worldwide, http://www.hpl.hp.com. [73] Hewlett-Packard Labs Worldwide, CoolTownWeb Appliances and E-Services, http://cooltown.hp.com.
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[74] Indala Corporation, BiStatix Whitepaper, http://www.mot.com/LMPS/Indala/bistatix.htm. [75] Tangible Media Group, MIT Media Lab, http://tangible.www.media.mit.edu/ groups/tangible. [76] Higgins, K. J., Digital Certificates: Take on a New E-Dentity, InternetWeek, No. 793, December 1999, p. 51, http://www.internetwk.com/indepth/indepth121399.htm. [77] Streitz, N. A., J. Geißler, and T. Holmer, Roomware for Cooperative Buildings: Integrated Design of Architectural Spaces and Information Spaces, Proc. Int. Workshop on Cooperative Buildings (CoBuild98 ), Darmstadt, Germany, February 1998. [78] Brügge, B., R. Pfleghar, and T. Reicher, OWL: An Object-Oriented Framework for Intelligent Home and Office Applications, Proc. Second Int. Workshop on Cooperative Buildings, (CoBuild99), October 1999 http://jupiter.informatik.tu-muenchen.de/ projects/OWL. [79] Second International Workshop on Cooperative Buildings (CoBuild99), http:// www.cs.cmu.edu/~CoBuild99, October 1999. [80] The Jellybean Machine, Web page, http://www.cva.stanford.edu/j-machine/ cva_j_machine.html. [81] Tvede, L., and P. Ohnemus, Marketing Strategies for the New Economy, Sussex, United Kingdom: John Wiley & Sons, Ltd., 2001. [82] Hennessy, J., The Future of Systems Research, IEEE Computer Magazine, Vol. 32, No. 8, August 1999, p. 30. [83] UMTS Forum, UMTS Forum Report No. 11, Enabling UMTS/Third Generation Services and Applications, 1012 Russel Square, London WC1B5EE, United Kingdom, UMTS Forum, October 2000. [84] Pen Computing Magazine, http://pencomputing.com. [85] allNetDevices, allNetDevicesNothing but Net Devices, http://www.allnetdevices.com. [86] Ovum, Ovum On-line, http://www.ovum.com. [87] Gartner, Inc., Operating Systems/Control Programs, September 18, 2001; http://www.gartner.com. [88] Palm, Inc., 3Com Palm Computing, http://palmpilot.3com.com. [89] Hewlett Packard, HP Jornada PC Companions, http://www.hp.com/jornada. [90] Handspring, http://www.handspring.com. [91] Ebooknet.com, http://www.ebooknet.com. [92] Swatch AG, http://www.swatch.com.
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[93] Texas Instruments, TINI, http://www.iButton.com/TINI. [94] Pratt, V., Matchbox Server, http://wearables.stanford.edu. [95] Cell Computing, http://www.cellcomputing.com. [96] Small PC, http://www.smallpc.com. [97] Southport Retravision, http://www.southport-retravision.com.au. [98] Electrolux, Inc., Electrolux Screen Fridge, http://www.wired.com/news/news/email/ explode-infobeat/technology/story/17894.html, 1999. [99] NCR Corporation, NCR microwave bank announcement, http://www.wired.com/ news/technology/story/14949.html, 1999. [100] Margherita2000, http://www.margherita2000.com/sito_uk/it/home.htm. [101] Clarion Corporation, AutoPC, http://www.autopc.com/walkthrough/communication, 1999. [102] Sun Microsystems, JINI Connection Technology, http://www.sun.com/jini, and The Jini Community, http://www.jini.org. [103] Sun Microsystems, PersonalJava Technology White Paper, http://java.sun.com/ products/personaljava/pj_white.pdf, August 1998. [104] Handspring, Visor and Visor Deluxe, http://www.handspring.com/products/ vindex.asp. [105] Psion PLC, http://www.psion.com. [106] Symbian, http://www.symbian.com, July 2001. [107] ARM, Ltd., http://www.arm.com, October 2000. [108] Ovum Report, Wireless Internet: New Frontiers for Cellular Terminals, http:// www.ovum.com/default.htm?dDirect=sample/wireless_internet.htm, July 2000. [109] Microsoft, Windows CE Homepage, http://www.microsoft.com/windowsce. [110] GNU Network Object Model Environment, http://www.gnome.org. [111] Lisa, http://www.lisa.de, 2001. [112] WAP Forum Frequently Asked Questions, http://www.wapforum.org/faqs, August 2001. [113] Phone.Com, http://www.phone.com. [114] Micro Digital, Inc., Graphical MicroBrowser, http://www.smxinfo.com/rtos/tcpip/ gmbpb.htm. [115] Beigel, M., et al., User Interfaces for AII, The Ubicomp Browser, Stockholm, Sweden, Telecooperation Office, University of Karlsruhe, October 1998.
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[116] Bollela, G., and J. Gosling, The Real-Time Specification for Java, IEEE Computer Magazine, June 2000, pp. 4754. [117] Wireless IT 99, November 24, 1999, Santa Clara, California, United States. Bill Joy, Sun Microsystems, successfully demonstrated the control of remote Jini services through the Internet by a WAP-enabled mobile phone. [118] Tual, J.-P., MASSC: A Generic Architecture for Multiapplication Smart Cards, IEEE Micro, Vol. 19, No. 5, September/October 1999, pp. 5261. [119] SAP, SAP E-Business Solutions, http://www.sap.com/index.htm. [120] Hofmann, M., Pervasive Computing Introduction, Pervasive Computing, SAP AG, http://www.sap.com/solutions/technology/pdf/bfa_pc003.pdf.
4 Standardization The ability to communicate, network, and cooperate is essential for UC devices. Chapter 3 approached this subject from a technological point of view and described technologies for mobile communication links between devices, and mobile wireless networks as communication infrastructures. It dealt with the techniques and physics that allow the act of communication. It was established that protocols, format conversion, and software are what allow the desired cooperation, whereby specified standards are essential for implementation. This chapter gives an overview on standards, which are involved in mobile computing and UMTS. Standards have to be considered in the following areas: • Networking and connectivity; • Registration and addressing; • Protocols and software, computer languages, and distributed archi-
tecture; • Format conversion and compression techniques.
Standards for ubiquitous and mobile computing are driven forward by national and international standardization organizations, by industry alliances, and by international forums. On the global level, we find the international standardization organizations in the data and media worldfor 241
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example, ISO, IEC, the ITU, and the Global Partnership Projects, which are formed by regional and national standardization bodies. The IETF [1] is another organization with a global focus; however, it was not legally established in the way traditional bodies work. Internationally, we also find a variety of industry alliances depending on specific standardization targets. Examples are the WAP Forum, the HIPERLAN12 Global Forum, and the Bluetooth Special Interest Group. Finally, there are the regional and national standardization institutes, which differ in their membership size and structure. In the United States, the American National Standardization Institute (ANSI; http://www.ansi.org) plays an important role with its suborganizations dealing with wireless communications (e.g., TIA, T1P1). In Europe, the European standardization institute ETSI has global membership and has driven standards of global value (most notably GSM). CEN CENELEC cares about data standards. In Japan there are ARIB and TTC, in Korea TTA, and in China CWTS, which was founded in 1999 (see Figure 3.8). For UC, standardizations on a global basis are of fundamental importance, and even more so for mobile cellular systems because of the need for worldwide roaming. Thus, standardization is a key issue for IMT-2000/ UMTS. There already exists in this field the tradition to coordinate and define the framework standards for global wireline and wireless access, for national and international telecoms infrastructures on the ITU level, and on the regional and national level, the specifications developments for product implementation. Also, the standards for the mobile Internet have to be global. The fixed Internet standards, with their roots in the development of the ARPANET and in the LAN area, evolved to a global standard with the worldwide use of the Internet protocols in PCs and computers. IETF, W3C, ICANN, and other IP-related standards organizations are working to develop them towards mobile applications (mobile IP). These standards will be merged for UMTS in the 3GPP. In addition, for data processing, data communications, television, and multimedia, ISO, IEC, and ITC standards were developed and continue to be valid for all kinds of data and multimedia applications and services. Mapping Internet content to mobile wireless devices requires new standards and innovative solutions that minimize cost and maximize efficiency. The mobile Internet must deliver information in a suitable format to handheld devices, regardless of location and content. The wireless access has already introduced a new set of standards and protocols that add a layer
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of complication to applications not necessarily compatible with the Internet (e.g., the GSM/GPRS standard and the i-mode standard from NTT DoCoMo). For UMTS these standards have to be supplemented for those services that will also be offered on the wireline network. The harmonization of the terminal interworking characteristics between wireless and wireline terminals may also be a standardization issue. Standardization furthermore has to specify impacts regarding addressing, which is quite different in telecommunications than in the IP world. The harmonization of the UMTS standards in the IMT-2000 framework with the standards on the Internet side is necessary to make mobile multimedia happen in an international networking environment, especially for roaming use. The role of the UMTS Forum [2], the IPv6 Forum [3], the UWCC [4], and other market representation partners within 3GPP is to widen the scope of the standardization and to convert its views into requirements and work items. An overview of standards that are relevant for UC is shown in Figure 4.1. The individual members of these standardization bodies and forums come from the application service industry, the equipment manufacturers, the network operators, and Internet service providers, from software companies, smart-card industries, regulators, and universities. In addition, as multimedia and mobility applications lead the way forward, other industries like the media and the automobile industry are joining these activities.
4.1 WPAN and WLAN Standardization Various industry groups and standardization organizations deal with the standards in this field. The main bodies in the wireless sector are IEEE, ETSI, special interest groups like the BSIG, and forums like the H2GF. 4.1.1
Bluetooth
BSIG was established to create this global specification for a wireless communications interface and control software, in order to ensure device interoperability. Bluetooth is an open industry specification that will be made available to BSIG members on a royalty-free basis. The growing momentum behind Bluetooth is indicated by the fact that the SIG recently enrolled its 2,000th member company. Many of the Bluetooth application scenarios compete with the popular IrDA standard for infrared data communications. Bluetooth supporters dream of mobile phones in the briefcase that forward incoming e-mails via
Software CORBA API JAVA JINI J2ME SOAP
Encoding Encoding
Addressing Addressing Copyright Copyright
AMR Compression JPEG MPEG2 MP3 MPEG4 MPEG7 T.120 H.261/263 H.323/324
Billing Billing
W3C IEO/JTC1 WAP Forum VXML Forum
3GPP ITU/ETSI/ ANSI IETF
3GPP ITU/ETSI/ ANSI/ARIB IETF
3GPP ITU/ETSI/ ANSI/ARIB IETF
Mark -up Markup Languages languages
Protocols Protocols
Devices / Devices/ Smart Cards smart cards
WAN WAN
HTML
IPv4/v6 IPv4/v6 Internet
WML XML
Security Security Keys keys
XHTML CXML VXML
e-Commerce E-commerce
PML
IS-95, IS-136 GSM IMT-2000 UMTS DVB, DAB PSTN ISDN
SIM, USIM X.509 ETSI/ EPSCP Human machine interfaces* ISO 9241 ISO 14915, 11581, 13714 ISO/IEG11580 *www.iso.ch
Figure 4.1 Overview of relevant standards for UC.
GSM IS-95 CDMA 2000 WCDMA UTRA FDD TDD
JTC1 ISO IEC ITU/ETSI/ IEEE H2GF BSIG LANs, LANs,PAN, PAN, HAN HAN Bluetooth WLAN 302.1x HIPERLAN HAVi UPnP HPnP OSGI DECT
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Software Software APIs APIs
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IETF IEEE OMG
ISO JTC1 IEC (ITU/ETSI/ ANSI)
W3C ICANN JTC1 ISO IEC ITU/ETSI/ ANSI GSM A
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the Bluetooth adapter to the notebook on the conference table; they envision handhelds communicating with mobile and stationary PCs and headsets connecting wirelessly to a mobile phone for wireless, hands-free calling. 4.1.2
IEEE 802.X Standards
Technologies for physical media access by wireless follow several specifications (Table 3.4), some of which have been approved by independent standards bodies. One such suite of specifications is IEEE 802.11. In conformity with U.S. Federal Communications Commission (FCC) requirements for the use of the unlicensed ISM band, IEEE 802.11 allows both direct sequence (DS) and frequency hopping (FH) spread spectrum. (The debate as to the superiority of DS versus FH is highly technical and ongoing.) The maximum data rate offered by the standard for either technique is 2 Mbps. However, a higher bit-rate version of IEEE 802.11 allows a data rate of up to 11 Mbps. A drawback of the 802.11 protocol for data transfer in a home network is its high overhead. IEEE 802 LAN/MAN Standards Committee [5] develops LAN and MAN standards, as well as one WPAN standard (802.15). The IEEE P802.15 Working Group on Wireless Personal Area Networks is a standardization project between the two initiatives Bluetooth and HomeRF. The most widely used standards are for LANs, like the Ethernet family, token ring, wireless, bridging, and virtual bridged LANs. IEEE 802.15 Wireless PAN Standard
The IEEE P802 LAN/MAN Standards Committee designated the P802.15 Working Group on WPANs. The standards created by P802.15 will address the requirements for wireless personal area networking of PCs, PDAs, peripherals, cell phones, pagers, and consumer electronic devices to communicate and interoperate with one another. There are four task groups (TGs): TG1 for the physical and MAC layer, TG2 for coexistence issues, TG3 for high bit rate improvements up to 20 Mbps, and TG4 for low data rate devices and connectivity. The standard addresses the following issues in particular [6, 7]: • Worldwide spectrum allocations for unlicensed bands, such as
2.4 GHz (ISM band 2.42.483,5 GHz);
• Allowing coexistence of multiple WPANs in the same area (20
within 400 ft2);
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• Allowing coexistence of multiple wireless systems, such as IEEE
802.11 in the same area;
• WPAN network access control (ad hoc networking); • A range of 0 to 10m; • Networking support for a minimum of 16 devices; • Attaching within 1 sec, once within range; • Addressing QoS to support a variety of traffic types; • Connectionless and connection-oriented links.
In comparison to Bluetooth and HomeRF, IEEE 802 focuses only on the lower layers of the ISO/OSI Reference Model. IEEE 802.11 Wireless LAN Standard
The IEEE 802.11 Wireless LAN Standard [8] ensures that users can purchase interoperable products from a number of vendors to configure and expand wireless local area computer networks. It was created in 1990 and has had a difficult start: many years passed before agreement was achieved on the first version of the standard providing 1- or 2-Mbps bit rates. The standard also included two incompatible approaches, frequency hopping and direct sequence, which led to incompatible products. Today, IEEE 802.11 is well established, thanks to the ratification of IEEE 802.11b. Its advantages over other WLANs lie in the global ISM band. The establishment of the Wireless Ethernet Compatibility Alliance (WECA) with 51 companies worldwide was a deciding factor (its members include Nokia, 3Com, Lucent, Aironet, Symbol Technologies, and many more). WECA promotes IEEE 802.11 under the brand WiFi, the standard for wireless fidelity. WECA conducts tests to ensure product compatibility of different vendors. The IEEE 802.11 standard specifies the physical and MAC layers for WLANs. There are six 802.11 standard sets: 1. 802.11a: 5-GHz band via orthogonal frequency division multiplex (OFDM); 2. 802.11b: 2.4-GHz band, DSSS physical layer, and data transfer rates between 5.5 and 11 Mbps; 3. 802.11d: defines physical requirements (channelization, hopping, patterns, new values for current MIB attributes) to extend into new regulatory domains (countries);
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4. 802.11e: enhancements to support LAN applications with QOS, security, and authentication requirements, such as voice, media streams, and videoconferencing; 5. 802.11f: recommended practices for multivendor access point interoperability via interaccess point control (IAPP) access distribution systems support 802.11; 6. 802.11g: use of DSSS to 20 Mbps+ and OFDM to 54 Mbps. This will be backward compatible with 802.11b and extend it to rates greater than 20 Mbps. This will improve access to fixed LANs and internetwork infrastructure (including other WLANs) via access points as well as ad hoc networks. Of these, three have been ratified: 802.11, 802.11a, and 802.11b. Protocol for Two Types of Networks
The IEEE 802.11 standard defines the protocol for two types of networks: ad hoc and client-server networks. An ad hoc network is a simple network where communications are established between multiple stations in a given coverage area without the use of an access point or server. The standard specifies the etiquette that each station must observe so that they all have fair access to the wireless media. It provides methods for arbitrating requests to use the media to ensure that throughput is maximized for all of the users in the base service set. 802.11 Wireless LAN Standard Physical Layer Implementation Choices
The physical layer in any network defines the modulation and signaling characteristics for the transmission of data. At the physical layer, two radio transmission methods and one infrared are defined. Operation of the WLAN in unlicensed frequency bands requires the spread spectrum modulation to meet the requirements for operation in most countries. The radio transmission techniques in the standard are frequency hopping and direct sequence spread spectrum. Both architectures are defined for operation in the 2.4-GHz (unlicensed ISM) frequency band. Each occupies 83 MHz of bandwidth ranging from 2.400 to 2.483 GHz. The radiated power at the antenna is set by the rules governed by FCC part 15 for operation in the United States. Antenna gain is also limited to a 6-dBi maximum. Power is set low because the unlicensed frequency bands, and many small systems, including household appliances like the microwave oven, are using these bands, which may cause a lot of possible interference. That is also why they put much
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effort in anticollision protocols. The radiated power is limited to 1W for the United States, 10 mW per 1 MHz in Europe, and 10 mW for Japan. There are different frequencies approved for use in Japan, the United States, and Europe, and any WLAN product must meet the requirements for the country in which it is sold. Reference [8] gives details of the different frequency allocations for unlicensed operation in Europe, Japan, and the United States. The physical layer data rate for FHSS and DSSS systems is 1 and 2 Mbps, respectively. The extension 802.11b of the standard, however, specifies 11 Mbps. There are a variety of analyses that support the superiority of each modulation method. The choice between FHSS and DSSS will depend on a number of factors related to the user application and the environment that the system will be operating. One infrared standard from the Infrared Data Association (IrDA) operates in the 850- to 950-nm band with peak power of 2W. The modulation for infrared is accomplished using either 4- or 16-level pulse-positioning modulation. The physical layer supports two data rates: 115.2 Kbps and 4 Mbps (FIrDA), and in the future will support 16 Mbps (VFIR). 802.11 Wireless LAN MAC Layer Specification
The 802.11 Wireless LAN MAC layer specification has similarities to the 802.3 Ethernet wired line standard. The protocol for 802.11 uses a protocol scheme known as carrier-sense multiple access with collision avoidance (CSMA/CA). This protocol avoids collisions instead of detecting a collision like the algorithm used in 802.3. It is difficult to detect collisions in a RF transmission network, and it is for this reason that collision avoidance is used. The standard further includes an encryption method, the wired equivalent privacy algorithm, power management, and a basic framework for roaming. Seamless roaming, the ability to move from wireless cell to wireless cell while remaining connected to the home networks services, provides complete mobility and flexibility in the LAN. The IEEE 802.11 WLAN standard is one of the first generations of standardization for WLAN networks. The interoperability between WLAN equipment manufacturers is key to the success of the standard. Interoperable products are mainly implemented on PCMCIA cards for use in applications for handheld personal computers, PDAs, laptops, or desktops. The Wireless LAN Interoperability Forums OpenAir Specification
As an alternative or precursor to the IEEE 802.11 standard, a multivendor forum, the WLIF [9], has been established to specifically address the issues of
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WLAN interoperability, and to deliver and test interoperable WLAN products and services. The WLIF was created in 1996 to allow vendors of WLAN products to work together to specify an interoperable standard, and provide test suites to prove interoperability. The five key areas that define WLAN interoperability, data communication, roaming, security, configuration, and coexistence are all defined in the OpenAir standard. Vendors who participate in the WLIF have designed their products to conform to a specification referred to as OpenAir. Please see [9] for more information about the WLIF. Clearly, interoperability is an important factor for any network, and WLANs are no exception. The IEEE 802.11 standard is an important step towards the development of interoperable products, but it is no panacea or silver bullet. The practical evolution of the standard to the point that compliance to the standard is a guarantor of interoperability may take a significant amount of time. In the meantime, the OpenAir standard offers a means to build a WLAN that supports products from a variety of vendors, with the clear advantage of proven interoperability. The WLIF is delivering interoperable, multivendor WLANs, and incorporates the IEEE 802.11 standard as well. 4.1.3
DECT and PHS
The DECT system standard, developed in ETSI, was completed in 1992 and enhanced for 3G applications up to 2 Mbps in the framework for IMT-2000 (IMT-2000 FT). DECT offers a communications solution over a relatively small coverage area if a large capacity is required. This radio access system allows frame relay data services up to 552 Kbps (and later up to 2 Mbps) and supports basic rate ISDN services. It is optimized for low-speed mobility between radio cells, thus avoiding the complexity associated with error correction, which is necessary in fast moving terminals. In Europe, a 20-MHz wide license exempt frequency band (1,8801,900 MHz) that accommodates 10 broadband TDMA carriers is allocated to the system; other regions in the world allocated frequency bands of similar size in the range of 1,900 to 1,920 MHz. PHS in Japan uses the same principles and operates typically in the frequency range from 1,900 to 1,920 MHz; however, it is not an IMT-2000 radio standard. The DECT standard covers a variety of applications, such as the following: • Cordless telephone for private use and business; • Wireless local loop (WLL);
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• WLANs; • Telepoint (public DECT) or PHS.
PHS is very similar; both standards are operating in nearly the same frequency bands (1,880 to 1,900 MHz up to 1,918 MHz) depending on the countries spectrum allocations. Both are using DCA based on the TDD scheme.
4.2 3G Standardization Two main standardization projects exist worldwide today; they are based on the 2G standards GSM and IS-95. UMTS standardization is built on GSM and therefore has its roots inside ETSI project groups. ETSI worked on the standardization of GSM already in an open partnership with ANSI/T1P1 in order to establish the PCS version of the GSM standard fully synchronized with GSM 900 and GSM 1800. One of the standardization targets of UMTS was to provide compatibility with GSM and to use the synergies in the core network part, where the evolution takes place. The overall objective was to consider required actions to enable UTRA- and GSM-based UMTS specifications to be prepared and promoted in a manner that makes them attractive to global partners such that they will be implemented worldwide. In December 1998 five standardization development organizations (SDOs) agreed to create the 3GPP [10]. The officially recognized SDOs of Europe, the United States, Japan, Korea, and China (who joined the 3GPP in May 1999) include ETSI, ARIB, TTA, Committee T1, and CWTS and have joined to work collaboratively for the production of 3G mobile system specifications by delegating the specification work for the third generation to 3GPP. They cooperate for the mission of 3GPP (i.e., as part of the IMT-2000 family of systems); that is, the provision of one set of common globally applicable technical specifications for UMTS based on evolved GSM core networks and the radio access technologies studied in ETSI as UTRA, and in ARIB as wideband code division multiple access (W CDMA), both FDD and TDD modes. A similar partnership project called 3GPP2 was founded subsequently to deal with cdma2000-related standardization issues. This project considers the evolution of IS-95 to 3G. 4.2.1
3GPP Develops Specifications for Global Use
The new approach to standardization in 3GPP is characterized by separation of the so-called individual members and partners spheres. The principle is to
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break collaborative global technical standards work away from the coordinated setting of regional or national standards. Both spheres appear as different categories of participation and different internal organizations in 3GPP. As shown in Figure 4.2, the internal work split of 3GPP is based on the distinction between the Project Coordination Group (PCG) and Technical Specification Groups (TSGs), besides support functions. The PCG is responsible for determining the overall frame and managing the progress of work. The TSGs prepare, approve, and maintain the 3GPP technical specifications and technical reports. Five TSGs exist, one each for the radio access network, core network, terminals, system aspects, and GERAN. Decisions are made by consensus in PCG, whereas in TSGs, unavoidable cases may be decided by vote as well as consensus. The partners sphere comprises two categories, organizational partners (SDOs) and market representation partners (MRPs). Both participate in the PCG of 3GPP. The former may be any SDO with the status to set standards nationally or regionally. The latter bring market requirements into 3GPP. The first MRP in December 1998 was the UMTS Forum, followed by the Global Mobile Suppliers Association (GSA), the GSM Association, the U.S. Wireless Communication Consortium (UWCC), and the IPv6 Forum. So-called individual members constitute the individual members sphere. Only entities registered as a member of an SDO can become individual members of 3GPP. All individual members have equal rights and act in their own right.
3GPP 3GPP Project Project coordination coordination group group Individual members Technical members contributions
Partner deliverables
Technical Technical specification specification groups groups
Regulators/ Regulators/ governments Mandates Partners Partners Market Market Organizational representation partners partners partners
Supportfunctions Support functions
Partners standardization Partnersstandardization process process
Figure 4.2 Overview of 3GPP development of global standards. (Source: ETSI.)
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Observers and guests may also be registered, especially if they have the qualifications to become a future partner. What distinguishes 3GPP is that the elaboration of technical specifications by individual members in the TSGs is completely separate from transposition, approval, and publication as standards, or parts of standards, by the SDOs, following the usual standardization process of the respective organizational partners. 3GPP was founded as an innovative way to develop technical specifications in worldwide collaboration, not to establish new legal processes of setting standards. Working procedures in 3GPP ensure that decision-making takes place at the lowest appropriate level. Maximum use is made of modern (electronic) working methods. The speci- fication work in 3GPP is progressing as planned. The first release of the UMTS specifications (Release 99) was ready at the end of 1999. 3GPP is continuing its work preparing UMTS releases by collecting requirements and initiating feasibility studies. Release 5 is the first step to the all-IP approach, the use of IP protocols throughout the UMTS network down to the mobile device. This step leads to a more integrated architecture that comprises network functions from the Internet (e.g., the ISP function and portal function). Figure 4.3 gives an overview on the UMTS and Internet-related standardization bodies and their standards and indicates the areas of commercial products. Figure 4.3 shows the scenario for multimedia services in the scope of an extended concept: IMT-2000/UMTS is merged with the Internet, the portal, and linked to content provisioning. The typical configuration, physically, is from terminal to computer or client to server. This is a many-to-one relationship, because there may be many physical terminals logically connected to one computer. Connectionless services exist on a user-at-host basis. As UMTS will combine the ITU-related standards with those related to the IETF, W3C, and the like, it will be faced with a number of new interworking issues. A new conversion function is, for example, the media gateway. These relate to quality, security, mobility management, and billing. A main issue is the interworking on the protocol layers where out-of-band and inband control functions have to be aligned. The standardization also has to specify impacts regarding addressing (ITU versus IP), which is impacting the Internet itself, and also UMTS. Thus, this topic will play a significant role in the future standardization within 3GPP. 4.2.2
Internet-Related Standardization
The IP is the method or protocol by which data is sent from one computer to another on the Internet. Each computer (known as a host) on the Internet
Standardization
End-to-end IP ITU framework standards SIM USIM
3GPP (ETSI, ANSI-TIA, ARIB, TTA, TTC, CWTS)
Terminal Terminal Windows-CE Windows -CE EPOC EPOC
Radio/ CoreNet Radio/ UTRA UTRA EDGE EDGE UWCC UWCC
Encoding AMR, MPEG4, MP3 Software standards
WAP MAP IS41 IS41 GPRS/IP GPRS/IP ATM ATM IN/CAMEL IN/CAMEL
253
Internet standards IETF W3C* P3P
Internet
Proprietary standards
Content
IP, SMTP, FTP, HTTP, CHAT, HTML, WML, XHTML /XML PSTN, Other PSTN Other ISDN PLMN PLMN ISDN
*W3C= World Wide Web Consortium P3P= Platform of Privacy Preferences Note: ISO, IEC, ITC standards are not shown
Figure 4.3 Global standardization scenario with Internet. (Source: UMTS Forum.)
has at least one address that uniquely identifies it from all other computers on the Internet. The most widely used version of IP today is IPv4, which is formally a set of specifications from the IETF [1]. IPv6 [11], the latest level of IP, is also beginning to be supported. The most obvious improvement in IPv6 over IPv4 is that IP addresses are lengthened from 32 to 128 bits. This extension anticipates considerable future growth of the Internet and provides relief for what was perceived as an impending shortage of network addresses. IPv6 therefore provides the possibility of addressing every device on Earth. Feature advantages of IPv6 include the following: • Addressing: IPv6 will restore the paradigm of end-to-end address-
ability. This was disrupted by network address translation (NAT), where the address of a packet from the internal network (mostly using private addresses, not routable in the Internet) has to be exchanged for an official IP address. Every packet has to be analyzed
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•
•
•
•
•
and its header changed. This breaks checksums, end-to-end security, and applications. Routing: IPv6 uses a routing hierarchy with aggregation. In the old days of the Internet the address spaces have been distributed all over the world without any real idea how the routing can be constructed based on this distribution. This changed with the introduction of classless interdomain routing (CIDR), and the registries created allocation policies supporting route aggregation and appropriately sized address ranges. The large and unstable routing tables will remain in IPv4. IPv6 will provide hierarchical address allocation limiting the number of entries in the routing tables to about 8,000, compared to some 90,000 with IPv4 at present. Plug and Play: IPv6 reduces the administration and management overhead by making Plug and Play really work. Autoconfiguration works together with the dynamical host configuration protocol and the domain name system so that the system administrator is not forced to configure every workstation and PC manually. The address is a combination of a routing part (prefix, 64 bits) and a host ID (EUI-64, 64 bits). The autoconfiguration mechanism reads the MAC address and composes a network-wide valid ID. The prefix is provided by a local facility and can be changed if necessary (change of provider) without difficulty and without manual reconfiguration of the hosts. Mobility: IPv6 supports mobility better than IPv4. IPv6 neighbor discovery and address autoconfiguration allow hosts to operate in any location without a special support (layer 2 addressing). The performance is improved because of traffic optimization. The flexible address structure is well suited for roaming. Extended security concepts might be adopted to meet the higher requirements from the mobile world. Header structure: IPv6 has an optimized header structure. Unlike IPv4, the header of IPv6 has fixed length of 320 bits with a possibility of additional extension headers, which are normally used only by the end nodes and fewer fields. This will make faster processing possible, and implementations in hardware will give the needed performance for fast networks. The option fields will be processed only if the option is present. Security: IPv6 will provide means for privacy and security as an integral part of the standard rather than as a separate protocol. With
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IPv4 the IPSec protocol is used, which is not different in principle to IPv6, but is very complex and difficult to use. Before IPSec can be used in a communication, it requires a check to see if the peer is supporting IPSec at all and what the implemented features are. Migration from IPv4 to IPv6
Although the standardization group in 3GPP has decided to base the IP multimedia development on IPv6, there is no common view on the timing for the introduction of IPv6 under the earlier releases. In the standards releases R99 and R4 of UMTS, a virtual connection between the terminal and the IP access point (ISP function) via GPRS is established when the user wants to use mobile Internet services. The temporary or permanent assignment of the connection is not explicitly fixed in the standards yet. Always-on, of course, leads practically to a quasi-permanent assignment, even in cases of a setup of a temporary connection. If users take the opportunity to set up virtual connections, changing in the ISP, the dynamic assignment has to be used. In case of IPv6, it has to be noted that many of the feature advantages depend on using a permanent addressthey would be lost with dynamically assigned addresses. One solution could be to allow multiple virtual connections. UMTS Release 99 offers options to use either IPv4 or Ipv6 for transport connections and specifies that either permanent or temporary allocation may be used. Mobile terminals, in practice, will need to support IPv4 for general compatibility and may choose to support IPv6 as well with a dual stack. UMTS Release 99 specifies that GPRS may use either IPv4 or IPv6, but the GTP specification specifies that IPv4 is mandatory and that IPv6 is an optional addition. UMTS Release 5 specifies the following: • Network elements of the IP connectivity services (between RNC,
SGSN, and GGSN) and IP transport for the CS domain may continue to use either IPv4 or IPv6.
• Terminals shall be able to access data services based on IPv4 and
IPv6.
• Network elements for the IP multimedia services shall be based
exclusively on IPv6.
This situation is summarized in Table 4.1.
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UMTS and Mobile Computing Table 4.1 Applicability of IPv4 and IPv6 in UMTS
Standard release
SGSNs, GGSNs
Mobile terminals and external Network elements for services IP multimedia
UMTS Release 99, IPv4, IPv6 optional Release 4
IPv4 or IPv6 In practice it will be IPv4, IPv6 optional
UMTS Release 5
IPv4 or IPv6 (IPv6 exclusively for IP multimedia services)
Not yet decided, possibly the same as R99, R4
IPv6 exclusively
Source: UMTS Forum
4.2.3
Standard Protocol Layers in UMTS
Figure 4.4 shows the end-to-end protocol layers and the underlying protocols for packet-switched UMTS services. On the switching and transport level there are the protocol layers that deal with network transport service and call setup, user authentication and security, transport and routing functions (including the tunneling to the IP access point), and the signaling and traffic handling for the physical information transport. The network service (NS) layer delivers encapsulated packets between the radio subsystem and the SGSN performing load sharing on this interface. The logical link control (LLC) is a sublayer of layer 2 according to the OSI structure. Its purpose is to convey information between layer 3 entities in the mobile device and in the SGSN. It provides one or more logical links with sequence control. The links are maintained when the mobile devices move from one cell to another. For error correction, it offers acknowledged mode. It also supports several QoS classes with different delay characteristics. On the interface to IP, it is converted into the Internet protocol UDP/TCP. The subnetwork dependent convergence protocol (SNDCP) is above LLC and performs the multiplexing and demultiplexing of data going across the LLC links. In addition, data compression takes place. SNDCP ensures the operation of the higher layer protocols, as they are the session and application service layer, which are common for end-to-end communications. This protocol is finally relayed to the GTP for interfacing the ISP function. The application layers include SMTP, HTTP, FTP, and the like, depending on the services offered in the network. In Release 5 of the UMTS standardization process, the SIP will be adopted for initiating, modifying, and terminating interactive user sessions
Node B
MS
SGSN
IGSN
IP host
RNC
Application
Application
SMTP, HTTP, CHAT, SIP, FTP, NNTP (MP3, MPEG 4)
Present. DNS
Session IP
Relay RLC BSSGP
RLC MAC
MAC MAC
N. service
GSM RF
GSMRF RF GSM
Physical
MS
IP
Relay SMTP GTP-U GTP -U
LLC
Um
BSS
UDP/TCP UDP/TCP
UDP/TCP
BSSGP
IP
IP
N. service
L2 L2
L2
Physical Physical Physical
L2/3 L2/3
Physical Physical
Physical Gn
IGSN
Gi
ISP
Portal Content/ASP
257
Figure 4.4 Protocols for packet-switched UMTS services.
SGSN
IP
GTP-U
LLC
Gb
PresentDNS Present. Session Session
Session IP service (Internetwork routing)
SMTP Switching and transport level
Internet
Standardization
Session, presentation, application level
IP CN
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for multimedia, including VoIP, audio, and video. SIP is an IETF standard and belongs to the application layer. It can invite participants to unicast or multicast sessions, which do not necessarily involve the initiator. It supports mapping and redirection for services from any location and allows the identification of users wherever they are. Participants are identified by SIP URLs. Requests can be sent via any transport protocol (UDP, TCP, or SCTP) because it uses several existing protocols: for message formatting, HTTP; for session negotiation, Session Description Protocol (SDP); for media transport, Real-Time Transport Protocol (RTP); for naming and mobility, Dynamic Host Configuration Protocol (DHCP), as well as domain name service (DNS).
4.3 Addressing and Registration Standards Addressing deals with services offered. A 3G device usually allows more than one service, thus, different addressing standards come into play. A device, whether it is stationary or mobile, needs at least one unique name or address in the environment in which it operates. This environment can either be public or private/corporate. Mobile notebooks, laptops, and handhelds, however, are used to log on to different networks at different places. Business people on business trips use mobile notebooks in hotels, companies, and airports to access e-mail and other data in the Internet. Thus, mobile access to the Internet is managed by the concept of mobile IP. Based on IPv4, mobile IP uses an address pool for allocating an IP-address to the temporary virtual connection, which will be established via GPRS. Mobility support in IPv6 uses two address layers. Each mobile PC or device is always identified by its home IP address, regardless of its current point of attachment to the Internet. While situated away from its home, a mobile node is also associated with a care-of address, which provides information about the mobile nodes current location. The care-of address is dynamically assigned to the mobile node by the hosting network. IPv6 packets addressed to a mobile nodes home address are transparently routed to its care-of address (also called tunneling). The protocol enables IPv6 nodes to cache the binding of a mobile nodes home address with its care-of address, and to then send any packets destined for the mobile node directly to it at this care-of address. For communications between devices and devices via networks with computers, at least two conditions have to be fulfilled: registration and addressing.
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Network Registration
In order to be accessible from a network, computers and UC devices need to be registered in the network and must have a network address at which they can be reached. Addressing of Fixed Devices
Fixed workstations or PCs of a network usually have a fixed network address that never changes. Fixed workstations and PCs that log onto a network for a limited time only rarely have a fixed network address of their own, but are usually dynamically assigned a currently unused address of the networks address pool. Addressing of Mobile Devices
The requirement of a system-independent equipment identifier for networked mobile terminals was agreed upon worldwide within industry and regulatory authorities. It is to provide one manufacturer-independent worldwide unique number per mobile terminal to support operator logistics. Roaming enabling is controlled via such a tag (illegal use can be prosecuted). For GSM and UMTS, the ITU numbering scheme is applied. It is agreed that the E.164 international mobile equipment identifier (IMEI) identifies the mobile terminal [12]. The identifier is used for tracking stolen terminals and for fraud prevention. IMEI in the past has also been used in relation to type approval. The mobile industry has developed assignment rules for the IMEIs. The Global Certification Forum (GCF) is discussing with manufacturers, operators, and regulators (including the ITU) the setup and administration of the necessary database. The discussed IMEI format of 15 digits is structured in the following way: • The first two digits identify the reporting body. • The subsequent four digits define the type allocation code. For
global roaming it is important that the code is handled globally.
• The next two digits identify the location of final assembly. • The remaining six or eight digits (extended) define the individual
number of the mobile device.
• The last two digits are complemented check digits.
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These digits are presented in BCD format. The industry considers IMEI an important market requirement. Therefore, the advantages of IMEI must be secured. There are the following targets: • A common scheme to be used for all mobile devices comprising all
IMT-2000 standards and device types; • Global support.
In more detail, the review has reached agreements on the following issues: • Mobile manufacturers and network operators aim to have a world-
wide recognized central body or organization to administrate and allocate IMEI codes for all 2G- and 3G-related mobile terminals. • The ITU should take over the database management and IMEI registration globally. • Where multimode devices are introduced and one band is 2G or 3G, the IMEI scheme must be used. Issuer Identifier Numbers (E.118)
To meet a cross-industry (banking, finance, travel, health care, telecommunications, entertainment, and others) requirement, the ISO with the International Electrotechnical Commission (IEC) have specified in ISO/IEC 7812 a numbering system for the identification of issuers of identification cards used in international and/or interindustry exchange. This means the exchange of card entities/institutions based on an agreement between the participants, and for example, includes credit card and charge card transactions. Part 1 of ISO/IEC 7812 refers to the numbering system to be applied. Part 2 provides the application and registration procedures. It should be noted that issuer identification numbers (IINs) beginning with 89 are for use in the telecommunication sector and are administered by the ITU-T, which has published Recommendation E.118 (The International Telecommunication Charge Card) to define the necessary rules and procedures in line with ISO/IEC principles. Addressing Mobile Devices with Full-Time AvailabilityAlways-On
Mobile devices that need to be accessible any time on a global scale (always-on) must have a fixed and globally unique address. Mobile networks handle the devices change of location and of provider networks and reroute
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packets or switch circuits accordingly. Those devices work in areas where either their home network is available, or a compatible, partnering network that admits them usually by a roaming agreement. It is the USIM card for GSM and UMTS inside a mobile phone to which the unique address belongs, and which gets a network internal address, the IMSI. Mobile devices in WLANs (e.g., in offices, warehouses, stores) are also accessible any time and thus require fixed addresses that are unique inside the WLAN. This requires advanced registration of the devices in the network before they can be used. The same applies to devices in the HomeRF environment. Addressing Mobile Devices with No Fixed Network Address
Those mobile devices do not need to be accessible at all times. They wander around and exchange information and data with different, previously unknown devices and networks at different places. Members of this group include Bluetooth and WPAN devices, mobile notebooks and laptops that log onto different networks, as well as Internet-enabled PDAs and handhelds. These devices have no fixed network address, but rather a unique identification number used for the manufacturing process and for identification in the after-sales market. When these devices are used to dial up to a network service provider, their ID number is used to grant access. They are then assigned a temporary network address to which the service station can send back the requested data. This address is valid as long as they are logged onit does not necessarily have to be an IP address, it just has to be valid and unique in their network. This happens automatically and dynamically with respect to the current network topology. Depending on the type of application, several possibilities and standards exist to enable this kind of networking. Addressing Bluetooth and IEEE 802.15 WPAN Devices in Ad Hoc Networking
It is characteristic of Bluetooth and WPANs (IEEE 802.15) that they have no fixed topology, and no (or few) static members. They are meant to allow new members quickly and to enable communication between them with no previous registration in the network. Bluetooth and WPAN devices only have a 48-bit ID number, which is used for the establishment of communication. In Bluetooth networks, the master (identified by certain characteristics like lowest or highest device ID) sets up the network and assigns each member a network address. The length of the address in Bluetooth networks is 3 bits, which is the reason for the limitation of Bluetooth piconets to a maximum of eight members.
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This kind of automatic and dynamic network establishment is also called ad hoc networking. An ad hoc network is a local or other small area network, especially one with wireless or temporary plug-in connections, in which some of the network devices are part of the network only for the duration of a communications session. In the case of mobile or portable devices, they are part of the network while they are in some close proximity to the other devices. In Latin, ad hoc literally means for this, further meaning for this purpose only, thus usually temporary. The term has been applied to future office or home networks in which new devices can be quickly added (e.g., by using Bluetooth). Ad hoc networking is expected to play an important role in future wireless networks. In contrast to conventional wireless networks (such as GSM and UMTS), ad hoc networks do not rely on preexisting communication infrastructure but allow direct communication between the nodes. When the radio propagation between two communicating nodes is not adequate, hop-by-hop routing between the nodes is employed. Due to the mobility of all nodes, the topology of such a network is continuously changing. This imposes a significant challenge in the design of algorithms, architectures, and protocols. Due to the lack of centralized entities, all algorithms must be performed in a distributed and self-organized fashion. Existing techniques for routing, addressing, mobility management, channel allocation, and so on, cannot be employed. The industry in general and the BSIG in particular are currently working on solutions. Jini is an approach to instant recognition of new devices or software objects in a network that would seem to make it easier to have an ad hoc network. Jini, however, does not help to register devices in a network, but rather helps their cooperation. Addressing IEEE 802.11 WLAN Devices
As mentioned earlier, the IEEE 802.11 standard for WLANs defines two different ways to configure a network: ad hoc and infrastructure (clientserver). In the ad hoc network, computers are brought together to form a network on the fly. There is no structure in the network, and there are no fixed points. Usually every node is able to communicate with every other node. Although it seems that order would be difficult to maintain in this type of network, algorithms, such as the spokesman election algorithm [13], have been designed to elect one machine as the base station (master) of the network with the others being slaves. Another algorithm in ad hoc network architectures uses a broadcast and flooding method to all other nodes to establish who is who. The standard specifies the etiquette that each station
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must observe so that they all have fair access to the wireless media. The standard provides methods for arbitrating requests to use the media to ensure that throughput is maximized for all of the users in the base service set. The infrastructure type of network uses fixed network access points with which mobile nodes can communicate. All devices have a fixed network address and need to be preregistered. IEEE 802.11 WLANs with infrastructure and central access point provide better throughput performance and are more popular.
4.4 Standards for Information Encoding The bandwidth limitations on air interface, real-time conditions, information redundancy, and the characteristics of radio transmission distortion all led to the development of encoding and compression standards. The first ones were developed for voice in 2G networks and later on they were improved and extended for 3G. Then, in the TV broadcast field, video and audio codecs were developed for high-quality compression. The introduction of data services in 2G mobile networks clearly showed the upcoming bottlenecks with information services, which are mainly Web-based. The real-time requirements differ from service to service: a voice dialog has high real-time requirements, a document download has very low ones. Video and audio streaming are delay-tolerant, howeverdepending on memory capacity on the mobile side, video clips or music could also be downloaded prior to play. Table 4.2 lists data transfer times in different networks. The typical transmission bit rates in the various infrastructures are shown in the top lines of the table. Voice is not shown here, although it is typically transmitted in wireline networks (PSTN, ISDN) with 64 Kbps and in GSM with 13 or 6.5 Kbps. The table makes clear that compression standards for audio and video are eminently important in order to offer these services at acceptable bit rates and tariffs, as well as to store such information in small devices with limited memory capacity. In the past, encoding standards were developed for specific services and applications (e.g., for voice, sound, and video). Now, mobile multimedia requires encoding techniques that can be used for different applications (e.g., for real-time video as well as for video streaming or for video e-mails). In addition, roaming users need a common standard for the many services they intend to use. Such requirements led to considerable improvements of the encoding standards. They now provide flexibility for various applications and tools to help accommodate the core standard for the specific use.
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UMTS and Mobile Computing Table 4.2 Service Transmission Times in Mobile and Fixed Networks Transfer Time
Service Data Volume
2G GSMGPRS
Fixed PSTN/ISDN
3G UMTS
9.6 Kbps 50 Kbps
≤ 64 Kbps
128 Kbps 384 Kbps
2 Mbps
E-mail 5 KB
8 sec
1.7 sec
1.6 sec
1.2 sec
0.5 sec
0.5 sec
SMS with photo 5 KB (JPEG 2000)
8 sec
1.7 sec
1.6 sec
1.2 sec
0.5 sec
0.5 sec
Web page 20 KB
20 sec
4.5 sec
4 sec
2.4 sec
0.8 sec
0.5 sec
Document 100 KB
2 min
35 sec
25 sec
12 sec
4 sec
1 sec
3-min audio CD 2 MB (MP3)
40 min
9 min
6.5 min
3 min
a
a
10s videoclip 600 KB (MPEG-4)
10 min
2.5 min
1.5 min
45 sec
15 sec b
= User acceptance 15 sec. Optimal CD-quality streaming = 128 Kbps. b Video streaming. a
The formats of video and audio are vital to mobile computing. The selection of the solution determines quality, quantity and storage, complexity encoding and decoding, bit-rate requirement, methods to access media, and usability. The upcoming streaming media sectordriven by companies that enable the live broadcasting or individual point-to-point streaming of audio and video via the Internetwill have a real impact on corporate culture and private lives. Corporate communications, knowledge management, education, and many other application fields will appreciate streaming services, even while on the move. A significant indication of the market potential was revealed in 2000 when Yahoo launched its Webcast Studio. With its new compression techniques, a number of technological bottlenecks and bandwidth problems were solved. There is a wide range of proprietary compression techniques available in the streaming market. This is slowing the uptake of streaming media because of interoperability problems. To counter this, the ITU and ISO
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standardization organizations, as well as industry alliances like the Internet Streaming Media Alliance (ISMA), are developing and promoting open standards. 4.4.1
Voice Encoding
The advanced multirate (AMR) codec was specified to overcome the problems of GSM radio performance. AMR specifications were released, and the products came into the market by 2001. This encoding standard may continue as it is known that UMTS terminal performance will not improve significantly. This is true when considering the additional coding schemes required for wideband (7 kHz) speech and higher bandwidth audio services. The AMR codec has the potential to deliver a consistent wireline quality for speech. The AMR codec is now developed for 3G multimedia video telephony as well. It has eight modes: 12.2, 10.2, 7.95, 7.47, 6.7, 5.15, and 4.75 Kbps. The 12.2-Kbps mode is the GSM enhanced full rate; the 7.47Kbps mode is the U.S. TDMA IS-136 enhanced full rate; and the 6.7-Kbps mode is for the Japanese PDC enhanced full-rate codecs. 4.4.2
Bitmap, Graphic, and Photographic-Image Encoding
Both the ISO and the ITU have developed encoding standards for images, video, and audio. The IEC joined the ISO for these developments. The enhanced messaging services in GSM and the i-mode service in PDC show the value of agreed standards for transmission of simple bitmaps, graphics, and sounds. The graphics interchange format (GIF), used in the Internet, does not seem to be appropriate for mobile use. Thus, the WAP Forum developed the wireless bitmap (WBMP), a graphic format optimized for mobile devices; i-mode uses a similar standard. JPEG and JPEG 2000
The Joint Photography Experts Group (JPEG), the ISO, and the IEC, coordinated via the Joint Technical Committee (JTC1) developed a new compression standard called JPEG 2000. This is a compression standard for color images. It reduces the file sizes down to 5% of their original size; some details, however, are lost after decoding. It has progressed from the moving picture encoding standards MPEG-1, MPEG-2, and MPEG-4. This new encoding standard is a further development of JPEG and is better suited for transmission over Internet and wireless networks. It provides improvements for the following:
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• Picture quality; • Limited resources (transmission) in real-time environment; • Compatibility with MPEG-4 and with fax; • Support of metadata to describe picture contents.
The baseline JPEG scheme is for compressing a single image using lossy compression techniques. The image will not be the same as the original after encoding and decoding. The JPEG standard exists as the ISO-10918-1 or ITU-T T.81 specifications. The encoding standard allows picture compression between 4:1 and 100:1 for monochrome and color images. Thus, the data volume of a 2-million pixel photograph, which is from 80 to 300 KB, could be reduced down to 3 KB. 4.4.3
Video and Audio Compression
Movement of data that adheres to accepted standards and efficient packaging will form one of the building blocks of video and audio communication. Equally, UMTS will also contribute greatly to the evolution of these standards and packages. Therefore, close attention to the current state of affairs and the developments in the coding of audio, video, and static images will be a necessary planning element. The movement of images, video, and audio among digital devices requires standardized approaches to coding the data to make it usable under a variety of environments. Additional consideration is also given to minimizing the size of the information while paradoxically attempting to enhance the users experience and value derivation. In this section we will review only some of the more popular coding techniques and standards for various media. MPEG Video Compression
The Moving Picture Experts Group (MPEG) standard comprises three main specifications: system, video, and audio. Additionally, there are also other supporting specifications and recommendations, which share the same ISO specification number. The MPEG-2 video standard (ISO-13818-2) is backward compatible with the MPEG-1 video standard (ISO-11172-2). In general, the MPEG-2 video standard is more complex and powerful. MPEG-1 is mainly for lower bit rate applications (e.g., computer games,
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video conferencing, CIF movie content), while MPEG-2 is targeted for digital TV (e.g., satellite or cable TV). One main feature of MPEG is that it has intraframe compression like JPEG (compression of redundant information within the same image) and interframe compression (compression of redundant information among several temporally related frames). It also has motion-based compensation, which is similar to using data interpolation if the objects start and end points are known. The MPEG specification has requirements and recommendations for the MPEG encoder and decoder. The fundamental concept in MPEG is that complexity lies in the encoder and not the decoder. The ideal situation for downlink streaming to the mobile device is that computation and memory resources are minimal in the decoder. MPEG-1 AV Compression (ISO/IEC 11 172)
This is the first video encoding standard initially developed for video-CDs with transmission rates of 1.5 Mbps. Its layer 3 was used as a pure audio format for the compression of hi-fi music and offered transmission rates from 128 Kbps upwardsknown as the MP3 standard. Audio Compression with MP3 (MPEG-1 Layer 3 or MPEG-2 Layer 3 Audio)
The standard is described in the ISO-11172-3 MPEG-1 specifications. MP3 is a compression standard set up by the MPEG-1: a specific compression technique as a modified layer 3 of the MPEG-1 and 2 standard (pure audio format). It compresses audio files to one-twelfth of a standard audio file. MP3 is the audio standard for CD quality with medium bit rates. Ten minutes of CD-quality music requires less than 10 MB. In contrast, regular fractal techniques require 100 MB. MP3 audio streaming in CD quality is optimally possible with 128-Kbps transmission bit rates. A new audio compression format is advanced audio coding (AAC). It is also defined in the MPEG-2 moving-picture standard, which is more efficient than MP3. Another compression technique called MP4 (no relation to MPEG-4 video compression) has been proposed to the Recording Industry Association of America. This variant allows copyright information and links to official music sites to be embedded in the music files. Meanwhile, further audio encoding standards are also available: Microsoft Windows Media Audio (WMA), Real Audio 8 from Real Networks, ePAC from Lucent for lower bit rates, AAC from Psytel, and MP+. A brief explanation of the most important ones follows:
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• WMA is used for downloading, streaming, and playing audio files. • Real Audio 8 is a compression technique supporting FM stereo
quality sound. The software is usually included in desktop and laptop software. • MPEG AAC is the MPEG-2 audio for CD-quality sound. An extension of MPEG AAC is part of MPEG-4. Regarding security, the secure digital music initiative (SDMI), a crossindustry organization of consumers and computer companies, has been working together with the recording industry on a specification for digital music security. SDMI is working on a standard that describes the HW requirements for compliant music players (1999). For this, SDMI has selected a robust water marking technology. MP3 Pro
This is an improved MP3 encoding standard that allows streaming with 64 Kbps, which saves 50% memory capacity in comparison to MP3. It is mainly developed for Internet broadcasting. It is backward compatible to MP3. The standard allows audio quality up to 15-kHz bandwidth (music, voice). MPEG-2 AV Compression (ISO/IEC 13818)
MPEG-2 is the compression technique for digital video disc (DVD). Twohour MPEG-2 video movies require 1.2 GB data volume. MPEG-2 has become a pervasive standard for digital TV, digital cable, broadcast satellite TV, and the DVD. The success of MPEG-2 in TV signals the importance of an open new standard for wireless point-to-point distribution systems, with even better compression and for lower bit rates. There are several categories in the MPEG-2 video standard. These categories govern the capability and set limits on the MPEG stream. The most popular category (DVD, cable TV) is called main profile at main level: maximum video resolution is 720 × 480 (NTSC) or 720 × 576 (PAL), maximum bit rate is 15 Mbps, and decoding buffer requirement is 1.75 Mb. There are other categories, profiles, or levels to support other video resolution (e.g., MPEG-1 type video, HDTV, medical imaging). MPEG Decoder Memory Usage
The MPEG bit buffer is a FIFO in the decoder that is specified to store the raw MPEG data prior to decoding. The MPEG specification requires the
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encoder to generate data in such a way that the MPEG bit buffer does not overflow or underflow. For the main profile, the MPEG bit buffer is specified to be 1.75 Mb. In addition to the bit buffer, the MPEG decoder must allocate frame buffer(s) for decoding and presentation. The number of buffers and the size of each is dependent on decoder hardware, video resolution, pixel bit resolution, and software implementation. To save memory capacity and transmission time, new encoding schemes were developed. They can condense this size down to 600 MB with good quality (near-VHS). For example, the DiVX from Microsoft, 3ivx and Windows Media Encoder (WME) Version 7.1 support audio and video with 30 profiles, which can provide near DVD quality with 500-Kbps streaming. DiVX is based on MPEG-4. The digital TV broadcast in Europe, called DVB, also uses this encoding standard. MPEG-3 was developed for highdensity TV and was replaced by MPEG-2. MPEG-4 Near-DVD Quality
The MPEG-4 standard (ISO/IEC-14496) [14] is for transmitting low bit rate streams (less than 64 Kbps) and is therefore most appropriate for mobile applications. More than just a teleconferencing standard, MPEG-4 takes into account user interactiveness, object-oriented usability, context-sensitivity, flexibility, and extensibility. It has hooks that deal with some of the issues related to the convergence of interactive TV data, computer audio-video data, and telecommunications AV data. This is an emerging standard that allows near DVD streaming quality with 400600-Kbps bit ratesacceptable bit rates for UMTS applications, although lower bit rates with less quality can be achieved. The 3GPP standardization bodies have chosen this standard for 3G mobile terminals. The objective of MPEG-4 is a flexible, extendable encoding. This is expected to help with the level of interactivity of multimedia objects of a scene as well as to mix synthetic and natural audio information seamlessly. One of the main attributes is its capacity for lower bit rate transmission with good quality. The standard is similar to the ITU H.263 video conference standard. Fractal coding is a relatively new approach to image coding in a low bit rate scenario: The concept is to represent an image sequence by a transformation using self-similarity. A fractal image can be generated from an arbitrary start image by applying a set of mappings on the image interactively until the image is stable.
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Some important MPEG-4 characteristics are as follows: • Bit rates: typically between 5 Kbps and 10 Mbps; • Formats: progressive as well as interlaced video; • Resolutions: to beyond TV.
The common intermediate format (CIF) and the quarter CIF (QCIF) are digital video formats that have video resolutions of 352 × 240 pixels and 176 × 120 pixels, respectively. New digital television standards are well underway in Asia, Europe, and the Americas. Three key elements, which are present in all of the highdefinition initiatives, are widened TV aspect ratios (16:9), increased picture resolution, and compact disc audio qualityalthough each market is choosing its own direction in terms of audio and video coding. In Europe, the high-definition multiplexed analog components (HD-MAC) via direct broadcast satellite (DBS) system was adopted, but was replaced by the satellite operator consortium that formed a fully digital technology called DVB. MPEG-4s future developments will pay close attention to contentbased interactivity, compression, and universal access. The following other functionalities that may be provided by other developments will also need to be addressed: • Synchronization; • Auxiliary data capability; • Virtual channel allocation flexibility; • Low delay mode; • User controls; • Transmission media interworking; • Interworking (interoperability) with other multimedia systems.
MPEG-4 benefits include the following: • It is the first standard that combines one-way and two-way video
into a single standard.
• It allows for easy manipulation.
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• It allows content providers to encode once and deliver everywhere.
A single stream can handle cable, satellite, and wireless, and can be delivered over multiple bit rates. This cost-effective solution is possible due to two features in MPEG-4 that MPEG-2 does not have: a more flexible range of bit rates (from 9.6 Kbps to 6 Mbps), and an error resiliency that helps ensure quality even over high bit error rate links.
New versions of MPEG-4 are presently underway (e.g., MPEG-4 V3, a Belgian development). MP4 V3 (DivX)the Video MP3
This standard is an improvement of MPEG-4. Microsofts MP4 V3 version 1.0 conforms with the I3DivX codec. The quality is comparable to VHS copies with 150 Kbps and to DVD with 450 Kbpsthe compression factor is approximately 10. For example, a 7-GB DVD video could be compressed to 700 MB. Fully compatible MPEG-4 codecs are OpenDivX and 3ivX. MPEG-5 and MPEG-6
These standards were initially planned by ISO, but they were skipped in favor of MPEG-7. MPEG-7
This encoding standard is a further development towards composition of video displays from different sources. A mosaic of the most important key images is transmitted to the users device. The received information is then used to modify the already existing information on the display. This standard allows more adaptability for different devices and provides the flexibility to combine video information from different sources (multimedia composition with multimedia description scheme using XML markup language extensions). MPEG-21
This future planned standard should cover all open areas in the field of composition and compression techniques. Ubiquitous devices and networks enable access to information and services from almost everywhere at any time. To allow interaction between different communities, each with their own models, rules, procedures, interests, and content formats, a common encoding framework standard is needed. The MPEG-21 vision is to define a
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multimedia framework to enable transparent and augmented use of multimedia resources across a wide range of networks and devices used by the different communities. MPEG-21 will elaborate key elements by defining the syntax and semantics of their characteristics, such as interfaces. MPEG-21 will also address the necessary framework functionality, such as the protocols associated with the interfaces and mechanisms to provide a repository, composition, and conformance. Users accessing content should be offered services with a (a priori) known subjective quality (at a known and agreed-upon price). They should be shielded from network and terminal installation, management, and implementation issues. This ease of use becomes increasingly important given the imminent installation base of multiple, heterogeneous coexisting (wired and wireless) networks, such as GPRS, UMTS, DVB-T, -S, -C, xDSL, LMDS, MMDS, WLANs, and Bluetooth, among others. This implies that the high-level user parameters (mainly quality and price) need to be mapped in a transparent way to the underlying network and terminal parameters. The user should thus be given a service with a (guaranteed) QoS, without having to worry how this translates into network and terminal QoS. From the network point of view, it is therefore desirable that the application servicing the user can translate the user requirements into a network QoS contract. This contract, containing a summary of negotiated network parameters, is between the user (or an agent acting on behalf of the user) and the network. The implementation of this QoS contract is of dynamic nature given the changing environments in which the user will be communicating (e.g., a bit-rate reduction in wireless access when moving). This negotiation process could be handled automatically by software agents. Seven architectural elements are identified as key to the multimedia framework: 1. Digital item declaration: a uniform and flexible abstraction and interoperable schema for declaring digital Items; 2. Digital item identification and description: a framework for identification and description of any entity regardless of its nature, type, or granularity; 3. Content handling and usage: interfaces and protocols that enable creation, manipulation, search, access, storage, delivery, and (re)use of content across the content distribution and consumption value chain;
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4. Intellectual property management and protection: the means to enable content to be persistently and reliably managed and protected across a wide range of networks and devices; 5. Terminals and networks: the ability to provide interoperable and transparent access to content across networks and terminals; 6. Content representation: how the media resources are represented; 7. Event reporting: the metrics and interfaces that enable users to understand precisely the performance of all reportable events within the framework. According to the ISO groups, the first release of the MPEG-21 framework standard will be in 2002. Videoconferencing
Videoconferencing and video phone technology has undergone active development for the past two decades. Due to its early start, there are quite a few teleconferencing standards and recommendations: • T.120: real-time data conferencing; • H.261: video codec for audiovisual services at n × 64 Kbps; • H.263: video coding for low bit rate communication ≤ 64 Kbps;
H.263 V2 is the latest version and copes with extended types of source formats and scalability;
• H.320: ISDN videoconferencing; • H.323: video conferencing on LANs; • H.324: low bit-rate video and audio communication.
Interestingly, the MPEG-1 standard is based on H.261 and JPEG technology. The n × 64 digital teleconferencing standard operates in the range of 64 Kbps to 2 Mbps (e.g., H.261 and H.320). The term n × 64 signifies that the bit rate is a multiple of 64 kbps. Recommended Media Encoding Standards for 3G Applications
The characteristics of the media encoding standards (see Table 4.3) indicate considerable improvements over time. It appears that JPEG 2000, MP3, MP3PRO, and MPEG-4 will be most appropriate for 3G applications [15]. If a reduced screen size and resolution of a mobile device are envisaged, such
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Encoding Standard
Recommended Streaming Bit Compression Rate
Media
Quality
JPEG/ITU-TT81 JPEG 2000
Still picture
Medium to high 1:4 resolution 1:100
64 Kbps
MPEG-1
Moving picture
Video CD
1:4
384 Kbps to 1.5 Mbps
MPEG-2
Digital TV
DVD
1:68
215 Mbps
MPEG-4
Digital video
DVD
1:10
64500 Kbps
MP4V3 (DivX)
Digital video
VHS
1:20
≤ 150 Kbps
MP3 MP3PRO
Digital audio
CD
1:10 1:20
128 Kbps 64 Kbps
Real-time transmission
Variable
n × 64 Kbps
H.261, H.263, H.320, VideoconferH.323, H.324 encing
encoding standards would make operation in the range of 64 to 384 Kbps quite feasible. However, their ability for mobile applications in 3G still has to be proved. Their integration into terminal software is another important issue. A few examples: Quicktime is a video and animation system developed by Apple Computer. It supports JPEG and MPEG standards. Active Movie is a streaming compression technology developed by Microsoft that is part of the Internet Explorer. It supports many multimedia formats including MPEG. RealVideo is a streaming compression technology for video over the Internet. It is also usable for Internet multicast. Windows Media Video is a compression technology for the download and play of video files. It uses the MPEG-4 standard.
4.5 Software, Protocols, Computer Languages, and Smart Cards Once devices are registered in a network and hold an address, standardized protocols and software systems enable their cooperation. Today, the general and universal set of protocols beyond the physical transport layer consist of the IP protocols and their higher layer protocols: TCP for end-to-end data
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transfer, then applications-oriented protocols like SMTP for e-mail, FTP for file transfer, HTTP for the Web, and many others. Besides SMTP, the most popular protocol technique is HTTP and network socket programming. This direct way of establishing a peer-to-peer communication inside a network is a very plain and straightforward approach. It is very error-prone and has low foresight because it is difficult to extend. Communication between different hosts or devices has to be set up explicitly with the hosts network addresses. Some technologies, however, exist that build up on HTTP but supplement and conceptualize it with XML, like Microsofts SOAP. Middleware Standards
Another kind of technology in which standards are involved is Middleware (see Figure 3.40). It mediates between devices and applications and enables cooperation. Middleware is a software or software system that connects separate applications, software entities, or devices and passes data between them. It can be described by technologies like CORBA, Java RMI or Jini, HAVi, Plug and Play, and (ever increasingly) more. They provide methods and protocols for exchanges of data and method invocations, as well as some methods for service and object discovery. The roots of CORBA are distributed applications in computer networks and is intended as a distributed computing technology. It also allows dynamic binding and dynamic invocation of objects and services at run-time. It is therefore an important middleware technology for future networks with fixed topologies. As CORBA requires explicit registration of services without providing a discovery-service or agent to look up new available services or hosts, it is not well suited for ad hoc and dynamically changing networks, as used in many UC scenarios. The same problem applies to Java RMI, the Java middleware that mediates between distributed Java objects in networks. Both RMI and CORBA only work with predefined networks, as they need IP addresses or host names to reach other hosts and devices in the network. Jini, Suns spontaneous networking technology, is based on RMI and overcomes this restriction. Jinis lookup service queries the available network area (also known as Djinn) to discover what hosts and what services are available. Jini is more the kind of technology that was created for UC, as it allows the operation of a dynamically changing distributed system. It includes dynamic service discovery, joining, lookup, leasing, and more. Jini is platform-independent but needs a Java-capable OS. In answer to Jini and the resulting new possibilities, other companies and groups have responded with different approaches. An organization called
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HAVi, formed by leading consumer electronics manufacturers, responded with a standard for digital AV and multimedia applications at home. Microsoft has responded to the development of Jini with its own specification for easy networking: Universal Plug and Play (UPnP). This is an extension of the plug and play capabilities introduced with Windows 95 and now Windows CE to discover new devices. Sun, however, responded to UPnP with its OSGI, and has the support of many industry partners. Another interconnection home network standard is CEBus Home Plug and Play that makes use of the Powerline. WAP is also a middleware technology intended for mobile phones to internetwork and to access the Internet. 4.5.1
SOAP
SOAP enables program communication by using the Webs HTTP and XML as the mechanisms for information exchange [16]. SOAP specifies exactly how to encode an HTTP header and an XML file so that a program in one computer can call a program in another computer and pass information. It also specifies how the called program can send a response. SOAP was developed by Microsoft, DevelopMentor, and Userland Software and has been proposed as a standard interface to the IETF. It is somewhat similar to the Internet Inter-ORB Protocol (IIOP), a protocol that is part of CORBA. Sun Microsystems RMI is a similar client-server interprogram protocol between programs written in Java. An advantage of SOAP is that program calls are much more likely to get through firewall servers that screen out requests other than those for known applications (through the designated port mechanism). Since HTTP requests are usually allowed through firewalls, programs using SOAP to communicate can be sure that they can communicate with programs anywhere. 4.5.2
CORBA
Distributed processing will be one of the cornerstones in future telecommunications systems. In particular, the interoperability architecture introduced in CORBA 2.0 seams suitable for telecommunications, which is by its very nature a multidomain field. CORBA is specified by the Object Management Group (OMG) [17], which defined an architecture called objectmanagement architecture (OMA) that provides the conceptual infrastructure upon which all OMG specifications are based. The OMA is now the most important de facto standard in the area of distributed computing.
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The key building blocks of the OMA are shown in Figure 4.5. They include the object request broker (ORB), object services, common facilities, domain interfaces, and application interfaces. The object request broker, commercially known as CORBA, is the communications backbone of OMA. The ORB transparently allows its clients to make requests and to receive responses using object invocations in a distributed environment. Object services is a collection of services (interfaces and objects) that support basic functions for using and implementing objects. Common facilities is a collection of services that many applications may share but which are not as fundamental as the object services. The common facilities are divided into two major categories: horizontal common facilities (which are used by most systems) and vertical market facilities (which are domain-specific). Domain interfaces represent vertical areas that provide functionality of direct interest to end users, in particular application domains. Domain interfaces may combine some common facilities and object services but are designed to perform particular tasks for users within a certain vertical market or industry. Application interfaces, while not an actual OMG standardization activity, are critical when considering a comprehensive system architecture. The application interfaces represent component-based applications that perform particular tasks for a user. Common Facilities facilities Common User UserInterface interface Application Applicationobjects Objects
Domain Services Domain services
Task Management management Task
CORBAmed CORBAmed
InfoManagement management Info
CORBAfinance CORBAfinance
SystemManagement management System
usw. etc.
Object request broker
Persistence LiveLifeCycle cycle Naming Persistence Externalisation Externalization
Events Events
Con Concurrency Collections Collections Properties Properties currency
Transactions Transactions
Query Query Relationships Relationships
OBJECT Object SERVICES services
Figure 4.5 CORBA.
Security Security
Time Time
Trader Trader
Change Change Licensing Licensing management Management
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In distributed systems, software components operate in different environments. They have to collaborate through appropriate interfaces and methods in an overall system. CORBA [18] is the standard that allows this. It uses the remote procedure call (RPC) technique and adds object orientation, transparency (of address and place), and independence from the underlying system. It allows the creation, distribution, and management of distributed program objects in networks. CORBA is a specification produced by the OMG [17] that addresses interoperability in distributed heterogeneous environments. The CORBA standard represents industry consensus from more than 800 companies. It defines an ORB for transparent invocation on remote objects, as well as supporting system level object services and higher level common facilities. CORBA assumes a heterogeneous environment in which objects implemented in different languages on different platforms by different vendors can interoperate. There are many implementations of the CORBA standard, some of them in the form of commercial products that have demonstrated strong market acceptance. The essential concept in CORBA is the ORB. ORB support in a network of clients and servers on different computers means that a client program (which may itself be an object) can request services from a server program or object without having to understand where the server is in a distributed network or what the interface to the server program looks like. To make requests or return replies between the ORBs, programs use the General Inter-ORB Protocol (GIOP) and, for the Internet, IIOP, which maps GIOP requests and replies to the Internets TCP layer in each computer. CORBA also provides some mechanisms if the network structure changes. Dynamic binding of objects and services is accomplished by the so-called dynamic skeleton interface, which is a run-time binding mechanism for creating server interfaces on the fly. Dynamic invocation of services (methods) is possible through the dynamic invocation interface, which allows the discovery and use of registered server interfaces at run-time. Locator services, such as the naming service (to request an object by name) or trader service (returns references to objects that match some criteria), can be queried for new services, but they only report on services they know about. Thus, CORBA can be used in networks with changing structure; however, explicit registration at dedicated servers and access points is necessary. CORBA might not be well suited for UC scenarios, in which new devices, once attached to the network, should immediately be able to collaborate without any user intervention. CORBA would require the user to provide the device with the network servers IP address or name. At this
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point, there is no CORBA implementation that involves some kind of discovery agent. This is because CORBA was not intended for that use, and, if it had a discovery agent or service, it would compete with Jini, an advanced middleware technology that was developed specifically for dynamically changing network topologies and service discovery in unknown networks. 4.5.3
Java Programming and Java Remote Method Invocation
Java is a trademark of Sun Microsystems; thus, it is a proprietary standard for programming. ETSI has adopted Java for the USIM/UICC standardization. The UICC will therefore include the JavaCard open platform for SIM/ USIM cardrelated applications. Java RMI is supplied as part of Sun Microsystems Java development kit (JDK) and is the Java distributed computing technology for TCP/IP networks. Java RMI is the Java version of RPC and is a middleware technology similar to CORBA. Unless it mediates between Java objects only, it is less transparent, more complex to use, and does not come with the same huge set of predefined services. RMI is implemented as three layers between the application program and the JVM (which in turn sits on top of the OS). The three layers are as follows: 1. A stub program in the client side of the client-server relationship, and a corresponding skeleton at the server end. The stub appears to the calling program as a program being called for a service. (Sun uses the term proxy as a synonym for stub.) 2. A remote reference layer that can behave differently depending on the parameters passed by the calling program. For example, this layer can determine whether the request is to call a single remote service or multiple remote programs as in a multicast. 3. A transport connection layer, which sets up and manages the request. A single request travels down through the layers on one computer and up through the layers at the other end. Like CORBA, Java RMI enables asking other network hosts or devices about available services, if the partners network address is known. Just like CORBA, RMI does not provide any discovery service. Because of this, Sun came up with Jini, which allows quick service discovery in dynamically changing distributed services and applications networks.
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4.5.4
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Jini
The Jini approach aims to create an environment where network attachment of a wide range of devicesincluding (but not limited to) cellular terminalsis easy and reliable. Jini defines a small, simple set of conventions that allows services and clients to form a flexible distributed system that can change over time. As described in Section 3.3.4.5, Jini sits on the Java RMI system, which is part of the Java platform. With a development and deployment model similar to that of the Internet, the success of Jini technology requires that the underlying protocols and infrastructure become pervasive through a strong community of participants and partners. The Sun Community Source License (SCSL) is a mechanism to build such a community around Jini technology. The SCSL opens the source code for Jini software to the community of Jini technology licensees, who are free to use it, extend it, improve it, and repair it. Community members may maintain proprietary implementations, though interfaces must be published for other community members. Jini technology is already emerging as major manufacturers deploy initiatives to enable their devices with Jini technology [19]. 4.5.5
HAVi
Home network technology standards are becoming essential to the consumer electronics industry as digital content and the Internet become more pervasive. Various competing home network solutions can be structured into two groups for standardization: those dealing with physical interconnects and those dealing with the services and applications. The former include X-10, CEbus, HomePNA, HomeRF, Ethernet, and IEEE 1394. HAVi belongs to the second group [20]. It was established in November 1999 by eight leading consumer electronics manufacturers (Sony, Matsushita, Philips, Thompson, Hitachi, Toshiba, Sharp, and Grundig), in order to promote its common digital AV home-networking architecture. Their HAVi core specification focuses a home network standard for AV applications and home entertainment. Home entertainment networks based on the HAVi specification promise to play an important role in enabling entertainment providers, electronics manufacturers, and consumers to take full advantage of a wide range of new interactive services made possible by the advent of digital technology. Digital content received from digital broadcast, network, and package media can be distributed throughout the home to any appliances on the network. Interoperable digital AV appliances with appropriate digital content protection will provide an infrastructure for many new services, such as
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high-speed Internet access, video on demand, and home AV server applications. The HAVi architecture adopted the IEEE 1394 standard (FireWire) and IEC 61883 protocol standard for asynchronous transactions. The types of devices supported by HAVi include tuners, VCRs, clocks, cameras, AV discs, displays, amplifiers, modems, Web proxies, and converters. Their architecture builds strongly on Java (it is specified as an open Java platform) and combines this with elements and design structures of CORBA. It defines software elements, application programming interfaces (APIs), and communication protocols that allow devices to interconnect and interoperate. It also offers plug-and-play connectivity, an intuitive user interface, and a so-called future-proof expandability [20]. Small information appliances supporting the HAVi architecture standard can interoperate with at least the AV entertainment systems produced by the HAVi manufacturers. HAVi is some form of competitor to Suns Jini (it is not a direct competitor as it targets different devices). Collaboration is needed to create a bridge that links HAVi devices in the home to services provided by Jini over a network. This would allow both digital AV appliances to access remote network services (such as a storage service for large video files) and users to remotely operate digital AV appliances and PCs in their homes from remote or mobile locations (e.g., access the home entertainment system to tape a television program while away from home). HAVi Specification Version 1.0
The HAVi specification has been designed to address all aspects of home networking in an IEEE 1394based, digital AV environment. The core specification included components for interchanging messages and events on IEEE 1394, registering and discovering device capabilities across the network, and for managing digital AV streams and devices. Version 1.0 offers a more efficient, reliable, and secure solution featuring the following improvements: • Java has been adopted as the HAVi byte code to make it possible
to represent devices and functions through the use of platformindependent, object-oriented APIs. This will allow software developers to create interactive Java-based applications and user interfaces. HAVi-compliant applications can be installed in electronics appliances by the manufacturer or downloaded from the Internet and other sources.
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• Version 1.0 incorporates new features, including security that pro-
tects against rogue applications and viruses, an event scheduling element that supports functions like programmed recording, and standard programming interfaces that are used to control device functions. • The new resource manager component performs a wider variety of operations. It handles device usage conflicts, coordinates programming of scheduled events (such as timed recording on a digital recorder), and monitors the network for removal of reserved devices. 4.5.6
UPnP
Microsoft has responded to the development of Jini with its own specification for easy networking: UPnP [21]. It is an extension of the plug-andplay capabilities introduced with Windows 95. UPnP is a device-discovery protocol that competes with Jini. Microsofts Universal Plug and Play Forum, which includes Sony, Intel, and General Electric, imagines interacting smart appliances at home: microwaves that read UPC codes, display recipes or ingredient information, and start cooking; refrigerators that are connected to the Web, to allow consumers to monitor home appliances through the Internet. A consumer, for example, could go to work, display a Web page, and turn off a stove burner that had been left on. UPnP is an open standard technology for transparently connecting appliances, PCs, and services by extending Plug and Play to support networks and devices, peer-to-peer discovery, and configuration. UPnP specifies the following: • Automatic IP address allocation; • Delta encoding in HTTP; • Simple Service Discovery Protocol (IP-based); • Multicast and unicast UDP HTTP messages; • General event-notification architecture base: client to arbiter; • Flexible XML processing profile (FXPP). 4.5.7
OSGI
A direct competitor to Microsofts UPnP is OSGI [22]. It is an industry plan formed by Sun Microsystems, Alcatel, Ericsson, IBM, Lucent Technologies,
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Motorola, Nortel Networks, Oracle, Philips and others, for a standard way to connect devices, such as home appliances and security systems, to the Internet. With such a standard, home users could, for example, install a security system and be able to change from one monitoring service to another without having to install a new system of wires and devices. The service gateway would be an application server in a computer that acts as a gateway between the Internet and a home or small business network of devices. The OSGI plans to specify the API for programmers to allow communication and control between service providers and devices within the home or small business network. OSGIs API will be built on the Java programming language, making OSGI platform-independent. OSGI is an open standard programming interface. Changes will evolve through the Java Community Process. OSGI is intended to connect new Jini smart appliances, Bluetooth wireless device groups, as well as TV set-top boxes, cable modems, alarm systems, energy management systems, and other devices to Internet sites that can be used to manage them remotely and interactively. A service gateway is intended to manage this interconnection with zero administration [22]. OSGI supports a variety of device access technologies, including UPnP and Jini, and is compatible with physical local transports, such as Bluetooth, HAVi, HomePNA, HomeRF, and Universal Serial Bus (USB) [23]. Some device-to-Internet applications are expected to be popular: energy measurement and load management in the home; home security systems that a home owner can monitor and control away from home; continuous monitoring of critical care and home-care patients; and predictive failure reporting for home appliances. The OSGI specification will be designed to complement existing residential standards, such as LonWorks control network [24], CEBus, HAVi, and others. The draft specification version 1 was made available in January 2000 [23]. 4.5.8
Home Plug and Play
CEBus Industry Council is a nonprofit industry consortium aimed to develop and enlarge the market for products compliant with the CEBus Powerline standard or the common application language as implemented in the Home Plug and Play Specification [25]. Members of the CEBus Council include AT&T, Compaq Computer, Hewlett Packard, IBM, Intel, Lucent, Microsoft, Motorola, Panasonic, and Thompson Consumer Electronics. Home Plug and Play (HPnP) is an API standard that sits above the various protocols. It is optimized for the CEBus Powerline bus and can thus
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use the homes 120/240V, 60-cycle, electrical wiring to transport messages for command and control between household devices. HPnP can also use the IEEE 1394 high-speed digital bus. CEBus Powerline carrier uses spread spectrum technology to overcome communication impediments found within the homes electrical wiring. It spreads its signal over a range from 100 to 400 Hz during each bit in the packet. However, instead of using FH or DS spreading, CEBus Powerline carrier sweeps through a range of frequencies as it is transmitted. 4.5.9
Web Programming and Markup Language Standards
Markup languages are the tools for programming Web pages. They incorporate markup instructions into a stream of text. These instructions serve primary purposes: to indicate the structure of a document and to guide the documents presentation. For conventional text documents, structure translates into chapters, sections, and paragraphs, and presentations into elements like color, typeface, and font size. The standard generalized markup language (SGML) is a metalanguage to describe markup languages. HTML
Web programming is one of the keys to create the content needed and is tailored to users needs. HTML, the hypertext markup language, is a world standard. It conforms with the ISO Standard 8879. It coexists with XML and it could be replaced over time by XML and variants of it. NTT DoCoMos i-mode service is built upon a subset of HTML (cHTML) in order to adopt the world standard even for small devices with limited screens and capabilities. HTML tags primarily deal with the presentation aspects of document structures. They do not identify the various pieces of data in the document to support its interpretation and processing. Object technology is a means to add functionality to the Web. It allows Web clients and servers to access other computing resourcesfor example, Java can be added to Web pages and be executed after being downloaded to the client. Dynamic HTML (DHTML) facilities allow HTML documents contents to be treated as a collection of programmable objects. Client-side code can then be manipulated dynamically, changing the document displayed to the user. XML
According to Microsoft, the key computer-industry-led standard that will lead in the future is XML, extensible markup language, a more flexible
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version of HTML. Unlike HTML, it is able to separate data from the presentation of that data. That means the same information can be accessed in different forms on any sort of device without the content having to be rewritten for each. Microsoft points out that XML is the rapidly emerging de facto markup language of the PC-based Internet, and that, due to its flexibility and sophistication, XML will quickly come to dominate on-line services on other devices tooincluding mobile telephones. While HTML defines a fixed set of tags, XML allows the definition of customized markup languages with application-specific tags for representing information. XML defines a data format for structured document interchange on the Web and is a simple subset of SGML. The specifications for structured document interchange are called the XML document type definition. It specifies the application-specific element tags for presenting information that can appear in the document and their attributes. XML is similar to HTML, but allows document formatting. Reformatting for specific devices can then easily be done. It is possible to create documents in XML and convert them into HTML; the extensible stylesheet language (XSL) transformation function simplifies this task. In 2001, W3C presented an improved release of the XML schema. It allows the creation of complex data structures with simple elements. XHTML
The XML-compliant version of HTML is described in a W3C document [26]. This document describes XHTML 1.0 with guidelines to produce HTML-compatible documents that contain proper XML and can be extended to use XML fully in the future. With few exceptions, it strongly resembles HTML 4. It was released in January 2001, upon recommendation of W3C, and represents the most significant evolution of HTML since its introduction. Figure 4.6 (in the following section) shows XHTML basic with its extension for WAP, in contrast to WML and cHTML used in i-mode. XHTML and synchronized multimedia integration language (SMIL) allow developers of Web pages to specify its exact look, for example, the text font and its location in relation to graphics. SMIL was released as Version 1.0 in 1998 and a new version in 2000. The Web composition markup language (WCML) is based on XML and is used for XML to HTML conversion. The markup language initially associated with WAP, derived from XML, is wireless markup language (WML). Unlike XML, it is not
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WML
XHTML XHTMLBasic basic+ +WML WMLextension extension
HTML Subset subset
WSP
HTTP HTTP + p+ush Push
HTTP ++ Simple simple pushPush
WTP
TLS
SSL
UDP
Wireless Wireless profiled TCP TCP profiled
Wireless Wireless profiled TCP TCP profiled
IP
IP
IP
Network NetworkTransport Layerlayer transport
Network NetworkTransport Layerlayer transport
Network NetworkTransport Layerlayer transport
WAP 1.2.1
WAP 2.0
i-mode for FOMA
WDP
2G
2.5G/3G (UMTS)
Figure 4.6 Protocol stack development WAP and i-mode for FOMA.
technologically related to HTML and is therefore unfamiliar to many Internet content developers. The dream of one Internet is helped by XML, which does away with the need to have different Internets for different devicesPCs, mobile telephones, PDAs, digital TVssince it is as suitable for small screens as large ones. cHTML
cHTML is a subset of HTML 3.0 with some additional tags and all those HTML elements that can be represented on a mobile device. The i-mode gateway prepares the Web pages by filtering regular, full HTML Web pages by stripping the elements not belonging to cHTML. This allows access to a number of Internet Web sites in addition to the specifically tailored i-mode ones. The i-mode migration path from the 2G PDC system to IMT-2000/UMTS seems to align with the upgraded XHTML for WAP (see Figure 4.6). WML
The wireless access protocol uses WML, wireless markup language, to display text and icons on the screen of a mobile phone. Instead of point-and-click
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navigation through hypertext, the keypad of the mobile is used. WML is simple to use, although it has limitations when incorporating new modern software. WMLv2 comprises basic XHTML, a smaller version of XHTML 1.0. It is suitable for mobile devices and uses most of the HTML syntax. XSL XSL, extensible stylesheet language, enables users and machines to define display characteristics for different Internet devices. It facilitates the application of presentation styles to any XML document of any particular flavor. Commerce XML This is an open Internet-based standard designed to facilitate exchange of catalog content and transaction information between trading partners. It defines two message protocol models: a request/response model using HTTP, and an asynchronous model with HTTP or URL form encoding. The framework provides security by including authentication information in the message leader. It enables users and machines to define display characteristics for different Internet devices. Procedural Markup Language
In multimedia systems, designers typically link content and presentation. Procedural markup language (PML), a new markup language, decouples content and presentation, thus enabling users to specify the knowledge structures underlying physical media and relations between them using cognitive media roles. This allows in the future a modular design with dynamics, that a given situation determines the appropriate presentation. PML allows truly interactive multimedia systems in which appropriate presentations are created on the fly based on the current interactions and content. Only the knowledge must be specified beforehand. Voice extensible markup language (voice XML) In 1999, AT&T, IBM, Lucent Technologies, and Motorola formed the VoiceXML Forum to establish and promote the voice XML as a standard for making Internet content available by voice and phone [27]. Each company had previously developed its own markup language, but customers were reluctant to invest in a proprietary technology that worked on only one vendors platform. Released in March 2000, version 1.0 of the language specification is based on years of research and development at these companies as well as on comments received from among the more than 150 companies that belong to the Forum. Currently, users obtain Web services from PC with a Web browser that requests and receives HTML documents produced by a Web server.
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Users obtain telephone services with an access device that has audio interaction capabilitiesfor example, a telephone calling an interactive voice response platform that has audio input, output, and its own service logic and transaction server interface. The service logic is typically programmed in a general-purpose language using the platforms API, or a platform-specific scripting language. Although both of these access methods have distinct service logic and transaction server interfaces, it would be advantageous for programming voice services to define a domain-specific language for voice dialogs. Doing so allows an interaction client platform. The platform translates an incoming phone number to a URL, fetches the document, interprets it, and returns the collected input to another URL for processing. The dialog language is voice XML. Voice XML is an application of XML. It is a domain-specific language that defines dialogs between humans and machines in terms of audio files to be played, text to be spoken, speech to be recorded or recognized, and touch-tone input to be collected. Voice XML can describe traditional voice response services as well as newer, mixed-initiative services. The World Wide Web Voice Browser working group has adopted voice XML 1.0 as the basis for the dialog markup language that is part of its speech user interface framework. Voice XML allows the setup of human-to-computer dialogs via a voice browser with audio output in the form of computer-synthesized or recorded speech. Speech recognition allows hands-free text input via a mobile device into a serverthe voice portal. Conclusion
In the mobile sector, where users roam and will access content in different places in the world, compatibility is very important. Thus, the mobile industry has to agree on a common standard related to services and content [15]. It seems that HTML and XHTML will be the main markup languages for the most relevant mobile terminal categories in the near future. Table 4.4 shows them as well as other relevant languages. XML will be used more as a generic language for conversions [28]. Thus, it will mainly reside in gateways, portal platforms, and servers. XHTML will become the language for content development and presentation for mobile business, although XML and XSL may well be the source for XHTML. XHTML, however, cannot do the voice part of mobile portals and so VXML will be needed for such services.
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Table 4.4 Characteristics of Markup Language Standards for Mobile Applications Markup Language
Description
Application
Remarks
HTML
Hypertext markup language
Web Mobile Web 3G laptop PDA
Fixed set of tags, for presentation only, single presentation of each document, text-search only, DHTML for dynamic document manipulation, 3 bio Web pages worldwide
XML
Extensible markup language
Web portals
Extensible set of tags, tags describe data content, multiple use of same document (by XSL), search plus field-sensitive queries + update, enables conversion to HTML, WML
XHTML
Extensible HTML
Mobile Web, 2G3G, Smartphones, PDA
XHTML Basic supported by W3C, XHTML 1.0 is WML extension for WAP (WAP Release 2.0); year of approval: 20012002
cHTML
Compact HTML
Mobile Web 2G/i-mode, Smartphone
Implemented by NTT-DoCoMo, subset of HTML 3.0, 30 million users, Java addition 2001, text, graphics, sounds
WML
Wireless markup language
Mobile Web, 2G/GSM, Initiated by WAP Forum, based on GSM phone XML, text + icons, upgrades to WAP 1.2 offer enhancements
CXML
Commerce XML
Catalog content business transactions
Secure transactions over Internet, mobile application not yet defined
PML
Procedural markup language
Interactive and animation
Content representation flexible, decoupled from content for situation dependent applications
VXML
Voice XML
Voice access to Web, 2G-3G
Proposed by AT&T, IBM, Lucent, Motorola (VXML Forum 150 members), voice-based Web access with voice registration
4.5.10 WAP
WAP is a specification for a set of communication protocols to standardize the way that wireless devices, such as handhelds, mobile telephones, and
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radio transceivers access a network, specifically the Web, to exchange data and to forward and translate method invocations. It enables cooperation and internetworking with the Web for small mobile computing devices. The WAP specification is an industry-established world standard that studies the way in which HTML documents (Internet documents) need to be reformatted and handled for display on cellular terminals. WAP is not a 3GPP, ITU, or ETSI standard. The WAP initiative was founded by the three major mobile handset manufacturers (Ericsson, Motorola, and Nokia) together with Unwired Planet (now phone.com) [29]. Unwired Planet, a California company, developed the handheld device markup language (HDML) as an open Web document language for devices, such as mobile phones (HDML is now called the WML). The WAP Forum [30] aims to address some of the limitations of mobile terminals (such as constraints on power, memory, bandwidth, CPU, and display), as well as some of the limitations of the wireless network environment. Its stated intention is to adapt existing technologies where possible and develop new ones where necessary, ensuring that the benefits of Internet content are made available to mass-market mobile terminals in a scalable and interoperable way. In contrast to regular Web access (as shown in Figure 4.7), WAP uses a gateway to filter and reformat Web-based information. WAP also assumes that mobile phone users will have very different expectations and requirements of the Internet than PC users. WAP was initially specified for 2G (GSM) services and will be upgraded to 3G like i-mode [31]. Essentially, WAP introduces a proxy function between the wireless environment and the standard Web environment. This proxy performs two core tasks: 1. Protocol gateway functionstranslating between the standard Web protocol stack of HTTP/TCP/IP and the WAP protocol stack; 2. Reformatting content using WML and XHTML. WAP also wants to provide users of mobile terminals with rapid and efficient access to the Internet. Therefore, WAP is optimized for both use on the narrowband radio channels used by 2G digital wireless systems and for the limited display capabilities and functionality of the display systems. WAP integrates telephony services with microbrowsing and enables easy-touse interactive Internet access from the mobile handset. With subscriber
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HTML HTTP
Fixed Internet + UMTS
TCP IP
Binary WML
WML
WTP*
HTTP
UDP WAP-GSM
Web server
IP
TCP
Radio
WAP gateway
IP
WAP application server
Gateway functionality compensates for deficiencies of radio link and handset Handsets with higher performance and wireless (profiled) TCP may overcome the need for a gateway. *WTP = Wireless Transaction Protocol GPRS case
Figure 4.7 WAP architecture in comparison with the Internet.
identification, WAP applications include over-the-air e-commerce transactions, on-line banking, information provisioning, and messaging. One concern about the WAP approach was that alternative approaches to HTML reformatting found more sympathy with the World Wide Web Consortium (W3C)the Webs controlling body [32]. The success of i-mode on the Japanese market led to the discussion of new strategies for how to merge and improve both standards in order to adapt them for 3G services. Figure 4.6 shows the protocol stack development towards a 3G-compatible solution between i-mode and WAP. 4.5.11 Smart-Card Standardization
In mobile (cellular and satellite) phones, smart cards increase security and flexibility and speed up personalization with personalized services and data. GSM uses a smart card called the SIM card, and UMTS uses the USIM card to provide storage for subscription- and subscriber-related information. USIM contains an identity, which unambiguously identifies a subscriber, includes all the necessary security, and contains many applications. Multifunction smart cards will allow numerous applications on the same cardfor example, SIM (in GSM), USIM (in UMTS), Europay/MasterCard/Visa
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(EMV; their smart-card specification), common electronic purse specification (CEPS; the future e-purse standard), Loyalty, and Ticketing. The limiting factor for mass-market acceptance of e-commerce is security. As costs of transactions begin to reflect their inherent risks, more secure forms of transactions will be encouraged. Because smart cards offer the required security, they will become interoperable around the world as they are built on generic standards. Industry standards related to smart cards have been defined by the Personal Computer/Smart Card (PC/SC) Working Group, representing Microsoft, IBM, Bull, Schlumberger, and other interested companies, as well as by the OpenCard Framework (OCF) Group. There are two leading smart-card OSs: JavaCard and MultOS. Personal Computer/Smart Card
The PC/SC work group [33] facilitated the development of smart cardbased applications for the PC by developing open specifications that ensure interoperability among smart cards, smart-card readers, and personal computers made by different manufacturers. The PC/SC Specification 2.0 has been available since 2000 and is comprised of the following: • A high-level applications interface to make it easier to build and
maintain smart-card applications; • Programming interfaces (i.e., device drivers) for smart-card reader peripherals connected to a PC; • Specifications for cryptographic functionality and secure storage to be provided by the smart card. OpenCard
OpenCard Framework (OCF) [34] is a standard framework announced by an Industry consortium that provides for interoperable smart-card solutions across many hardware and software platforms. OCF is an open standard that provides an architecture and a set of APIs that enable application developers and service providers to build and deploy smart cardaware solutions in any OpenCard-compliant environment. The OCF provides a common interface for both the smart-card reader and the application on the card. Basing the architecture on Java technology has resulted in enhanced portability and interoperability, which are key to widespread adoption to network computers (NCs), POS, desktops, laptops, set tops, and so on. OpenCard promises to provide 100% pure Java
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smart-card applications. Smart-card applications often are not pure because they communicate with an external device or use the libraries of the client. (As a side note, 100% pure applications could exist without OCF, but without it, developers would be using home-grown interfaces to smart cards.) The version 1.0 reference implementation also enables interaction with existing PC/SC 1.0supported reader devices. The consortium expects to see continued growth of smart-card applications due to this more flexible infrastructure. JavaCard
Java card [35] was introduced by Schlumberger and submitted as a standard by JavaSoft. It is the smart-card platform (OS plus virtual machine) based on the Java programming language developed by Sun Microsystems. Java offers a highly flexible approach to smart-card application management: The write-once-use-anywhere principle and the use of individual applets for each application means that applications can be created, amended, or deleted easily. Java-based smart-card applications that can easily and securely be added or removed from the cards are called cardlets [36]. Because JavaCards enable secure and chip-independent execution of different applications, they ultimately could lead to truly personalized smart cards, where the cardholder could choose which applications to load on the card and could change the applications depending on individual circumstances. Java cards require more memory than other smart cards, and this has an impact on their cost. Transaction speeds are kept as fast as for nonJava cards. For the download, compression techniques are under development. The key benefits of Java card are platform independence, multiapplication capability, post-issuance of applications, and flexibility and compatibility with existing smart-card standardsbenefits that make it the leading smart-card OS. The Difference Between OpenCard Framework and JavaCard
OCF is essentially Java in the computer or terminal talking to the smart card. It is a special, stripped-down version of Java that runs on the smart card itself. Java applications running on the PC can use OpenCard to access JavaCard smart cards and standard smart cards. To write Java applets (cardlets) to run on the smart card itself, a smart card that is compliant with the JavaCard standard has to be used. OpenCard is a host-side application framework for accessing a JavaCard. As is the case with any other smart card, to access a JavaCard, you need a card service that supports the interfaces of the JavaCard applet.
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MultOS
MultOS is a multiapplication smart-card OS, managed by Maosco, a consortium formed in May 1997. The MultOS smart-card OS allows for coresidence of multiple platform-independent applications and allows dynamic remote loading and deletion of applications over the lifetime of a card. MultOS applications are developed using a language called MEL. JavaCard is expected to prevail over MultOS as the smart-card OS. Windows for Smart Cards
This is the smart-card OS developed by Microsoft. As a member of the Windows family, it provides interoperability with any other Windows OS. Although not as popular as the other two OSs, it has gained influence in the industry (e.g., Gemplus, SCM Microsystems, and others). More information can be found at [37]. Smart Cards for Mobile Communication Networks
The standardization in the ETSI Project Smart Card Platform (EP SCP) is concentrating on a common smart card, the UICC, comprising basic functions. In addition, a generic card application toolkit (CAT) is specified based on the USIM toolkit from the UMTS/GSM standard [38] that specifies the interface and functionality of the SIM card. The EP SCP specification gives operators and manufacturers a device-independent platform for developing applications that can be used by the mobile device into which the USIM/UICC is inserted. It allows multifunctional, nonstandardized valueadded services. Developed standards of ETSI are listed under GSM11.x, and of 3GPP under 3GTS 21.x and 31.x. The USIM toolkit functionality is available today in practical form from most major USIM card suppliers. The USIM is the extension of the SIM (GSM); it may incorporate credit card and cash card functions (like prepaid cards) with Bluetooth connectivity and allows user profile download for locally stored applications. USIM Application Toolkit and Generic CAT
As the SAT is a standardized application running on smart cards in GSM mobile phones. The USAT and generic CAT refer to UMTS mobile phones and are the corresponding UMTS standards. Both are more developed and advanced than the SIM Toolkit and offer extended services. CAT includes a PKI platform and application management. Both are described in Section 3.3.4.6.
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MExE
The MExE is the GSM development that aims to provide a standard environment for cellular terminals in which to run enhanced voice and data applications. MExE builds on the desire of operators to develop enhanced services, and on the perception that the Internet is the platform of choice on which to develop these applications. MExE specifies a user environment present in the mobile terminal and a service environment that resides in the network. MExE incorporates two technologies (WAP and Java), and is unusual in that its specification will not be developed entirely by ETSI [39], but jointly with the relevant forums. MExE is an API. It is another way of providing services compared to the USAT. It partners with the CAMEL standard for virtual home environments (VHE). The two technologies, WAP and Java, are part of a twofold approach: • Class 1: Basic MExE based on WAP Microbrowser; • Class 2: Advanced MExE using Java.
The second approach requires more memory, more power, and bandwidth for downloading applets. The advantage of MExE is that it allows, through the support of CAMEL, the same services for the user everywhere when roaming. Table 4.5 shows the main differences between SAT/USAT, WAP, and MExE. Table 4.5 Characteristics of SAT/USAT, WAP, and MExE on USIM Cards SAT/USAT
WAP
MExE
Closed model
Open model
API for terminal
GSM, UMTS
Cross technology
GSM, UMTS
Profile download, application on Application on the WAP server card
Class 1: WAP devices Class 2: Java devices
Limited applications
Scalable applications
Many scalable applications
Integrates with smart card
Integrates with Internet and intranets
Application download
Standard specifications from 3GPP TS 31.x
Standards from WAP Forum
Standards from 3GPP/ETSI
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References [1] Internet Engineering Task Force, The Internet Engineering Task Force Home Page, http://www.ietf.org. [2] UMTS Forum, http://www.umts-forum.org; and UMTS Forum, UMTS Forum Report No. 1, A Regulatory Framework for UMTS, 1012 Russel Square, London WC1B5EE, United Kingdom, UMTS Forum, 1997, http://www.umts-forum.org/ reports.html. [3] IPv6 Forum, http://www.ipv6.org. [4] UWCC, Universal Wireless Communication Consortium, http://www.uwcc.org. [5] IEEE, IEEE groups/802.
802 LAN/MAN Standards Committee, http://grouper.IEEE.org/
[6] IEEE 802.15 Working Group, IEEE 802.15 Working Group for Wireless Personal Area Networks (WPANs), http://grouper.IEEE.org/groups/802/15, August 2001. [7] IEEE P802.15 Working Group, IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs), http://.grouper.IEEE.org/groups/802/15/Tutorials.html, August 2001. [8] IEEE, IEEE 802.11 Working Group for Wireless LANs, http://grouper.IEEE .org/ groups/802/11. [9] Wireless LAN Interoperability Forum, http://www.wlif.com. [10] 3GPP, http://www.3gpp.org. [11] IPv6 Forum, The Next Generation Internet, IPv6 Information Page, http:// www.ipv6.org. [12] UMTS Forum, UMTS Forum Report No. 12, Naming, Addressing and Identification Issues for UMTS, 1012 Russel Square, London WC1B5EE, United Kingdom, UMTS Forum, January 2001, http://www.umts-fourm.org. [13] Tseng, Y. C., et al., Location Awareness on Ad Hoc Wireless Mobile Networks, IEEE Computer Magazine, Vol. 34, No. 6, June 2001, pp. 4651. [14] UMTS Forum, UMTS Forum Report No. 15, Key Components for 3G Mobile Devices, 1012 Russel Square, London WC1B5EE, United Kingdom, UMTS Forum, 2001, http:// www.umts-forum.org. [15] UMTS Forum, UMTS Forum Report No. 16, 3G Portal Study, A Reference Handbook for Portal Operators, Developers and the Mobile Industry, 1012 Russel Square, London WC1B5EE, United Kingdom, UMTS Forum, 2001. [16] MSDN On-Line, SOAP white paper, Simple Object Access Protocol (SOAP) and Firewalls, http://msdn.microsoft.com/workshop/xml/general/SOAP_White_Paper.asp; and Internet Draft of the SOAP specification, http://msdn.microsoft.com/workshop/ xml/general/SOAP_V09.asp, December 1999.
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[17] Object Management Group, http://www.omg.org. [18] Object Management Group, The OMGs Site for CORBA and UML Success Stories, http://www.corba.org. [19] Sun Microsystems, JINI Connection Technology, http://www.sun.com/jini, and The Jini Community, http://www.jini.org. [20] Home Audio/Video Interoperability, http://www.havi.org. [21] The Universal Plug and Play Forum, http://www.upnp.com, and http:// www.upnp.org. [22] OSGI, Open Services Gateway Initiative, http://www.osgi.org. [23] OSGI, white paper, OSGI Specification Overview, Version 1.0, January 2000, http://www.osgi.org/about/specoverview.pdf. [24] Echelon Cooperation, http://www.echelon.com. [25] CEBus Industry Council, http://www.cebus.org. [26] W3C, http://www.w3.org/tr/xhtml1. [27] Voice XML, http://www.voicexml.org. [28] Seligman, L., and A. Rosenthal, XMLs Impact on Databases and Data Sharing, IEEE Computer Magazine, Vol. 34, No. 6, June 2001, pp. 5965. [29] Phone.Com, http://www.phone.com. [30] WAP Forum, http://www.wapforum.org. [31] Hiroshi, N., I-Mode and FOMA Examined: Current Trends and Future Development, Presentation, May 23, 2001 at 3G 2001 Conference, Nice, France, http:// www.iir-3G2001.com. [32] W3C, http://www.w3c.org. [33] PC/SC Workgroup, http://www.pcscworkgroup.com. [34] OpenCard Consortium, http://www.opencard.org. [35] Sun Microsystems, JavaCard Technology, http://java.sun.com/products/javacard. [36] Schlumberger, Schlumberger Smart Cards and Terminals, http://www.slb.com/ smartcards. [37] Microsoft, Smart Cards for Windows, http://www.microsoft.com/windowsce/ smartcard. [38] ETSI, GSM Technical Specification 11.14, Digital Cellular Telecommunications System (Phase 2+); Specification of the SIM Application Toolkit for the Subscriber Identity Module Mobile Equipment (SIM ME) Interface, http://www.etsi.org. [39] ETSI, ETSIStandardizing Telecommunications Products and Services, http:// www.etsi.org.
5 Applications This chapter describes future applications and applications scenarios that are partially new or that make novel use of UC technologies, 3G networks, and mobile computing devices. Benefits are described and technologies for a possible technical realization are proposed. All scenarios make extensive use of the devices and technologies described in Chapter 3, and all create value in the business and consumer service markets. The chapter starts with a description of potential applications of 3G/UMTS networks, proceeds with small information appliances, and concludes with a selection of possible scenarios in the field of vehicle-related mobile computing, health care, telematics, and m-commerce. Ubiquitous and Wireless Networks
The explosive growth of the Internet and especially the Web services in recent years shows that society has a huge insatiable desire for e-mailing and access to information. The extreme popularity of cellular telephones in the past decade underscores the desire of humankind for mobile communication anywhere and anytime. Untethered (i.e., total freedom of location) access to information technology appears to be an idea whose time has come. Yet, in considering this potential for combination of technologies, one must ask what has made the Internet so pervasive in society. The answer should indicate the ingredients necessary to motivate a similar growth in untethered information technology access. Perhaps the most influential items in terms of growth of Internet use have been the convenience of the Web browser and higher access speeds allowed by fast access technologies for networked 299
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personal computers. Convenience at a reasonable cost, therefore, seems to be the necessary combination of characteristics for the widespread embrace of untethered access to information technology. There is also a growing desire for individuality and the ability to personalize products and services. These factors as well will have a significant influence on driving mobile Internet services. The desire to be different and to choose products and services which meet ones own personal needs most effectively manifests itself in the demand for personalized services. Throughout the retail and service industries, there is a trend towards giving consumers control of defining the product or service to meet their personal choice or need. This is valued by consumers as it extends choice, saves money (in many cases) and saves timeswith the subsequent improvement in quality of life. Therefore, it is expected that the growth in demand for interactive entertainment and information services combined with m-commerce will be driven by this trend, provided service providers can give the consumer control of customizing services, and that this control is made easy by simple design of delivery mechanisms and interfaces. Networked Multimedia Services in the Corporate Sector
A number of industries are experiencing the beginnings of a paradigm shift from work focused on a static, central location with long-term employment contracts, to more flexible business units where the workforce is more mobile, both in terms of where they work and who they work for. Progressive companies within these industries are already attempting to streamline their organizational structure and to adopt more flexible working arrangements with their staff by experimenting with new concepts, such as outsourcing functions, virtual project teams, and teleworking, in order to cut costs, increase productivity, or create competitive advantage through increased responsiveness to market trends or customers needs. Companies may expect the following from widespread wireless access to information technology: • Any individual can participate in on-line education programs
regardless of geographic location, age, physical limitation, or personal schedule.
• Any individual can contact servers and databases, can by guided by
portals to the information needed, and can communicate independently from its location (e.g., for entertainment and games).
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• Any company can be easily reached by its customers, regardless of
location.
• The workplace is no longer confined to a specific geographic loca-
tion, as workers can easily access their tasks and colleagues from alternate locations or while en route. A highly flexible workplace is able to accommodate each individuals needs, from working parents to workers with disabilities.
• Telemedicine applications are commonplace. Specialists use video-
conferencing and telesensing methods to interview and even to examine patients who may be hundreds of miles away.
• Complex products and structures can be designed via computer
simulations that accurately represent the physical properties of the systems being built.
• Research is conducted in virtual laboratories in which scientists and
engineers can routinely perform their work without regard to physical location.
• Government services and information are easily accessible to citi-
zens, regardless of their physical location.
Potential services and applications and uses of high-capacity tetherless communications systems in vehicles, traffic, and management include the following: • Virtual navigation: A remote database contains the graphical repre-
sentation of streets, buildings, and physical features of a large metropolis. This data is transmitted to a vehicle or person, where a rendering program permits the driver to visualize the road ahead and become acquainted with it. They may also virtually see a photograph of the building they intend to enter and possibly see the internal layout of buildings to plan an emergency rescue, to virtually visit museums and monuments to decide if a stop and visit is warranted, to find restaurants and preview menus, to find bathrooms, and so on.
• Telemedicine: The paramedic assisting the victim of a traffic accident
in a remote location must access medical records (e.g., X rays) and may need video conference assistance from a surgeon for an emergency intervention. In fact, the paramedic may need to relay back to the hospital the victims X rays taken locally.
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• Infostation: An automobile driver may retrieve a full load of files and
multimedia material from the network while driving on the freeway as he or she passes by an infostation. High data transfer rates are essential for the limited time window at highway speeds. For long distance information supply, wide area 3G networks allow 384 Kbps while traveling at highway speeds.
• Location-dependent applications: The combination of geographical
information systems (GISs), GPSs, and high-capacity wireless mobile systems (3G) will enable a new type of application referred to as telegeoprocessing. Queries dependent on location information of several users, in addition to temporal aspects, have many applications. For example, a group of researchers collecting biodiversity data in the South American rain forests may wish to cover a geographic area while concentrating on areas with the most severe decline in a species. They can upload their observations to a remote database with the GPS providing their location and pose a query: Where should I go next, and what species do I need to track? After processing the data from the research team, each member would receive instructions on how to proceed with the survey.
• Crisis management applications: These arise, for example, as a result
of natural disasters where the entire communications infrastructure is in disarray. Restoring communications quickly is essential. With wideband wireless mobile capability, an infrastructure for low and high bandwidth communications, including Internet and video services, could be set up in a matter of hours as opposed to days or even weeks required for restoration of wireline communications.
• Education via the Internet: Educational opportunities available on
the Internet, both for pupils, students, and individuals interested in life-long education, are unavailable to clientele living in thinly populated or remote areas because of the economic unfeasibility of providing wideband wireline Internet access in these areas. Wideband wireless communications provide a cost-effective alternative in these situations.
• Computer- and network-aided remote collaboration: A design team
collaborates in the design of a car, for example. Some of the team members may be on the road, waiting at the airport, or driving their cars. They are connected via videoconference and transmit videoclips, images, and other multimedia data to each other via multicast.
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• Neighborhood access: High data-rate wireless connections can pro-
vide rapidly deployable wireless voice/data/video connections to the home, thus providing increased cost-effectiveness over wireline connections for widely scattered country estate residences, to say nothing of the 30% of the worlds population living in apartment buildings.
Networked Vehicle Intranet
Networked vehicle intranet, mainly using vehicle-based Intranet solutions, is something for both commercial companies and security companies. In addition, the U.S. Army Tank-Automotive and Armaments Command (TACOM) is interested in applications [1]. Vehicle-based intranet technologies, based on mobile computing technologies, will enable and facilitate the flow of information throughout the vehicle and between it and ancillary support services. This includes seamless interoperability with future logistics and intelligent transportation systems. The vehicle-based intranet technologies are also directly applicable to consumer markets for electronics, automobiles, and information services. Such developments already exist (e.g., the smart car) and are taking place in the commercial sector, like the commercial network vehicle called the network vehicle concept car [2]. Networked vehicle intranet emphasizes the following key technologies: • Vehicle application download from the Internet; • Embedded vehicle and server-side diagnostics, prognostics, and
monitoring; • Distributed component computing; • Secure multithreaded information exchange between onboard systems and vehicle operators. Ad Hoc Networking in the Public Domain
Ad hoc networking will be an issue for the future. It probably starts in relation to a person who wants to get information from his environmentfor example, from a computer or an information desk if the person enters a certain environment. Other examples can be where vehicles are communicating with each other as they are driven, continuously changing the communication relation along with their traffic behavior, or they communicate with gas stations, hotels, and restaurants if they are leaving or entering a certain environment or situation.
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5.1 UMTS Services and Applications Numerous articles, reports, and documents are available that discuss 3G mobile services and applications in the IT environment. Yet, in nearly all this literature, you find no clear definition of the two terms. Service and application are often used interchangeably, even within the same document. A concept like m-commerce will be classified as a service in one report and as an application in the next. The terminology serves to confuse rather than clarify. Thus, the UMTS Forum has formulated an industry consensus for the understanding of 3G services and applications. These so-called definitions can be found in [3] and are summarized as follows: • Services are the portfolio of choices offered by a service provider to a
user. Services are elements that service providers may choose to offer separately or in a package.
• Applications are the building blocks that enable the creation of
services. Content is the information the users want. Devices allow a user to interact with the application in order to access and use the content.
Under these definitions, m-commerce will most commonly be an application rather than a service. More strictly, it will be the combination of a large number of applications (e.g., security, certification, transaction recording and interchange, application execution environments) that an operator deploys to enable a range of services. The UMTS Forum expects that by 2010 nearly 50% of all Internet users will access the Internet from two or more devices including mobiles. In the following, an overview is given on the six service categories identified in the UMTS Forum [4]. Table 5.1 shows application examples allocated to these six 3G service categories. 5.1.1
Mobile Internet and Intranet Access • Mobile Internet access: A tunnel service that offers mobile access
to full fixed ISP services. It includes transparent Web access to the Internet as well as file transfer, electronic mail (e-mail), and streaming or download of AV.
Applications
305
Table 5.1 3G Services and Applications 3G Service Categories/ Applications
Internet Access
Intranet Access
Customized Infotainment
Multimedia Location- Rich Messaging Based Voice
Speech
X
Videotelephony
X
Videoconferencing
X
Office extension
X
X
Remote monitoring X
X
Experts on call
X
X
Games
X
Education
X
X
X
Image transfer
X
X
X
Audio streaming
X
X
X
Video streaming
X
X
M-banking
X
M-commerce
X
X
Telemedicine
X
X
Mobile chatting
X
Telemetry
X
X X
X
X
X
X X
X
X
X
X
X
X X
X
X
X
• Mobile intranet and extranet access: A tunnel service that provides
transparent secure mobile access to corporate LANs and VPNs.
Mobile Internet access is for business users as well as for residential users. It will be provided via tunneling to the respective server or source (e.g., to an ISP or Internet portal). This service will be highly important for m-commerce so that end-to-end security availability can be assured. This service also provides the convergence between wireless UMTS and the fixed Internet. For the business user, mobile intranet access will act as a tunnel access to the Intranet of an organization. The main application will be the office extension. The external actors of a company or organization will have
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managed access to the intranet in the way of a mobile VPN. This VPN will integrate the wireline intranet usersit is a combined wireless and wireline network. E-commerce will be a driving factor for this service category. The emerging demand for teleworkers and office solutions in vehicles are indicators for such developments. Figure 5.1 shows the interest of workers to participate in teleworking in Western Europe: 5.1.2
Customized Infotainment and Edutainment
NTT DoCoMos i-mode service experienced an impressive huge market development in the business and consumer segment since the Internet has been going mobile. Customized infotainment is understood as a variety of services and applications regarding entertainment, e-shopping, gaming, and education. It is a 2G-3G service that provides mobile access to customized content, tailored mainly to handhelds and PDAs, and based on mobile portals. Audio and video download or streaming will be included under the brand FOMA. The i-mode example has also shown that people are using their downtime for entertainment on the go and that they are willing to pay for such services. These services are accessed by using mobile portals 50% of the time. This fact is a major opportunity for 3G operators to extend their Interest in teleworking 7
6.7
6
5.3
5
4.5
% 4 3
2.6
2.3
2
2.1
2.4
2.1 1.6 1.4
1.5 1.5
1 0
1.2 0.8
FIN
SW
DK
UK
I
Teleworking at home Teleworking on the move Figure 5.1 Interest in telework. (Source: Gareis/empirica GmbH.)
D
F
Applications
307
business model. Mobile portals encourage loyalty through the ability to personalize the selection of available content and commerce capabilities. Although i-mode was limited in the first years regarding the access bit rate, it has now reached mass-market success. I-mode is improved with 3G and will provide audio and video applications. The portal is a key element in the value chain. WAP also uses mobile portals. (The market success of i-mode is shown in Figure 5.7.) Information and entertainment were and still are driving factors in the information industry (e.g., radio, TV). In the past, unidirectional broadcast services were the sole distribution means for the media industry. Pay-TV and digital TV will allow limited individual selection of information. A new type of person-related information delivery will begin with UMTS: Worldwide roaming users will be able to listen to their home radio stations or view the TV channels they prefer regardless of their location on the globe. Acceptable quality levels can be achieved with reasonable tariffsfor example, individual UMTS FM radio reception can be provided with an approximately 100-Kbps streaming mode. Games and remote gambling are attractive for commuters sitting in the train for quite some time. Microsoft and Intel have cooperated to develop mobile games. Travel and tourism will be offered a great new opportunity to show the special offers via a mobile Web page. Last minute offerings can be communicated to far more people then with advertising today. Regarding education services, the Internet has enabled remote learning. With mobile access, new opportunities to learn will be deliveredboth time and location independent. 5.1.3
Multimedia Messaging Services
More than 50 billion short messages were sent over the worlds GSM networks in the first quarter of 2001, with an estimated 200 billion global messages for the year. The SMS is generally a person-to-person delay-tolerant service. It still is the most popular data service in 2G networks. In 1996 when the service was started, the German D2 network operator counted 21 million SMS. In 2000, the figure was 7 billion. It is no wonder that combinations with voice, fax, and e-mail were brought to the marketplace, known as unified messaging. The possibility of providing chat services on top of SMS and location information about friends in the area of the user, opens up new opportunities, especially with 3G where photographs and other information can be added. The expected enormous growth of mobile messaging indicates the
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importance of SMS, EMS, and the MMSs. Figure 5.2 shows the authors view on the market development towards multimedia messaging. National and international interoperability of messaging services between operators and different networks, coupled with enhanced information services, has driven market acceptance and traffic growth. Messaging services for interpersonal communication include basic SMS, unified messaging, and MMS. Basic test messaging services were launched in 1996 and are now extremely widespread worldwide. SMS in GSM networks allows mobile users to send and receive messages of up to 160 characters. The broadcast mode for sending SMS to a group of users entering a location area, or to a chat forum, provides information that is area specific. Also, sending and receiving short messages from a mobile to a computer and vice-versa, including conversion into or from e-mails, fax, and the like, is the de facto standard today. With 3G, higher bit rates and the always-on characteristic enable the combination of media for messaging capability. The high data rates available will also add image and video capability to create a multimedia messaging service. These capabilities are described as follows: • Messaging services: Information exchange with short transport delay
and always-on. The information can be a text message with or without images and tones.
Messages per month (billion)
70 60
MMS
50
EMS
40 SMS
30 20 10
2001
2002
2003 2004 Year
2005
2006
Figure 5.2 Worldwide growth of SMS, EMS, and MMS in GSM and UMTS networks.
Applications
309
• Multimedia messaging: The information exchange combines digital
images (JPEG), graphic inserts, and in the future AV downloads or streaming (MP3, MPEG-4).
Unified Messaging
In addition to SMS, the unified messaging services (UMS) were introduced in the mobile market. Unified messaging will evolve to MMS in the context of UMTS. Unified messaging results from the interconnection of the various messaging systems, which support vocal messages, e-mail, fax, and SMS. This service encompasses conversion of SMS into e-mails and possibly consulting an e-mail inbox, which is opened by the mobile operator, from a mobile phone, thus unifying all messages irrespective of medium of origin. Consultation is performed in on-screen display mode for the first 160 characters or by vocal reading. Enhanced Messaging
In May 2001, Alcatel, Ericsson, Motorola, and Siemens agreed that they would implement EMS and work together to ensure interoperability between their products, as well as in the evolution of the EMS standard within the 3GPP standardization. As the name implies, EMS enhances the SMS service. It adds powerful new functionality to the text-based SMS. Using EMS, mobile phone users can add life to their text messages in the form of images, melodies, and animations. Users are able to enjoy collecting and swapping images, ring signals, and other melodies between the handsets of some of the worlds leading suppliers. Because the EMS standard is open, operators and content suppliers alike will be able to introduce appealing new value-added services, such as screen savers, images, and ring melodies that can be easily downloaded from the Internet. EMS messages are sent over the same infrastructure as regular SMS messages, allowing for quick and easy deployment of individual applications. EMS provides an important evolutionary step between SMS and full MMS. The EMS standard was defined by 3GPP in 2001. It is a completely open standard that may be supported by any manufacturer in the interests of interoperability between consumers. Instant Messaging: No Longer Just Chat
The instant messaging service originated in 1985 when America Online (AOL), called Quantum Computer Services at the time, bundled lists of
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UMTS and Mobile Computing
contacts with its proprietary service [AOL Instant Messenger (AIM)]. AOL is currently the market leader in the Internet, followed by Yahoo and ICQ. Along with the upcoming UMTS, Internet and intranet access will open up to the user an opportunity for a wireless instant messaging service. To most users, instant messaging is just a casual chat service: the two key elements are messaging and presence detection, which tells users which members of their list of contacts are signed on. The service coexists with SMS, UMS, and probably in the future also with MMS. An increasing number of cellular operators are offering wireless access to instant messaging, and it is also included in the WAP service. Multimedia Messaging
This is the final evolutionary step. The concept differs from SMS, as it is based on the all-IP approach of UMTS. Thus, it will be able to deliver longer messages and multimedia. Its standardization is part of the 3GPPs work. Multimedia messaging must be considered as converged applications and could be therefore quite complex. Innovation of technology will enable mobile terminals with expanded memory and enhanced processor performance and with large screens and vocal recognition to support new features and combinations of images, audio, and video with text messaging. The progress to rich media could be favored through the implementation of customized portals, dedicated to each customer. The forecasts are high: Operator revenues will rise to more than US $40 billion worldwide in 2010. Figure 5.3 shows regional revenue forecasts for multimedia messaging services published by the UMTS Forum [4]. Multimedia messaging merges different types of messages from different senders to one receiver. It integrates different addressing, and it provides confidentiality and security. 5.1.4
Location-Based Services
Position information about users (person or device) with 3G adds a new dimension to this service category. Location technology not only enables specific location-based services, but also enhances other service offerings, such as customized infotainment, and will be a major driver for the creation of new applications. For 3G networks, standards are in progress in order to achieve a global roaming capability related to these services. A location-based service is a business or consumer service that enables users to find location-dependent content (e.g., hotels, restaurants, other people, vehicles, or machines). It also enables others to find users, as well as enabling users to identify their own location via terminal or vehicle
Applications
311
18
Service revenues ($ billions)
16 14 12 10 8 6 4 2 0
2005 2010 North America Consumer
2005 2010 Asia-Pacific
2005 2010 Europe
2005 2010 Rest of World
Business
Figure 5.3 Forecasted MMS revenues by region, 2005 and 2010. (Source: UMTS Forum.)
identification. Emergency services will belong to this category in the future. A location service example is shown in Figure 5.4. The home pages deliver the content. It is obvious that the Web is specifically involved for the benefit of the roaming user. Its content is everywhere, regardless of relevance. On the other hand, wireless networks lead naturally to the exchange of information relevant to the location of each terminal. By capturing the location of the user, the networks will be able to provide real-time information and services that will increase the revenue generating potential. Often-cited examples include issuing coupons for immediate use when you pass by a store, obtaining upcoming road condition and traffic reports, and obtaining the names of restaurants in a particular area (and of course, you can then obtain a review from your favorite restaurant critic off the Internet)and, with one touch dialing, you are connected. The following list shows some service examples: • Location-based billing with attractive home-zone tariffs; • Information filtering dependent on users location; • Navigation, reservations, and ordering depending on users actual
location;
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UMTS and Mobile Computing
Connect to WAP server
Local homepage of selected restaurant
Receive reservation options from server
MobilNet Restaurant finder Local specials
MobilNet Restaurant finder Trattoria Bruno Via Giuseppe 23
MobilNet Trattoria Bruno Table reservation
French McDonalds
Give directions
Submit e-mail Show status ...connect
OK
OK
Taking into account of client, server accesses restaurant data base
WAP server returns contents of selected page
Receive incoming call from network
MobilNet Trattoria Bruno
OK
OK
Between restaurant and client
Figure 5.4 Location-service example. (Source: Siemens.)
• Home, local, or travel information depending on users actual location; • End user assistance servicesthese are low-usage services designed
to provide end users with safety networks for difficult situations, such as roadside assistance and emergency services;
• Monitored person locationthis includes data for health care,
emergency calls, and prisoner tagging;
• Third-party tracking services for both corporate and consumer mar-
ketsinformation regarding the location of a third party is provided for use in fleet management, asset tracking, and people and car finding;
• Trigger services are automatically initiated when end users enter
a predetermined areaexamples include location-based billing and advertising services;
• Games dependent on the location of the persons involved. Mobile Location Technologies
The ability to locate a mobile devices position is key for providing geographically specific, value-added information that stimulates m-business. Various technologies will become available to provide such services. One
Applications
313
existing system is called Locus [5], which is deployed over the PHS wireless phone system in Japan. The cell of origin (COO) method is the simplest method available today. It is already used in WAP applications. Network operators are able to correlate phone numbers with the network cell to which a device is connected. Depending on the cell size, sensing accuracy ranges between a few hundred meters to a few kilometers. Location-based billing is using this method. The more accurate location fixing scheme (LFS) was standardized by ETSI in 1999 and will penetrate the mobile market within the next 2 years. This category includes GPS, time difference of arrival (TDOA), and enhanced observed time difference (EOTD). These methods provide a location sensing accuracy of 20 to 150m. In addition to these technologies, which more or less require device or network modifications, other approaches have been developed that are handset-based and that operate on a standard GSM network with a precision range of 200m. It is still too early to tell which of these will be successful or will dominate the market. The COO method is presently in use by some operators mainly for location-based billing. In October 2001, the U.S. operators AT&T and Cingular made public that they decided to use TDOA for their networks. The success of these technologies will strongly depend upon the industry agreements on a common set of protocols and solutions for positioning. One example is the Coordination Group on Access to Location Information by Emergency Services (CGALIES); its task is to explore implementations of E112 emergency services in the European Union on an EOTD-GPS hybrid solution. A similar initiative exists in the United States (FCC E 911 Project). Further information can be found in the UMTS Forum Reports [6]. GPS
GPS uses 24 GPS satellites orbiting the Earth at an altitude of approximately 18,000 km, and by means of a triangulation process, it accurately measures on the L-band frequencies (L1 = 1,575.42 MHz and L2 = 1,226.6 MHz) of any position on the planet. The satellites transmit navigation messages that contain their orbital elements, clocks, and statuses for the GPS receiver for positioning and roaming speed. Using more satellites than three increases the accuracy and the altitude of the receivers. The accuracy is usually in the order of a few tens of meters. Currently, there is no charge for the use of these GPS satellites [7]. The GPS solutions will require additional chip sets for handsets and coordination with the wireless. This will mean incremental handset costs and increased power usage at the handset level. Other drawbacks include the
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UMTS and Mobile Computing
inability to function well in valleys, among trees, or in tunnels or dense urban areas, although new technologies are working on solving these problems. The GPS satellites are controlled by the U.S. government [8], which, until recently, intentionally scrambled civilian GPS signals to reduce the accuracy to 65m instead of a theoretical 5 cm or less. The GPS solution is more accurate than network solutions, and with new GPS technologies some of the line-of-sight problems could be eliminated. The European Galileo satellite positioning system will go into service in the near future. It works within satellites and is similar to the existing GPS. Other systems are the assisted GPS system Snap Track of Qualcomm. Terrestrial Network Technologies
Terrestrial-network-based technologies are cheaper and quicker to implement, but are less accurate. Cambridge Positioning Systems may offer the best conceptual and practical technology in this area. Unlike the triangulation patterns (three cells) needed by TOA or TDOA in order to calculate positions, location pattern matching uses only one cell site to arrive at a location. US Wireless has been in trials by several of the larger U.S. carriers. Cell-Loc has been in trials in Canada, Brazil, and other international designations (see Figure 5.5). In the short term EOTD will be implemented, but in the longer term GPS technologies could become cheaper and more accurate in urban areas.
Application server
LBS* server
Mobile device transmits radio signal.
Signal arrives at the base station via multiple paths.
Unique characteristics of the signal multipath content are analyzed; signature pattern is compiled.
*Location-based services
Figure 5.5 The location pattern matching process.
Signature pattern is compared to a database of previously corresponding signature pattern; a match is made in order to identify the nearest restaurant, park, or garage, for example.
Applications
315
The forecasts from 2001 from the UMTS Forum shown in Figure 5.6 for location services were made with support from Telecompetition, USA. They are on the order of several billion U.S. dollars predicted for 2010. 5.1.5
Voice- and Videotelephony and -conferencing
Voice will inevitably continue to be an important service offering in the 3G environment. High data rates will allow the addition of videophone capabilities to traditional voice services (rich voice). The IP environment of 3G will allow the delivery of multimedia communications within the voice service. Voice, video telephony, and video conferencing services, which are realtime and two-way, also provide advanced voice capabilities including VoIP, voice-activated net access, and Web-initiated voice calls. As the service matures, it will include mobile videophone and real-time multimedia communications. Voice will be delivered as a real-time interactive service with short and constant delay throughout the networks. UMTS can provide voice with the same high quality as it is offered via ISDN networks; adaptive multirate
Service revenues ($billions)
4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0
North America Year 2005
Asia-Pacific
Europe
Rest of World
Year 2010
Figure 5.6 Worldwide location-services revenues forecasted by region. (Source: UMTS Forum.)
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UMTS and Mobile Computing
codecs allow qualities dependent on users choice and acceptance. The total number of voice service subscriptions is forecasted by many market researchers to be up to 2 billion and beyond in 2010. Videotelephony requires bit rates of at least 64 Kbps in real-time mode. This was experienced in NTT DoCoMos 3G service FOMA. The demand for such a service including videoconferencing is not yet known. 5.1.6
UMTS Services Portability
As it is expected, the mobile user or device is roaming worldwide; thus, Internet services offered have to be accessible from the user anywhere, independently from the visiting network. The user may have a personal service profile, which is used in mobile portals offering personalized multimedia services. As a consequence of such a requirement, a service creation environment is under discussion whereby new services (often Web-based) can be devised and introduced by third parties. In order to meet such a vision, new organizations and technologies will be involved in the process of creating services. It is planned that the users home network, together with users personal profile, should manage the services. These should, as far as possible, be maintained even when roaming to other networks. This concept has been named the VHE, since the intention is for the user to always feel that he is on the home network. VHE
VHE means the delivery of service providers total environment, especially the corporate intranets virtual work environment, to the user at all times wherever it roams in whichever network, public, private, satellite, mobile, or fixed. It is likely that the terminal will negotiate with the visited network and the home environment automatically on switch-on, possibly even downloading software so that it will provide home-like service, with full security through its smart card. Charges for connection and use of the services will be presented immediately, clearly, and simply. The following lists some VHE requirements: • Seamless service access from the users perspective (global availabil-
ity, access network independent, common service control and data);
• User and service provider personalization (create and run services,
user and service providers same look and feel) provides personalized application bundles;
Applications
317
• Supports services from different systems; • Provides a common framework for service delivery and control in
future networks;
• Enables service provider differentiation.
New Roles in UMTS
New organizations will play a part in the delivery of 3G services, including service providers, content providers, and service brokers. In this instance the service providers will be more like ISPs than todays airtime resellers. Content providers, or value-added service providers, will generally provide niche services through a service providertodays examples include banks, news agencies, travel agencies, software houses, publishers, retail outlets, university departments, government organizations, as well as thousands of individuals. Many of the services already offered have been innovative, often using unique downloadable software applications. Corporate intranets will, in effect, be one of the most important service providers. UMTS will give them the opportunity to extend their IT environments to their staff while they are traveling and off site, through the VHE feature. Service brokers are expected to appear as well in response to the increasingly diverse sources for telecommunications. They will be able to provide their customers with a one-stop shop for telephone, mobile, Internet, paging, and more, including possibly subscription TV. In turn, they will negotiate package deals with network operators and service providers so that they can offer a comprehensive set of services with one billing point. There is frequently a great deal of confusion within the industry regarding the definition of a mobile virtual network operator (MVNO). The strict definition states that MVNOs must own a switching center and other infrastructure. It is interesting to note that in using this logic a business is defined by the technology and equipment. If we were reviewing the automotive industry we would not specify that the car manufacturer should have a certain level of equipment, technology, or manufacturing capability. We would define it as a company that designs and supplies cars. How the car company decides to produce the cars and how much it decides to subcontract is entirely up to the company itself. Frequently, the car production company outsources the manufacturing component and undertakes the assembly, but this itself is becoming more difficult to define as assembly is undertaken more and more by component suppliers.
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UMTS and Mobile Computing
In 3G, the MVNO will be an entity that operates independently of the operator and has the ability to set its own services and tariff structures but relies on the operators infrastructure for subscriber management and also for its radio network.
5.2 Examples: WAP and i-Mode In 2G mobile networks, there were mainly two Internet-related services developed: WAP and i-mode. Both developments were focused on the same target: to build a wireless Internet solution tailored to mobile phones with limited capabilities. NTT DoCoMos i-mode has become a mass-market success within the time frame of less then 2 years, providing Internet access from mobile phones. From 1999 to 2001, it has outpaced WAP. The fact that i-mode is neither high speed nor provides Internet access from the beginning (it started as an intranet and provided Internet access via proxy servers) did not matter to the market. It was successful because it started as a branded, easy-to-use service with a markup language that is a subset of HTML. It is perceived to be high speed with 3G because it is packet-based and is making use of WCDMA, the UMTS radio access that allows higher bit rates. WAP has been released on circuit-switched networks. Although using the same bit rate as i-mode, it was perceived as a clunky, slow service. It was, in fact, a branded technology, not a service. WAP users on different networks have had access to different content. With respect to information delivered to the phones, WAP uses WML to display text and icons on the mobile phones screen. Instead of point-and-click navigation through hypertext, people use the phones small keypad to send information upstream for receiving content. WAP functions well in the low-data-rate, low-power environment of present cellular systems. On the other hand, it suffers from several deficiencies relative to the Internet. Figure 4.7 shows the differences between fixed Internet Web access and WAP. WAP gateways rewrite everything that passes through them. This includes the processing of the document itself. WAP is a good mechanism for accessing specifically tailored content and services, some of which will arise from the Internet and the Web. Web pages are full of graphics and advertisements, and because of the high bit rates at which fixed networks operate, users can browse at their leisure, surfing for the information they require. Illustrations, graphics, and banner advertisements would not only be very difficult to view on a mobile screen,
Applications
319
but the physical limitations of the GSM network and on the terminal mean that a different approach has to be taken to the service and content design. Simply repurposing Web content is not good enough. A current view of mobile technology analysts is that WAP services are best suited to transacting rather than browsing: receiving e-mails, locating an Indian restaurant in the vicinity, finding out whats on TV that night, or checking lottery results. Already, the majority of mobile handsets have built-in WAP browsers, which will provide XHTML capability beginning in 2002. The WAP solution is composed of five elements: 1. A WAP-enabled phone or terminal that has a built-in microbrowser allowing it to communicate with a WAP service; 2. Application software; 3. A WAP application server, on which the application resides, usually at the ASPs premises; 4. A remote access server that acts as a point of presence site to the Internet; 5. WAP gateway (see Figure 4.7), which converts WAP to IP so that data can pass between the WAP phone and the WAP application server. There are two types of WAP gateways, depending on how sophisticated the ASPs requirements are. The entry level WAP gateway provides access to ASPs content servers from any WAP device. A managed WAP gateway enables corporations and ASPs to develop mobile-enabled end user propositions for their own customers. With the arrival of 2.5G and 3G, the WAP Forum released in 2001 its specifications for WAP 2.0. A total of 55 different specification sets are included in this version, which is bringing together WML-based services with cHTML-based services. WAP 2.0 will further include cascading style sheets, transport layer security, HTTP, and TCP (see Figure 4.6). In the future, the standard will also include multimedia messaging services combining sound, video, and text. Interoperability with the 3G FOMA service of NTT DoCoMo [9] is provided in such a way that WAP 2.0 content is identical on the screen to a large extent, with minor form deviations. The name FOMA expresses the concept of content access anytime and anywhere, in a 3G mobile environment based on wideband CDMA technology. FOMA is the brand name for NTT DoCoMos 3G services; it is an acronym for
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UMTS and Mobile Computing
freedom of mobile multimedia access. A number of multimedia services will be introduced under the FOMA brand. Both i-mode and WAP are examples of one approach to the marketthe approach of extending mobile phones into the data and computing environments. This approach is targeted at the moving mobile (rather than the portable) environment and seems to be favored by mobile terminal manufacturers. The alternative approach is to extend portable computers to become mobile communication devicesan approach more favored by some U.S. manufacturers. This approach is targeted more at mobile access to the Internet or intranets. Both approaches will coexist for some considerable time. In the short term, this could lead to some polarization in market perceptions of 3G as adding mobility to computing devices. The success of i-mode justifies a brief description of the service, especially since it is driven forward for 3G improvements. It includes voice calls, e-mail, and Web site access. An i-mode phone with a cHTML browser connects to NTT DoCoMos Intranet through a 9.6 Kbps (in 2002: 28.8 Kbps) packet-switched network (PDC). Its upgraded version for the 3G FOMA service (which provides voice, videophone, and other data services) provides more capabilities, as it is based on higher bit rates, up to 384 Kbps. The i-Mode Example
By the end of 2001, Japan had about 70 million users of cellular phones, including PHS, and about 40 million are using browser phone services, such as i-mode, EZ Web, and J-Sky. In February 1999 the Japanese mobile operator NTT DoCoMo started a cellular, packet-based data service called i-mode, and now approximately 50% of NTT DoCoMos cellular subscribers use the i-mode (see Figure 5.7). The service was upgraded in 2001 for 3G mobile applications under the NTT DoCoMos FOMA service [9, 10]. The i-mode concept sticks as close as possible to the Internet standards. It converts the underlying protocol and passes its content through. i-mode is first of all an intranet solution. In 2001 it had more than 650 alliance partners, which have over 1.6 million i-mode Web sites and 600 search engines to find information. Also, 44 million general Web sites can be accessed (Yahoo, Infoseek, Lycos). Content is provided in a number of fields, mobile trading and mobile banking, with more then 300 banks. A subset of cHTML is applied in order to facilitate the production of Web pages and to ease migration to 3G with transparent HTML Web services. Java technology allows feature download, and other tools allow end-to-end security for m-commerce. With the launch of 3G services in 2001, NTT DoCoMo
Applications
External extension
i-Mode users (millions)
25
Colored LCD
Rich (visual, high speed)
Music
Intranet packages
15 i-Mode launch
Intranet Video Game
Groupware Schedule management Workflow management Electronic bulletin-board system . Electronic conference File sharing
Web access
Security function
Car navigation
5 0
IMT-2000
Java technology and SSL security
20
10
321
E-mail
Agent function
Homepage
February 1999
2000
Year
2001
Mobile TV
Portal link
2002
Figure 5.7 i-Mode for infotainment and m-commerce. (Source: NTT DoCoMo.)
provided new multimedia terminals with richer content possibilities, as well as audio and video downloads. The start of the service in 1999 was with only 67 application alliance partners. As the number of subscribers increased, the content providers offered more content. The voluntary i-mode Web sites and the increase in corporate use is a positive feedback process of i-mode. One can buy airline or concert tickets, books, CDs, and games. One can also buy animated pictures and ringing tones for customizing the handset, horoscopes, restaurant guides, such as ZAGAT, and news including CNN, Bloomberg, and Dow Jones. Weather forecasts are also available. Mobile banking is provided by more than 300 banks including CitiBank. There is also mobile trading, on-line stock selling and buying. i-Mode Subscriber Numbers
The penetration rate of cellular phones in Japan was over 50% by the end of 2000. Again, 50% of this market base have i-mode capability. It took 6 months to acquire the first 1 million subscribers for i-mode, but there were 100,000 subscribers added every week. The number of subscribers increased dramatically and reached 5 million subscribers in March 2000and by the end of 2001 there were nearly 30 million users.
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The user pays a basic subscription fee of ¥300 (∼US$3.00), and pays additionally for each packet of data, rather than the time spent on-line. Currently, one packet of 128 bytes of data is charged at a rate of ¥0.3 (∼US$0.003). The handhelds are subsidized by NTT DoCoMo: the user pays $130 for the subscription and a handheld with color display and Java capability. DoCoMo then provides via its packet network a gateway server, which is a proxy server with no conversion, to allow access to the Internet. The protocols are all based on the Internet standards of HTML and HTTP. One can access content through the i-menu portal. First, it is information, such as news, weather, and sports. Second, it is transaction services, such as mobile banking, securities trading, and ticket reservations. Database information, like restaurant guides, recipes, and the yellow pages telephone directory come apart of this group as well. Entertainment content, like cartoon characters, are downloadable, as are network games, ringing-tones, and karaoke information. In 2001, i-mode users were expanded for business purpose. Since companies usually use HTML in the Intranet, i-mode became the simplest remote Intranet access tool in the world. Over 50 intranet software adaptations were launched for i-mode in Japan. There is software to convert from Lotus Notes to the i-mode. One can read e-mail through i-mode and check the inventory, price lists, schedules, and even reserve the meeting room. The i-modes development strategy tried to reflect the development of the Internet by basing its standards on that of the Internet. The subsequent development in 2001 was to integrate Java technology and SSL technology, which gives end-to-end security to content providers. With these technologies, users will be able to download applications from the network and install them on the phone. This will allow content providers to provide even more attractive content.
5.3 Telemetry Although telemetry technologies have been used for years to collect values and variables from remote devices, the convergence of wireless, computing, and the Internet have created affordable and practical tools that make it easier to provide end-to-end telemetry solutions. As the penetration of wireless technology increases, economies of scale in manufacturing wireless transceivers will allow them to be installed in a number of machines not previously imagined.
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Many applications can be supported by SMS today, but with the advent of high bandwidth packet data services, the capital expense, service cost, latency, and message size will dramatically improve. Eight core segments may be identified, as shown in Table 5.2. Table 5.2 Telemetry Application Segmentation (1) Segmentation
Application
Benefits
Example
Alarm and security
Commercial/ residential security alarms
Alarm and status messages sent to alarm monitoring center
Smoke detectors Fire alarms
Security against compromise of wireline connections
Burglar breaks into a house and cuts the phone and power wires. Alarm company is notified of break-in and dispatches police.
Pipeline-corrosion systems
Monitoring of environmental conditions
Agricultural, irrigation, and environmental
Water-pump failures, Alarm system for levels and hazardous environmental contamination conditions Air-quality systems
Asset management and tracking
Office equipment, industrial machinery, and manufacturing processes Vending machines
Monitoring of meter information Service diagnosis and maintenance Inventory management Fleet/route management
Atmosphere controls
Heating, ventilation, and air conditioning Refrigeration, temperature, and humidity controls
Health care
Health status monitoring devices
Air-quality standards Temperature controls for food and other perishable items Climate control for greenhouses and agricultural products Patient health-status alarms
A city registers unusually high air pollution readings. Public service announcement is sent out warning those with medical conditions to stay indoors. A delivery truck follows a specific route to fill Coke vending machines. Truck can be rerouted if the vending machine is still full from last delivery. A commercial refrigerator door in a restaurant is left open after a food delivery. An alarm is triggered, alerting people to close the door to save the food from spoiling.
A patient takes a blood test every day. Test data Mobile patient monitoring is sent to hospital where doctor can monitor patient Centralized storage of daily. patient
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Segmentation
Application
Benefits
Example
Public and municipal services
Parking meters
Parking-meter servicing
Highway tolls
Service-route management
A city is losing money every day because parking meters are full or robbed. Meter attendants are rerouted to full meters, and police are dispatched to vandalized meters.
Transportation systems and facilities
Streetlights Railroad crossing switches
Preventive security for hazardous public situations
Vehicle location
Inventory management
Vehicle engine computers
Emergency communications
Container asset
Remote vehicle control
Tracking
Vehicle maintenance
Utility meter reading
Reduced cost of servicing meters
Navigation services Utilities
Oil and gas pipeline facilities
Customer account management Remote meter control
A truck is making an urgent delivery but there is a major accident that delays arrival. Information can be sent to driver to take alternative route to deliver shipment on time. A customer is moving out of town. Utility company can provide up-to-the-minute billing to settle the account.
Enhanced services
5.3.1
Vehicle-Related Mobile Computing
This application consists of three elementary components: smart car, smart truck, and smart cargo. The three complement each other and establish a future intelligent transportation business. 5.3.1.1 Smart Car and Smart Truck
The worldwide car market continues to grow. In 2001 there were 750 million cars, taking Western Europe into a leading position with 200 million cars and 18 million trucks. No wonder that computing in and around the vehicle is of increasing importance. BMW introduced in 2001 a Palm-based smart car solution with remote control functions and in-car features replacing the car key. Internet access, and route navigation, car telephone, MP3 player, airconditioning, board computer, route recording are some of TX5s product features. Voice recognition is one of the future items in this development.
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An intelligent agent or smart card in mobile phones or PDAs establishes interaction and control of the vehicle and vehicle services. The vehicle can provide the following services to the mobile phone: • Location of the car; • Remote car access; • An enhanced user interface; • Information and records to the mobile phone or device; • User identification by mobile device; • Interaction and remote control from the mobile device (e.g., open
car when user arrives, lock car when user leaves); • Interaction with other cars (ad hoc networking). 5.3.1.2 Smart Cargo
Smart cargo comprises smart cargo containers and smart packages. Both have some computation capabilities, local memory, and mobile wireless communication. The obvious advantagesavailability and security of informationimprove and streamline the whole transportation system. A container-embedded computer that knows the containers attributes is able to communicate to allow automatic container processing and handling. Container attributes include knowledge about origin and destination, routing, location, bill of lading, destination, handling instructions, and shipping requirements. The cargo packages are equipped with smart tags that allow automatic localization of packages inside the container. The smart tags are a means of automatic identification of packages and access to packagespecific information. As such, they also allow automatic package routing, processing, and loading, to tighten up and improve shipping, distribution, logistics, loading, and processing. The basis of a comprehensive and highly automated system is a mobile wireless real-time information network. Also required is smart and automatic cargo processingrouting and loading equipment that interacts with both the smart cargo and routing applications. Smart carriers and smart loading equipment also provide the link from smart cargo to central operations, exchanging information about load, destinations, and transport requirements. When a carrier arrives at the yard, the yards system is automatically informed about the incoming load (e.g., by a WLAN). Automatic loading equipment, already prepared because of advanced planning by the real-time
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information network, quickly strips the carrier and container, and reconsolidates the cargo accordingly. 5.3.2
Health Care
The hospital, with its large staff, large size, and intense need for critical information, represents a spectrum of wireless mobile application possibilities for increased efficiency and improved patient care. Wireless mobile computing enables health care organizations to quickly move patients through the care process, speed reimbursements, minimize mistakes, and optimize staff utilization while delivering appropriate outcomes and exceptional patient satisfaction. In the hospital, WLANs can be used to support both clinical and nonclinical applications. Not only can a nurse, therapist, or technician have fast access to patient information, but the same WLAN backbone supports applications, such as inventory and supplies management, durable medical equipment, and other asset tracking and file management. This means that with an array of supported wireless devices already available, WLANs not only extend the reach of the network, but preserve the value of that investment. 5.3.2.1 Wireless Hospital
An integrated WLAN system in combination with mobile computing devices can support hospitalwide clinical and nonclinical patient-centered service applications to allow hospitals to run more efficiently, effectively, and competitively. As an extension of existing enterprise-wide information systems, the WLAN-based mobile computing technology increases the reach of current IT investment and infrastructure, bringing computing to the point of activity. Users can move freely in the hospital without the constraints usually associated with a wired network. Personnel can move from room to room untethered, without having to return to a fixed station to input or check information. Hospital staff has real-time access to information. Caregivers can leverage information at the bedside or point-of-care to both make decisions and take actions with greater accuracy and efficiency. The system enables care providers to immediately perform clinical documentation and access patient information, clinical protocols, or drug references at the point of activity. This system improves the quality and reduces the cost of patient care, as well as increases automation. And because wireless networks can be
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operational significantly faster than a wired network, they allow unprecedented flexibility and responsiveness to organizational needs and changes. Smart Badge Application
A smart badge can be one of the mentioned mobile computing devices. It is smart, context-aware, serves different users, and provides user-dependent access to the wireless hospital system. All users in the hospital (doctors, nurses, orderlies, technicians, administrators, and even guests, visitors, and patients) would wear a smart badge that knows what is going on around the user (provided by the mobile computing system). In that setting, the wireless hospital would recognize a doctor when he/she entered the patients room and relevant charts would automatically pop up on the computer screen. If someone approached the screen who was not authorized to see the patient information, it would go blank. The smart badge would know when the doctor put it down and, if someone else picked it up, it would have a whole different set of e-services personalized for that person. One similar device, BadgePAD, is already in development at HP Labs [11]. Smart Tag Implants for At-Risk Patients
Described as the Digital Angel, such a smart tag is an in-human-implantable device. It will be used for emergency location and medical monitoring of at-risk patients. This is good for patients who stay at home, as well as for those patients in the hospital, when certain biological functions have to be monitored that cannot be measured from outside. 5.3.2.2 Medicine Cabinet
A smart medicine cabinet monitors and controls drug consumption in hospitals and retirement homes. Smart medicine cabinets identify tagged drugs and measure their consumption (e.g., by measuring their weight). By identifying users (and user-dependent access to drugs), it can track the use of medicine relative to users or patients. Example Applications Clinical Documentation Patient information is entered at the point of activity; range checking on data entry for intake or output measurements takes place directly at the bedside. The wireless hospital can immediately alert the care provider to gather additional information or to confirm or reevaluate the information they collected if it is out of range. This can save time,
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eliminate significant documentation errors, and, most importantly, improve patient care. This is also significant for defense of legal action. With wireless networks and real-time chart access and updates, physicians can provide documentation to malpractice insurance companies that there have been checks for drug interactions or verification that certain criteria were evaluated under high-risk medical conditions. Clinical Care The mobile computing system allows care providers to have access to the hospital information system immediately, along with access to other resources including drug references, real-time automatic adverse drug event monitoring, the latest laboratory test results, current care plan, and clinical protocols. For example, drug interactions can be checked against the patients medical record at bedside prior to giving the medication. Although such errors can be stopped at the pharmacy, the high cost of an adverse event means that checking at the point of care is an excellent safeguard. Mobile Professionals Respiratory caregivers, physical therapists, and other mobile professionals profit from the wireless hospital by having immediate access to orders and the most current patient information. They can manage their time more efficiently, while improving their delivery of quality patient services, whether in a departmental setting, intensive care unit, or other specialty care floor. Bedside Admitting, Discharge, and Transfer Admitting and assessment information is taken at bedside. The patient is more comfortable, and information is instantly available to all clinical departments. As the patient moves through the care process, his or her change in status and location are immediately documented. Requests for transfers are accomplished instantly, eliminating potential patient coordination mistakes because all clinical departments have access to a patients status and whereabouts in real-time. At the end of the hospital stay, patients may be discharged directly from their room, eliminating the need to make another stop prior to leaving the hospital and increasing convenience for patients that are not ambulatory. Medication Administration and Bedside-Drug Use Evaluation The wireless hospital helps to ensure that a licensed care provider gives the right medication to the right patient, at the right time, in the right dosage and strength. The wireless hospital, the smart medicine cabinet, the smart badge, and RFIDtagged drugs with automated unit dosing all work together to make the following scenario real. Prior to administering medication, the drug, the
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patient, and the care provider are automatically identified. The patients medication profile is immediately checked over a WLAN to ensure that the medication has been approved for administration. It simultaneously checks for any adverse drug events. Detailed documentation of the medication administration event has automatically taken place. The smart badge in the wireless hospital further allows the nurse or pharmacist to be directly connected to the pharmacy system from a patients room to make therapeutic substitutions, changes in dosage, or check interactions on-line. Potential drug interactions or contraindications can be managed instantly. Also, medications are released more quickly from the pharmacy. 5.3.3
Other Applications
Status and control of facilities, homes, and equipment in various environments will be based on intelligent appliances in the future; as a result, more networked solutions will be required. The complexity of the solutions, however, will delay the development of this potential market.
5.4 Mobile E-Commerce With the power of e-commerce and the advances in wireless technologies, mobile commerce (m-commerce) is rapidly approaching the business forefront. With the increasing bit rates in wide area mobile networks, along with the convergence of the Internet with wireless access, the integration of voice, data, audio, and video will allow e-commerce for the user being mobile. M-commerce builds on mobile wireless devices and a ubiquitous information infrastructure. As such, the technologies and their roles described in the previous chapter (smart cards and 3G mobile phones) are enablers and the keys to a mass-market boom of mobile e-commerce. The limiting factors for mass-market acceptance of both e-commerce and mobile e-commerce are security and compatibility. Smart cards offer the required security and they will become interoperable around the world as they are built on generic standards. 3G mobile phones will provide the interface for mobile e-commerce to access the networks and to use network services. M-commerce is about two things: 1. E-commerce over mobile wireless devices rather than fixed devices; 2. The commercial exploitation of the mobile Web and its contentit is not just about stand-alone secure transactions through
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mobile phones, but it is also about synchronization, interoperability, and using appropriate technologies and content. The business volume of m-commerce is quite promising. Figure 5.8 shows revenue forecasts for m-commerce in the Western European and worldwide market. M-Commerce Applications
M-commerce applications may be categorized into three main categories: transaction management, digital content delivery, and telemetry services. Table 5.3 gives examples of active and passive m-commerce applications assigned to the six service categories in 3G markets, as well as some relevant characteristics. Transaction Management The mobile user initiates a wide range of business transactions from a mobile wireless device. On-line shopping sites tailored to mobile phones and PDAsincluding browsing, purchase, payment, and deliveryhave already shown in various environments. These Web sites include all the necessary shopping features, such as seen today in Japan with the i-mode service.
250 Operator revenues for Internet and Intranet access Infotainment, MMS, location-based services: Business Consumer
US $ (billions)
200
150
100
50
0
2001
2002
2003
2004
2005
2006 Year
2007
Figure 5.8 Forecast for m-commerce. (Source: UMTS Forum.)
2008
2009
2010
Applications
331
Table 5.3 Relevant Items of M-Commerce Related to 3G Service Categories Mobile Internet Access
Mobile Intranet Access
Customized Infotainment
Multimedia Messaging
LocationBased
Rich Voice
Always-on: e-mail, Web, instant messaging
Security: Mobile VPN
Security: end-to-end
Person-toperson
Navigation Yellow Pages Guided tours Local weather Local traffic
Person-toperson Speech Videophone Telemedicine
Bit rate: HTML allowance
Bit rate: HTML allowance
Payment: M-wallet, micropayment
Machine-tomachine
Personal trading
Tele-education
Information Virtual market Access M-ordering M-shopping M-banking M-advertising
Field sales Order automation
M-banking M-trading M-ticketing M-shopping M-gambling M-advertising M-news, Info Mobility: global
Video Graphic Photo Audio Animation Text
Instant coupons
Business user Consumer
Business user Consumer
Business user Business user Consumer Consumer
Business user Consumer
Another class of m-commerce transactions involves using a mobile wireless device to initiate and pay for purchases and services in real time (handheld shopping). These kinds of transactions will likely increase as users will save time and handheld shopping will become comfortable and familiar. Finally, m-commerce will occur in micro-transactions. When individuals reach for their e-cash-equipped mobile phones or PDAs (instead of coins) to settle transactions like subway fees, widespread use of digital cash will be a reality. Content Delivery Services Digital content delivery uses the wireless channels distribution characteristics. These m-commerce activities include information browsinginstant retrieval of status information (weather, transit schedules, sports scores, ticket availability, and market prices)and directory services. The CNN wireless news subscription service represents emerging content delivery services.
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Another example is MP3 music download, which is likely to become even more commonplace with 3G/UMTS. Furthermore, transferring software, high-resolution images, and full-motion advertising messages will also become common activities. The emergence of high-quality display screens and greater bandwidth will trigger the development of innovative AV applications. Individuals can use wireless mobile devices to access, retrieve, store, and display videos for entertainment, product demonstration, and distance learning. The transmission and receipt of status, sensing, and measurement information forms the basis for a wide range of new applications involving wireless mobile devices. Innovations in this area let people use wireless mobile phones and appliances to communicate with various equipment in their homes, offices, or in the field. Airlines are testing technology that will let them alert passengers, especially frequent fliers, to seat upgrades, schedule changes, and so on, through wireless devices. Some airlines already have prototype telemetry systems that transmit this kind of information to passengers as soon as they enter the airport or pass near a kiosk-like device. Collecting Measurement Data
Another form of m-commerce is mobile advertising. Stores will be able to market their products and services by transmitting promotional coupons and messages to passers: (e.g., Get half off, if you make your purchase within the next 30 minutes). This type of marketing may give rise to a new challenge: managing m-junk messages without turning off your wireless device. Electronic commerce is very often viewed as electronic business via the Internet. Its structuring into the B2B, B2C, and B2E sectors can be used as a tool to identify the strengths of fixed Internet, the mobile Internet, as well as mobile access to intranets. Table 5.4 shows that B2B is mainly related to the fixed Internet and intranets, whereas B2C, consumer to consumer (C2C), and B2E are oriented towards mobile use. A variety of m-commerce services already exist today on mobile terminals that use SMS type messages in their transaction process or Web-based communications with WAP or i-mode. For example, a mobile user (a customer) has sent a message to a service address representing the retailer, and the retailer sends a message to the certification agency to get the approval. The retailer can then confirm placement of the order via SMS to the customer. Similarly, this works with smart cards (banking card, SIM card) with a PIN. Marketing and Advertising Services
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Table 5.4 Electronic Commerce Business Sectors E-Commerce and M-Commerce B2B
B2C (C2C)
B2E
Network infrastructure
Fixed Internet, intranet
Mobile Internet
Mobile access to Internet
Characteristics
Web/HTML XML cXML e-mail, FTP
Web/WML cHTML xHTML HTML
Web/WML xHTML HTML
User device
Desktop
Notebook, PDA
Notebook, PDA, handheld
Applications
Transactions, finance, industry
SMS, i-mode, WAP, Extranet/sales, 3G-infotainment, order, location services teleworking
The following mobile applications belong to conventional e-commerce accessed through mobile wireless devices: • On-line payments: Pointing the phone at the set-top box allows one
to purchase what is on the screen (e.g., handheld shopping; reload capability cards; e-purse and credit or debit payments);
• Mobile banking and financial services: The functionality of an ATM
is accessible through the mobile phone (i.e., query a bank account for recent transactions or balance, perform transactions; mobile ATM e-purse reload as well);
• Mobile electronic ticketing: Reserve, buy, and change tickets via
mobile phone while on the move (in the taxi, bus); store reservation code on mobile device or on smart card and pick up at place of departure (airport, metro) or simply use the smart card or mobile device as the entry-ticket.
References [1]
U.S. Army Tank-Automotive and Armaments Command (TACOM), Dual Use Application Program, http://www.tacom.army.mil/acqcen/baa/duap.htm, December 1999.
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[2] Sun Microsystems and IBM, The Network Vehicle, http://www.javasoft.com/features/ 1997/nov/javacar.html and http://www.alphaworks.ibm.com/networkvehicle, August 1999. [3] UMTS Forum, UMTS Forum Report, No. 11, Enabling UMTS/Third Generation Services and Applications, 1012 Russel Square, London WC1B5EE, United Kingdom, UMTS Forum, October 2000, pp. 1822. [4] UMTS Forum, UMTS Forum Report, No. 9, 13, The UMTS Third Generation MarketStructuring the Service Revenue Opportunities, Parts I, II, 1012 Russel Square, London WC1B5EE, United Kingdom, UMTS Forum, October 2001 and April 2001. [5] Locus Location Technology, http://www.locus.ne.jp. [6] UMTS Forum, UMTS Forum Report, No. 15, Key Components for 3G Devices, 1012 Russel Square, London WC1B5EE, United Kingdom, UMTS Forum, December 2001. [7] Dundee Security Corporation Investment Research, Global Wireless Industry Report Parts 1, 2, December 2000. [8] GPS-US Government, http://www.igeb.gov/sa/whfactsheet.txt. [9] Nakamura, H., I-mode and FOMA Examined: Current Trends and Future Development, Presentation, May 23, 2001, Nice, France, http://www.iir-3G2001.com. [10] NTT DoCoMo, To Sell FOMA TERMINALS, http://www.nttdocomo.com/news/ contents/01/whatnew0925.html, September 25, 2001. [11] Hewlett-Packard Labs Worldwide, http://www.hpl.hp.com.
6 Resource Issues UC needs natural resources. We believe that everybody agrees with this statement. Natural resources are raw material for technology production; financial and human resources are needed for infrastructure deployments; and frequency spectrum is the resource for mobile connectivity and global roaming. There is also, however, an artificial resource that becomes relevant: the addressing of devices, persons, and machines. Even network entities require addresses. This chapter discusses the following relevant resource issues for UC: address capacity and frequency spectrum; where they are needed; and the types of resources are relevant for mobile computing in a 3G environment.
6.1 Addressing Capacity in Networked Environments In networked environments, everyone needs a unique address by which an individual is contactable via any form of communicationdata, voice, video, graphics, or textis needed. It is possible, however, that many people will have more than one unique address. In order to protect their privacy, which will become increasingly more important as technology enables tracking of individuals, some people will adopt separate addresses for different parts of their lives, even to enable them to take on different personalities. The device or system in the network will become an extension of the individual, controlling as well as enabling communication.
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6.1.1
UMTS and Mobile Computing
Address Schemes
One prerequisite for UC in a networked environment is a unique address. Universal connectivity under roaming conditions requires mobile address capacity. Names and addresses, like frequency spectrum and land, have the same quality: They are limited. If we consider the telecommunications and the Internet world, we recognize separate addressing schemes, which are related to certain domains. They are described as follows: • In the traditional telecommunications networks, including mobile
networks, we find the ITU E.164 name and numbering scheme.
• In WLANs and PANs, we find the ISO addressing standard and IP
addressing where IP protocols are used.
• In the Internet and intranet world we find the DNS from the
Internet Assigned Numbers Authority (IANA), now managed by Internet Corporation for Assigned Names and Numbers (ICANN). The DNS has an underlying physical addressing scheme, which is in accordance with the protocol standard IPv4 and IPv6.
• It is not yet clear how ad hoc networks will be organized and by
what addressing scheme. It could be either derived from the existing ones (e.g., related to subnetworks based on ISO or IPv6) or something new, tailored to the situation.
Figure 6.1 indicates the address domains scenarios in which a user, a computer, or a device has to be addressed. The addressing schemes have different histories and are therefore only partly harmonized. 15
• ITU addressing (E.164): Maximum of 15 digits allowing 10
addresses worldwide are structured into different schemes: For global services, three digits are used to address the service (e.g., emergency calls in Europe are 112). In December 2001, the ITU allocated the code +878 to the VISIONng Association, thereby offering its members a unique universal personal telecommunications number (UPTN). This number will allow global number portability, regardless of geography or carrier. A 12-digit global subscriber number is chosen by the subscriber. For countries, a country code with 3 digits is used and a 12-digit code is used for the subscriber number. There are individual numbering plans per country, where
Resource Issues
IPv6
WANs WANs
Internet Internet IPv4 Intranet Intranet IPv4
ITU / E. 164 ITU/E.
Active network Network Active PANs PANs
337
UMTS UMTS E.164 E.164// ++ DNS, DNS, IPv4,IPv6 IPv6 IPv4,
ISO 3166 ISO 3166
ICANN / DNS ICANN/DNS IETFIETF
WLANs WLANs ISO 3166
Figure 6.1 Address domain scenarios.
one additional digit is used as a service identifier. Thus, there are 1012 addresses possible per country. • IP addressing: This comprises two address layers: the DNS as the first layer, which is independent from the second layer, the physical addressingwith the IPv4/v6 addressing scheme. The introduction of the DNS for IP-addressing is a prerequisite. On the DNS side, the capacity of the system depends on the number of domains (global or country)75% to 80% are global domain names (gTLDs) and the remaining 20% to 25% belong to country domains (ccTLDs). The domain names are mapped down to the physical address layer, which can either be IPv4- or IPv6-based. IPv4 has a 4-byte (32 bit) addressing capacity. Its limits are theoretically on 4294967.296 addresses; however, because of its structured use (network codes, user host codes), its limits are further down. Initially, IPv4 was planned to uniquely identify 4 billion nodes; however, the rapid increase in demand coupled with the inflexibility of assigning addresses in strict classes led to problems. The introduction of the classless interdomain routing overcame these restrictionsthere is unanimous concern, however, that the capacity of IPv4 will be exhausted in the foreseeable future. The realistic maximum of IPv4 is probably some 200 million hosts. A linear forecast would therefore show an exhaustion of the 200 million IPv4 addresses by 2003. IPv6 has 16-byte (128 bit) addressing and a far higher capacity (3.4 × 1038 addresses are theoretically possible). It
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also provides two address levels for mobility handling: a permanent and care-of address. • ISO 3166: This addressing scheme is structured in the same way as
the ITU E.164 scheme into country codes.
IPv6 was mainly developed to restore the ability to provide a globally unique address for every device (user) on the Internet and to permit the increasingly hierarchical addressing necessary as the Internet grows. Many estimations indicate that the Internet will run out of addresses between 2004 and 2006. The global unique address is a must if devices and persons are mobile. End-to-end security mechanisms work safely only under this condition. Addressing Content
The universality of the Webs Hypertext Transfer Protocol lies in the objectoriented protocol using the URL, which identifies the Internet network resource (object) that provides the expected information (Web site). Thus, URL does not necessarily address the server. HTTP can also directly communicate with SMTP, FTP, Gopher, and others. In these cases, IP addresses are needed. Domain Names
The DNS is a must when using IPv4/IPv6. It exists for IPv4 and needs to be built for IPv6. The IPv6 DNS software was made available in 2001 with the introduction of the root server. DNS servers are vital to every Internet interaction. The DNS performs the vital name and address transformation service that enables applications (e.g., Internet Explorer, Netscape, and Hotjava) to function. Every time a person enters a domain name into a browser and hits enter, a DNS database query is launched via the root server or the related DNS server, which then finds the appropriate IP address associated with the name. That address is then used to find the desired content in the public Internet or other content locations. Domain-Name Demand
Demand for Internet domain names is large and growing. The ICANN decision in 2000 for new top-level domains could further accelerate the growth in domain names.
Resource Issues
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Addressing in WLANs
WLAN addressing depends on the allocation of WLAN users to the backbone network. This can either be a corporate network (intranet), the Internet, or a WAN. Address capacity, therefore, is considered as part of the overall network domain. Addressing in Ad Hoc Networks
Ad hoc networks are without infrastructure, where multihop wireless communications allow voice and data communications between the users devices. The whole network operates in license-exempt frequency bands. The devices act as nodes and as terminals (so-called terminodes). As it is a selforganized network, each device needs a temporary location-dependent address, which could be a triplet of geographic coordinates (longitude, latitude, elevation). Such self-organized networks need an IP address for each device, which means that certain address space should be reserved within the IPv6 address space. 6.1.2
Estimations of Address Capacity
UC with universal connectivity requires address space in all networks, which are foreseen as the infrastructure for communications. Each communicating device or server requires a physical address. Even in the case of ad hoc networks, such requirements need to be fulfilled. Additionally, addressing is related to the services that will be used and that are provided by certain infrastructures using their address scheme. Furthermore, the user should be allowed to have different identities for different environments (e.g., a personal domestic number and a different business number). At home, the different occupants may have separate numbers, although these may be associated together. Thus, a caller might call indicating the desired individual at that house but also allowing another to respond to the call if the first is not available. This might be achieved by a mixture of multiple subscriber profiles and subaddresses (as is the case today) or by a new mechanism. This leads to several layers of addressing. For example, voice services are generally provided by ISDN, PSTN, and PLMN using the E.164 addressing scheme. Thus, a user, who is addressed within UMTS for a voice service, needs an E.164 address. In case of addressing a UMTS user for sending him an e-mail, the DNS has to be used. Combined use of different address schemes is necessary when using an ITU-access network to get to an Internet host or vice versa. UMTS is integrating Internet services into a mobile environment. This results in the management of different addressing schemes E.164 and
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IPv4/v6. In order to enable the addressing of a voice user (E.164 address) from an Internet-based user, the IETF Working Group ENUM is working on an extended numbering system with generic address translation, where the E.164 number is reversed and linked with a gTLD called .arpa. For example, E.164 number: 0049 89 123456; related ENUM domain name: 6.5.4.3.2.1.9.8.9.4.e164.arpa. The transition from a 3G network UMTS to an ad hoc network (PAN) is not defined. Figure 6.2 shows UMTS services and their relations to addressing schemes. Increasing mobility will also impact the DNS of the Internet. In the fixed Internet situation, the name service maps a given name to its physical address, which is location dependent. When a mobile is involved, the mapping has to find the current address of the resource. Thus, a globally unique name regardless of the location will become essential. The upcoming bottlenecks on the naming level are under discussion within ICANN and IETF. Within ICANN the discussion is to allow more TLDs (gTLD and ccTLD); the IETF discussion centers around adding uniform resource names (URNs) to the existing URL in the Internet. URNs will be globally unique and provide resource naming regardless of location. They will also be persistent and scalable (in the context of the resource life span), transcribable, and readable by humans. Based on the current IPv4 address numbering system, IP addresses are widely considered to be in short supply. This shortage can be mitigated by PSTN, ISDN, cellular
Services
Telephony
Data
Fax
Internet/Intranet/LAN
SMS
SIP
SMTP
FTP
HTTP
CHAT
Name value Name type
E.164
ITU, 3GPP
User@domain IETF, ISO, ICANN*
Name entity
Person/ terminal
*ICANN = Internet Corporation for Assigned Names and Numbers
Figure 6.2 UMTS servicesuse of address space.
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341
changes in IPv4, such as classless interdomain routing (CIDR) (which allows more efficient assignment of IP address blocks) and network address translation (NAT) (which allows the use of a smaller number of addresses). Similarly, the dynamic host configuration protocol (DHCP) has also had some impact on the sharing of IP addresses. Even with these techniques, demand for IP addresses will exceed the available IPv4 reserve between 2004 and 2008 depending on country and address consumption on private networks in the United States. Because of its early Internet growth, the United States has the majority of IPv4 addresses from the common world pool of addresses. Therefore, Europe and other regions are expected to run out of IPv4 addresses sooner. This has resulted in the early adoption of IPv6 trial projects by some European operators, universities, and the European Commission. New telecommunication services and capabilitiesboth wireline broadband access and mobile broadband access that will provide high-speed, always-on data accessdrive much of this growth. Mobile data services will grow with the introduction of IP-based 3G networks starting in Europe and Japan in 2001. Service providers, such as mobile operators and ISPs are large consumers of DNS servers and IP addresses. This is because these types of companies have subscribers that require access to IP addresses each time they want to access content through the Internet. As it is assumed, the Internet will exceed the address capacity of IPv4 by 2004 to 2008. Estimations are desirable upon the demand of addresses considering UC. The following forecasts have to be taken into account: • Forecast of PCs and servers on the Internet; • Forecast of the mobile devices; • Forecast of mobile network-related servers; • Number of services per user, which need to be addressed indi-
vidually;
• Forecast of the number of users in ad hoc networks.
In addition, it is assumed that the mobile device is always on, which means that it needs a permanent IP address. For the estimations in this chapter, forecast figures from different sources and the authors own assumptions were considered. This is shown in Table 6.1. For the fixed Internet, it is
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UMTS and Mobile Computing
assumed that in 2005 the same user to host relation will be used as today (2:1). This means for 400 million business users, there will be approximately 400 million host addresses needed. For 2010, however, a certain portion of users will have a unique address independent from the host. This will be necessary for transient users who will roam between the fixed and mobile Internet (convergence). Based on these assumptions, Table 6.2 presents a global address estimation for UMTS, for mobile users and their devices, and the network nodes for 2005 and 2010 and for ad hoc networks. For the mobile Internet, it is further assumed that for business 100% and for consumers 50% of all mobile users will be always-on and will therefore need one IP address, in addition to a care-of address for roaming. As shown in Figure 6.3, the number of Internet hosts has already surpassed 100 million [1]. The linear forecast would lead to an exhaustion of the 200 million viable IP addresses in 2003. If there is an unexpected need for mobile IP addresses, then the IPv4 address capacity would exhaust the address space before 2003. This is, of course, dependent on the regional situation in the Internet, and on the mobile development there. Table 6.1 Forecasted Figures and Assumptions for Address-Capacity Estimations (World), 2005 and 2010 Infrastructure
Internet business consumer UMTS business consumer
Remarks
Devices per User
a b
2010 2005
2010
2
400
500
1
300
400
2
100
300
1
100
400
1
1
50
400
0.8
2
2
1
1
0.5
Handheld, PDA, notebook, person, machine, car, office, household, pet
4
2
2
Servers, workstations Software
Number of Users (Units) Forecast (Millions)
2005 Desktop, laptop
WLAN, ad hoc Desktop, laptop, PDA, 1 networks notebook Network equipmenta, middleware
Addresses per User
0.5
b
Assumed 400 to 1,000 mobile networks, 2,000 entities per network (nodes, middleware). Address pooling.
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Table 6.2 Estimation of IP-Address-Capacity Demand for UC
Year
World Population (Billions)
IP Address Demand Internet UMTS (Billions) (Billions)
WLAN Ad Infrastructure Total Hoc (Billions) (Billions) (Billions)
2005
6.5
0.55
0.25
0.05
0.001
0.85
2010
7.5
1.4
1.0
0.5
0.002
2.9
Internet hosts (millions)
120 100
Old New
80
Adjusted
60 40 20 0 1991
1992
1993
1994
1995
1996 Year
1997
1998
1999
2000
2001
Figure 6.3 Internet host growth. (Source: [1].)
The following variables for address capacity estimations remain difficult to quantify: • The use of NATs to increase the utilization of IPv4 address space; • WAP proxy server deployment (similar to NATs in terms of saving
IP address space); • The impact of dynamic address assignment in an always-on environment; • The possible impact of end-to-end IPSec. This leads to an increased address-capacity demand for secure end-to-end communication
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UMTS and Mobile Computing
providing a unique address to each user (use of NAT inhibits endto-end IPSec); • New demands from the plug and play (auto configuration) market.
It would appear from the estimations of the UMTS Forum [2], the GSM Association, and NTT DoCoMo that IPv4 address exhaustion is unlikely to occur by 2004 to 2005, although this cannot be guaranteed. From the Internet Software Consortium estimation, it seems more likely that IPv6 might be needed earlier. Global Domain Names
In 2000, ICANN decided that there should be new top-level domain names (TLDs). In addition to .com, .org, .net, and .gov, the ICANN board agreed on .biz, .info, .pro, .name, .aero, .museum, and .coop. These new TLDs open up new naming space for services and for persons (.name). However, if UC takes place in the mass market, new concepts will be required, as machine-to-machine communications do not necessarily need TLDs. In addition, ubiquitous devices belonging to a company or person could be seen as subaddressed entities under a domain name. TLDs for Mobility
By considering the estimated forecasts for mobile Internet/UMTS, it becomes clear that the mobile sector will require additional name spacesnot only more address capacity. It may be assumed that mobile communications demand for names could be in the same order as for the wireline Internet.
6.2 Frequency Spectrum The cost and lack of spectrum availability could be a major barrier to the development of the mobile market. Insufficient spectrum to meet the needs of the marketplace will result in a traffic capacity bottleneck. Under these circumstances, market development will be suppressed. Spectrum Barriers Versus Capacity
There is no way for UC without wireless communications. Wireless connectivity is a limited resource. Unlike the wired world where individual access lines connect user devices, for the wireless world a radio field has to take over
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this role for a large number of users who sometimes roam from one location area to the other. A radio field builds on radio frequencies. The amount of frequency spectrum that is needed depends on technology, application, and traffic capacity. For most of the mobile radio systems, frequency spectrum is an international or global coordination issue. In order to avoid complex, multifrequency band technologies, mobile radio spectrum needs to be harmonized. Mobile systems allow two-way point-to-point connectivity. Thus, traffic capacity, which depends on the number of users and their traffic in a cell area, is the most critical factor. The growing demand of frequency spectrum for wireless applications goes in line with the increasing mobile penetration rates, with the number of applications and their bit rates, especially in data communications. System improvements are continuously under development in order to keep the frequency demand within acceptable limits. Frequency reuse and radio cell size are, of course, of central concern to the cellular system operator. There are many different ways to view and define system capacity. It is not a simple unidimensional measurethere are at least a few different considerations and definitions necessary: • Spectral efficiency per radio system technology expressed in bits per
second (bps/Hz);
• Spectral efficiency geographically on a network levelthe geo-
graphical spectral efficiency dealing with bps/Hz/area is determined by cell size and frequency reuse factor (interference and guard bands must also be taken into account);
• Economic spectrum efficiency dealing with the cost factors included
for building up radio infrastructure;
• Spectral efficiency in relation to traffic characteristics (e.g., taking
into account bursty and asymmetric traffic).
One of the most pervasive and relevant questions in the mobile radio field is whether there will be sufficient spectrum in the futurein 2010 and beyondallowing UC in a wireless environment. This question is especially valid for wide area mobile networks, which are (for economical reasons) usually deployed with radio cell sizes from 100m microcells up to 50-km macrocells. In the local area, cell sizes of less than 50m lower the capacity problem considerably. Thus, higher bit rates per user are feasible in such environments to acceptable frequency spectrum requirements.
346
6.2.1
UMTS and Mobile Computing
How Much Frequency Spectrum Is Needed for 3G Services?
The demand for frequency spectrum depends on a variety of parameters. Demographic data, system technologies, and service bit rates are the main criteria that impact the calculations. Thus, a model has to be defined that can be applied together with an agreed calculation methodology. Experience has shown that methodology can be more or less made common. Market models and databases, however, may differ from country to country [3]. The determination of spectrum utilization depends on three principal inputs: 1. The market, and its segmentation into the different classes of users with their traffic demands (public/private, business/domestic, low mobility/high mobility); 2. The services to be offered over UMTS, and whether these are to be controlled by the network operators or independent third-party providers; 3. The technology to be used, and in particular the flexibility that it will allow optimizing the use of the available spectrum. Traffic Asymmetry
Discussion on the new Internet-related services for the wideband wired access network suggests that asymmetric transmission rates will be the norm rather than the exception. However, in asking the question as to the degree of asymmetry, it seems to grow with the transmission bit rates and the service characteristics. Depending on service scenarios, very different asymmetry factors come into play. For example, in a quasi-instantaneous case, even speech traffic can be highly asymmetric. Furthermore, the discussion on services and asymmetry has revealed that the asymmetry is likely to exist in either direction. With Internet type services, however, the downlink to the mobile terminal will constantly require significantly higher bandwidth than the uplink to the information provider. This may be the case for many applications, but in order to develop a spectrum strategy it is essential to look to the broader picture of the services likely to be developed on the wideband wired local network. Typical of these services are those that seek to use the mobile or wired terminal as a remote information-gathering tool. Remote inspection, emergency handling, journalism, and commercial purchasing are all areas where the remoting (via low-cost manpower) of information gathering allows the
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real-time judgment of valuable specialist expertise back-at-base to be used to best effect. These services generally only require speech and low data rates on the downlink, but have a requirement for high-quality video (with MPEG-4, 384 Kbps) on the uplink. The radio access may therefore need to be flexible in terms of the uplink and downlink bandwidth setup for a call or during a call or a session. The service categories, which were chosen from a market forecast of the UMTS Forum as a basis for spectrum demand estimations, include service with high traffic asymmetries, which can be seen typically for MP3 audio download or future MPEG-4 video clip downloads or streamings. Table 6.3 shows traffic asymmetries as they exist with the Internet today. 6.2.2
3G Traffic Capacity Calculations
There have been and continue to be many worldwide spectrum investigations, and their results are extremely varied. It begins with the numerous methodologies used and the parameter assumptions, which sometimes seem Table 6.3 Traffic Characteristics of Services
Service
Bit Rate
Traffic Asymmetry
Session Time
Data Flow
Voice
716 Kbps
1:1
12 min
Real-time dialog
SMS, e-mail
≤ 64 Kbps
3:1/1:3
0.5 min
Bursty, delay-tolerant
WWW
64 Kbps2 Mbps
7:1
1020 min
Bursty, short delays
Videophone
128384 Kbps
1:1
2.5 min
Continuous traffic flow, real-time dialog
FM music
128 Kbps
50:1
1 hr
Continuous traffic flow
Audio streaming 128 Kbps
10:1
≤ 4 min
Continuous traffic flow, short delays
Remote camera
128384 Kbps
1:20
10 min
Short delays
DVD video streaming
≤ 400600 Kbps
10:1
≤ 1 min
Continuous traffic flow, short delays
TV
≤ 2 Mbps
200:1
30 min
Continuous traffic flow
Document transfer
≤ 128 Kbps
30:1/1:30
Variable
Continuous traffic flow, delay-tolerant
E-commerce E-banking
≤ 384 Kbps ≤ 128 Kbps
5:1 15:1
8 min 5 min
Bursty, short delays
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UMTS and Mobile Computing
to be unrealistic. Therefore, the UMTS Forum, an association of mobile industry operators, manufacturers, and regulators, undertook in 19961998 a comprehensive analysis and created a methodology and database model, which was finally accepted as industry consensus on a worldwide levelthe ITU level. The UMTS Forums work result [3] is applicable to any country by modifying the database used for the calculations on how much spectrum will be needed. This section deals with the question of traffic capacity for a given spectrum and technology. The methodology is derived from the UMTS Forums work. Traffic capacity is considered from two viewpoints: • From services and demographic data; • From spectrum availability and technological performance. Traffic Capacity Demand per Land Area
The first calculation step aims for the required capacity for a given service model and demographic situation including penetration rates. This would actually be the market requirement for a predetermined year. The methodology is shown in Figure 6.4. The market model for the services categories was taken from the UMTS Forum [4]. Table 6.4 gives an overview on the assumed penetration rates of 3G service classes in the city or urban environment for 2005 and 2010. This environment is used since it determines the maximum capacity requirement for a wide area cellular network. Population density values are derived from the number of inhabitants per square kilometer in a certain environment and multiplied by a factor for commuters that are in the area. Paris, for example, has 2.2 million people in an area of 105 km², which leads to 21,000 persons/km². In the central business district, the number could be multiplied by a factor of 2 to 5 (peak busy hour/area), which leads then to approximately 100,000 persons/km². In outer districts (e.g., the suburban and rural areas), far lower population densities on the order of 1 to 3,000 persons/km² are taken into consideration. Furthermore, traffic characteristics have to be considered, as there are circuit- and packet-switched ways of transport in order to avoid unacceptable capacity demand. Also, asymmetric traffic distributions may influence the capacity demand on the uplink and downlink. Overhead for signaling data flow control mechanism has to be added.
Resource Issues Demographic data
Market forecast
Mobile services speech data
349
Mobile penetration subscriptions
Service traffic
User profiles call data
Traffic overhead (QoS)
Traffic parameter/user
Environment: indoor, urban, suburban, rural Population density (Pop/km²)
Traffic Capacity Demand Traffic capacity demand Indoor(Mbps/km²) ( Mbps /km² ) indoor Urban Urban Suburban Suburban Rural Rural
Figure 6.4 Methodology for traffic capacity demand calculations per land area. (Source: UMTS Forum.) Table 6.4 Forecasted 3G Service Classes and Penetration Rates, 2005 and 2010
Service Class
Multimedia
Bit Rate
≤ 2 Mbps
Penetration Rate for City/Urban Area 2005
2010
5%
18%
Data
≤ 384 Kbps
10%
10%
Messaging
64128 Kbps
25%
40%
Voice
16 Kbps
60%
75%
The result of the calculation is the required traffic capacity in megabits per second per square kilometer derived from demographic data and market forecasts. The figures for 2005 and 2010 are shown in Table 6.5.
350
UMTS and Mobile Computing Table 6.5 Traffic-Capacity Demand (City) Based on UMTS Forum Forecasts (1998) Urban (City) Environment
Capacity Demand (Mbps/km²) Voice
2005
Total
24
46
DL1
22
2
22
1
23
Total
44
25
69
DL
39
97
136
UL
39
10
49
Total
78
107
185
UL 2010
Data
Source: UMTS Forum. 1 DL = downlink 2 UL = uplink
Radio System Capacity per Land Area
The capacity of a radio system is mainly determined by the technology that is chosen, the available frequency bandwidth, and the cell size. Spectral efficiency figures lie between 80 Kbps/MHz/cell for interactive real-time services (e.g., voice) and up to 200 Kbps/MHz/cell for delay-tolerant services (e.g., Web, e-mail, MP3 and outdoor MPEG-4, video streaming, and document download). Another factor has to be applied to allow for spectrum partitioning between operators (guard bands). The cell size has the most impact on the calculation result, as the changes have a square law effect on the capacity figures. In addition, the operational mode (either TDD or FDD) impacts the capacity calculation in cases where traffic asymmetry is involved. High or low chip rate TDD can achieve higher capacity in asymmetric traffic situations per radio cell up to 15:1/1:15. The calculation methodology is shown in Figure 6.5. It aims for the traffic capacity that will be offered by the given radio system for a certain amount of spectrum. The methodology is structured into three calculation paths: 1. The radio planning path deals with the expected operation environments (indoor, urban pedestrian, urban vehicular, suburban, rural), with averaged cell sizes for the environments. Only three of the operation environments contribute to the required amount of spectrum, as they coexist in the same
Resource Issues
Radio planning
Environment definition: indoor, urban suburban, rural
Trunking parameters
Define technology/standard
351 Available frequency bandwidth (MHz)
TDD mode spectral efficiency (Kbps/MHz/cell)
FDD mode spectral eff. Kbps/MHz/cell)
Unpaired bands: n MHz
Cell sizes (km²)
Cell sizes (km²)
Carrier bandwidth
Carrier bandwidth
Number of frequency carriers
Number of frequency carriers
TDD system capacity (Mbps/km²)
Paired bands: 2 × m MHz
FDD system capacity (Mbps/km²)
Total system capacity
Figure 6.5 Methodology for radio system-capacity calculations (Mbps/km2).
geographical area. These are in-building (indoor), urban pedestrian, and urban vehicular. The in-building environment coexists, of course, with the suburban environment; however, it is assumed that less population density by a factor of 5 to 10 will appear in the suburban areas. The average cell sizes are derived from experienced figures. They are approximately 80m radius (picocells) for indoor, 600 to 700m for urban pedestrian and vehicular, 2 to 3 km for suburban, and 8 to 10 km for rural areas. They also impact the trunking parameters (Erlang factor). 2. The technology/standard path deals with the characteristics of the radio scheme used. TDMA-based schemes usually go with frequency reuse 3 to 9; CDMA-based schemes with frequency reuse 1. The spectral efficiency also depends on low and high mobility as well as on smart antenna techniques and QoS, including signaling overhead. The result of the calculations is given in Mbps/MHz/ cell. With these figures, taking into account the cell sizes of the operation environment, the traffic capacity on a per carrier basis can be calculated.
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UMTS and Mobile Computing
3. The frequency bandwidth path deals with the amount of carriers or, better, the bandwidth, which the operator receives from the regulatory authority with the frequency license. First of all, the frequency spectrum has to be investigated whether it is for unpaired or for paired use. Unpaired frequency bands are single bands, which are used by the technology for two-way traffic controlled via time slot assignments. For asymmetric traffic, the proportion of the time slots for forward and backward traffic is assigned according to the traffic relations. Paired frequency bands are symmetrical duplex bands separated from each other. Forward and backward traffic can flow at the same time, independently from each other. However, in case of traffic asymmetry, the frequency bands will either be overloaded on one side or underloaded on the other. In addition to these investigations, it is necessary to consider guard bands, which differ depending on the technologies used in the neighboring bands (of other operators). Finally, the netfrequency bandwidth per operator, together with cell size per environment and spectral efficiency, determine the total system capacity for the operator. Traffic capacity may be calculated for different spectral efficiencies and frequency bandwidths. As an example, the following calculations are made: • Spectrum bandwidth: from 2 × 5 MHz to 2 × 60 MHz (paired) +
50 MHz (unpaired); • Spectral efficiency: 180 Kbps/MHz/cell for an average 3G radio system. Table 6.6 shows the calculation results based on the assumptions made. They yield to traffic capacities per operator from 13 to 26 Mbps/km², and from 78 to 110 Mbps/km² for a country. The calculations were based on UMTS Forum assumptions [3, 5]. If the results in Table 6.6 are compared with the traffic capacity requirements in Table 6.5, the following conclusions can be made for the city or urban environment: • The total traffic demand (Table 6.5) of 69 Mbps/km² has an average
downlink to uplink traffic asymmetry of DL:UL = 2:1 in 2005 and approximately 3:1 in 2010.
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353
Table 6.6 3G Radio System Capacity in Relation to Frequency Bandwidth
a b
IMT-2000/UMTS Coreband
Frequency Bandwidth Radio System Capacitya (Mbps/km²) UL + DL = Total (MHz)
Min. per operator
2 × 10
6.5 + 6.5 ~ 13
2 × 10 + 5
6.8 + 9.5 ~ 16.3
2 × 15
9.8 + 9.8 ~ 19.6
Max. per operatorEurope
2 × 15 + 5
10.3 + 12.8 ~ 23
Max. per OperatorJapan; Korea
2 × 20
13 + 13 ~ 26
Max. paired bandITU
2 × 60
39 + 39 ~ 78
Max. bandITU
2 × 60 + 35
41 + 59.5 ~ 100
Max. bandEurope
2 × 60 + 50
42 + 67.5 ~ 110
Spectral efficiency = 180 Kbps/MHz/cell. Urban sector cell size r = 0.3 km Omni.
• Voice and video telephony traffic is symmetric. • The data traffic goes up to high asymmetric traffic on the order of 10:1 (Example from Table 6.5, year 2005: DL:UL = 97:10). 2
• A total traffic demand on the order of 100 Mbps/km can be ful-
filled with the 2 × 60 + 35 MHz frequency bandwidth (Table 6.6), which is available in most of the countries in Europe and Asia. 2 • For 2010, the calculated total traffic demand of 185 Mbps/km (Table 6.5) cannot be fulfilled with the available frequency spectrum. About twice the amount of spectrum will be needed to satisfy this demand. The conclusion is that additional spectrum will be required in 2010 at the latest (see Figure 6.6). 6.2.3
Worldwide 3G Spectrum Identification
Detailed spectrum investigations were done in the UMTS Forums Spectrum Aspects Group [3]. The results represent an industry consensus and are therefore representative recommendations for spectrum planners. They are shown in Figure 6.6 for terrestrial mobile networks in the European
354
UMTS and Mobile Computing 600
Spectrum requirements (MHz)
500 DL
400
388
233
Core band 2 × 60 + 35 MHz
300 DL 200
2G bands 2 × 110 MHz
100 UL 0
163
133
2005 High interactive MM Medium and high MM Switched data Simple messaging Voice
UL
Year
2010
Figure 6.6 Terrestrial spectrum estimates for 2005 and 2010 (EU 15). (Source: UMTS Forum.)
environment including 2G and 3G markets. The future frequency band requirements are on the order of 190 MHz. Similar calculations exist for other parts in the world and for the mobile satellite network markets. Industry consensus on parameters for spectrum calculations in various regions is shown in Figure 6.7. These results are contained in the UMTS Forum Report related to ITU-R [6], which was approved and adopted by Study Group 8 (SG 8). It can be seen that the total mobile spectrum demand differs from region to region. Nearly the same relation exists for the already identified spectrum. The UMTS Forums total estimate is the highest and there is still the belief within the industry that the Forums figures are reasonable. Not shown is asymmetric use of spectrum. The degree of traffic asymmetry is high and will continue to grow with higher bit rates being offered in future.
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MHz 600
582 MHz
Estimated demand 480 MHz Total 2G + 3G
555 MHz
500
∆ = 160 MHz 390 MHz
400 300
Identified 1-2-3 G
Identified 1-2-3 G
200
Identified Identified 2G + 3G 1-2-3 G Identified 1-2-3 G
100
UMTS F
Region 1
Region 2
Region 3
Figure 6.7 ITU-R agreement (March 1999, Fortalezza) on terrestrial spectrum estimates (2010). (Source: UMTS Forum.)
Thus, radio technology has to consider this fact, otherwise higher spectrum demand would occur. The worldwide achievement on the ITU-R level was not on the figures for total spectrum demand, as it was understood; rather that the regions have to reflect their demographic situation and their needs for mobile spectrum. On the basis of this agreement, the regional organization developed their positions on the identification of future extension bands. The European Conference of Postal and Telecommunication Administrations (CEPT), whose task is to develop radio communication policies and coordinate frequencies, represents 44 member states in Europe. It supported the UMTS Forums methodology and views with minor modifications in the database. Priority was given to the band 2,500 to 2,690 MHz as additional spectrum for IMT-2000/UMTS with the band 2,520 to 2,670 MHz specifically for the terrestrial component. In addition, the GSM 900/1800 bands should be secured for migration to IMT-2000/UMTS in the longer term. Arab states and African states in principle supported the position of CEPT. However, the extension band 2,5202,670-MHz allocation seems to be difficult in African states even for later allocations. Region 1
The calculation methodology was supported, but with different parameter assumptionsespecially for data services and user densities in the Region 2
356
UMTS and Mobile Computing
various environments. Thus, the outcome of the spectrum calculations was considerably lower than for the other regions. The Inter-American Telecommunication Commission (CITEL), which belongs to the Organization of American States (OAS) represents the needs and interests of the 34 member states of the region, developed positions mainly supporting the extension band 1,710 to 1,885 MHz. There was no common position because of the difficulties in the harmonization of existing frequency band use. The United States recognized the urgent need of spectrum and also that spectrum discussions are vital for administrations in order to meet their own developmental needs; as a result, the United States supported the consideration of multiple standards in the context of IMT-2000. Region 3 The Asia-Pacific Telecommunity (APT), which was founded in 1979 by intergovernmental agreement to be responsible for regulatory recommendations in telecommunications, represents 30 member states, 4 associate members, and 40 affiliates. APT accepted the methodology and supported the UMTS Forums view with modifications on the parameters in the traffic model resulting in a total spectrum demand of 480 MHz. Also, the 2,5202,670-MHz extension band was supported. The bands from 806 to 960 MHz and 1,710 to 1,885 MHz were considered for later migration to IMT-2000. The World Radio Conference 2000 (WRC-2000)
In May 2000, the World Radio Administrations met to discuss the overall spectrum situation with a main focus on IMT-2000/UMTS. The agenda item 1.6.1 was already created at WRC 97, where the UTMS Forum Spectrum Aspects Group, together with the European Radio Committee (ERC) Task Group 1 (ERC TG1), took the initiative. (The ERC is part of CEPT and is responsible for radiocommunication matters.) Comprehensive regional preparations started long before the actual convention. The UMTS Forums contributions continued with the release of Report No. 7, Candidate Extension Bands for UMTS/IMT-2000, Terrestrial Component [5]. A number of promotional activities took place in cooperation with the ITU, the GSM Association, the GSA, CEPT, and others. In Report No. 7 the UMTS Forum has examined all candidate bands for IMT-2000 proposed by ITU-R TG8/1 in the Draft CPM Report. This review was made from an industry point of view and gave particular attention to the interests of end users worldwide. The final result of the WRC-2000 was a success for the mobile community. As shown in Figure 6.8 [7], it represents a good consensus result seen from an industry point of view for the following reasons:
GSM GSM1800, 1800,PCS PCS
North America
PDC PDC
Cellular Cellular
PDC PDC
PHS
Japan, Korea (w/o PHS)
Cellular Cellular
IMT IMT 2000 2000
PHS MSS IMT2000 2000 IMT
A B
GSM GSM
GSM GSM
UMTS UMTS
PCS
Under discussion D EF
Brazil, Venezuela
IMT IMT 2000 2000
IMT 2000MSS IMT 2000
MSS
Cellular GSM Cellular GSM
MSS
China
UMTS UMTS
DECTUMTS UMTS MSS
MSS
GSM 1800 GSM 1800
IMT 2000 2000 IMT
MSS
GSM GSM
IMT IMT 2000 2000
IMT2000 2000MSS IMT
2,500 2,550 2,600 2,650 2,700
Resource Issues
Europe
MSS
IMT2000 2000 IMT
MSS
IMT 2000 2000 IMT
MSS
1,700 1,750 1,800 1,850 1,900 1,950 2,000 2,050 2,100 2,150 2,200 2,250
1,000
MSS
900 950
C
A B D
C
MSS
ITU allocations
850
DECT
800
Reserve
MSS MSS
EF IMT 2000
357
Figure 6.8 IMT-2000/UMTS frequency spectrum after WRC-2000. (Source: [7].)
IMT 2000
358
UMTS and Mobile Computing
• It is a clear and stable identification of 160 MHz of additional
spectrum, on a global basis, for the terrestrial component of IMT-2000/UMTS. This should be made available by 2010, subject to market demand.
• It identifies certain 2G mobile bands for IMT-2000 to support
future evolution to 3G systems.
• It identifies existing MSS bands < 3 GHz for the IMT-2000 satellite
component.
• It allows access to the IMT-2000 core bands for high-altitude plat-
form stations (HAPS) acting as a platform for base stations of the IMT-2000 terrestrial component.
One important element of the WRC-2000 resolutions was their flexibility, which is described as follows: • The administrations remain free to decide whether they wish to
implement IMT-2000.
• If they do, then the choice of band(s), the amount of spectrum, and
the timing of its availability all remain under the administrations control.
• If not, identification for IMT-2000 does not prevent the bands from
being used for other applications instead.
The WRC-2000 achievements opened up the discussion on the use of 3G services. In this discussion, care needs to be taken especially for the GSM and PCS bands for two reasons: • Worldwide roaming is increasing, thus a harmonized migration of
currently used bands towards UMTS seems obligatory.
• The potential overlap of the PCS plan with the IMT-2000/UMTS
core band the GSM 1800 band leads to compatibility problems.
The United States has started with interim reports (NTIA, FCC from November 15, 2001) following President Clintons memorandum from October 13, 2000, requesting a strategy for 3G telecommunications. The work continues with the goal of granting 3G spectrum licenses by 2004.
Resource Issues 6.2.4
359
What Is the UMTS-Specific Spectrum Demand per Operator in the Initial Phase?
One of the most important issues in UMTS network planning is the amount of frequency spectrum per operator. Of course, this question has to be investigated under the assumption that 2G spectrum will still be in use by 2G, both systems and services. Thus, it is necessary to make a market split between 2G and 3G radio networks in order to come to reasonable calculation results. The UMTS Forum conducted such investigations [6] and concluded that the recommended minimum spectrum per operator is 2 × 15 MHz paired and 5 MHz unpaired frequency spectrum for the first 3 to 5 years of network operation. 6.2.5
Spectrum Demand for WLANs or Ad Hoc Networks
In local area or ad hoc networks, cell sizes are usually small because of the domination of hot spot deployments, indoor applications, limited number of users, frequency range, and restricted transmit power. The data rate requirements and the interference potential in an office environment determine the spectrum requirement. A designation of one frequency band or a few closely spaced frequency bands for all types of IEEE WLANs and HIPERLANs allows flexible sharing of the available spectrum according to local demand. WLAN Coverage and Capacity
In order to achieve extended coverage and capacity, careful planning and testing needs to be done. Service areas in the corporate sector are usually in the order of several tenths of a square meter up to several square kilometers. Large service areas could include a university campus or a large company facility. As the cell size of one WLAN is usually small (≤ 1km²), terrain is not a propagation problem. Rather, the layout and construction of buildings determine the coverage area and impact the planning of an extended services set (ESS). Reduction of cell sizes to less than 30m (through walls and other office partitions) is sometimes necessary. Regarding capacity, the IEEE 802.11 Protocollike Ethernetis contention-based and, therefore, has to be taken into account in addition to the intracell and intercell radio interference including multipath fading. In multicell environments, capacity may be degraded considerably without careful planning and tuning of the radio cells. One of the possibilities is to partition the frequency bands for the adjacent cells (up to three possible in the 2.4-GHz range). Another planning possibility is adjusting the receiver threshold settings to control the size of the
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coverage area. An additional problem in a multicell environment (ESS) is called the hidden terminal problem where a station recognizes a free access to a channel although it is already taken by another station. The following analysis is based on three application scenarios: 1. Office deployment scenario covering applications, such as multimedia conference, asymmetric video, telephone, Internet browsing, teleworking; 2. Industrial deployment scenarios including manufacturing applications and industrial monitoring; 3. Other deployment scenarios (e.g., high-quality AV access and distribution, database services). A summary of the data rate requirements based on the example deployments listed is given in Table 6.7. It contains reasonable assumptions for IEEE 802.11b and shows the total data rate as assumed in each case. Table 6.7 also includes factors for the efficiency of the network protocol (e.g., TCP/IP) and for the protocol efficiency of the air interface that takes into account the signaling traffic generated by the link-level protocol. The maximum spectrum requirement is based on the data rate requirements during the busy hour for a large office area and a frequency reuse factor of 3. The large office environment is considered representative of the upper limit for the radio network planning. The following example illustrates such a scenario: • Total office area: 100 × 120m = 12,000 m²; • Number of users: 1,200 (1 user/10 m²); • Average data rate per user including data overhead: 5 Mbps; • Percentage of simultaneous active users: 15%; Table 6.7 Assumed Data Rate Requirements for WLANs IEEE 802.11b Environment Net Data Rate Overhead Factor Bit Rate with Overhead Office
26 Mbps
Industrial
6 Mbps
Other
2 Mbps
∼2 ∼2 ∼2
∼ 411 ∼11 ∼4
Cell Range ≤ 60m ≤ 300m ≤ 100m
Resource Issues
361
• Total traffic capacity per area: 5 Mbps × 1,200 × 0.15 = 900 Mbps; 1
• Spectral efficiency : 0.5/bps/Hz/cell (includes coding) = 11 Mbps/ • • • • • • •
22 MHz/cell; Channel bandwidth: 2223.5 MHz (total bandwidth including guardband: 26 MHz); Cell radius: 5m; Cell size: 80 m2; Number of access points: 12,000 m2/80 m2 = 150; Number of users per cell: 8; Cell loading: 8 × 5 Mbps × 0.15/11 Mbps = 55%; Frequency reuse factor: 3 (assumed).
The total spectrum requirement is 3 × 26 MHz = 78 MHz. There are other spectrum estimates based on higher bit rates and traffic assumptions (e.g., for future RLANs with up to 54 Mbps). They lead to bandwidth requirements of between 200 and 500 MHz, which may be fulfilled with new frequency allocations in the 5-GHz range. 6.2.6
Worldwide WLAN Spectrum Identification
Many WLANs operate in the unlicensed ISM frequency spectrum at 915 MHz, 2.4 GHz, and 5.7 GHz; the majority of systems operate in the 2.4-GHz ISM band. They are optimized for picocells with very low transmit power in the order of 100 mW down to less than 10 mW. HIPERLAN/2 systems are foreseen to operate in the 5.2-GHz bands, which are under discussion within the CEPT and other frequency administration bodies. Figure 6.9 shows the present worldwide availability of frequency bands for WLANs [8]. The 14 IEEE 802.11 DSSS channels are used particularly in the various countries. In some countries it is possible to use up to three noninterfering bands in the same environment. The minimum bandwidth per IEEE WLAN according to 802.11b is 22 to 23.5 MHz (with guardbands 26 MHz). In Europe 9 channels are available, which allows campus networks with good capacity. 1. According to the specifications, the spectral efficiency is assumed to be 0.5 bps/Hz per WLAN, which is considered as theoretically achievable for different modulation and channel coding schemes of WLANs according to IEEE 802.11b.
362
1
2,399
2,425
7
2,429
2
2,404
2,455
2,430
13
2,459
8
2,434
3
2,409
2,435
5
2,419
2,400
2,410
2,465
10
2,424
2,470
2,445
11
2,449
6
2,430
2,475
2,450
12
2,454
2,420
UMTS and Mobile Computing
9
2,497
2,440 2,444
United States and Canada Most European nations France Spain Japan
14
2,471 2,439
4
2,414
2,485
2,460
2,440
2,450
2,460
Frequency, MHz
Figure 6.9 IEEE 802.11 WLAN band availability in various countries worldwide. (Source: [8].)
2,470
2,480
2,480
2,490
2,500
Resource Issues
363
The Identification of 5-GHz Spectrum for HIPERLANs
In 1999 some regional frequency administrations decided • To designate the frequency bands 5,150 to 5,350 MHz and 5,470 to
5,725 MHz for the use of HIPERLANs; • That the use of HIPERLANs in the band 5,150 to 5,350 MHz shall be restricted to indoor use with a maximum mean equivalent isotropically radiated power (EIRP) of 200 mW; • That the indoor and outdoor use of HIPERLANs in the band 5,470 to 5,725 MHz shall be restricted to a maximum mean EIRP of 1W.
References [1]
Internet Software Consortium, http://www.isc.org.
[2]
UMTS Forum, UMTS Forum Report No. 12, Naming, Addressing and Identification Issues for UMTS, 1012 Russel Square, London WC1B5EE, United Kingdom, UMTS Forum, May 2001.
[3]
UMTS Forum, UMTS Forum Report No. 6, UMTS/IMT-2000 Spectrum, 1012 Russel Square, London WC1B5EE, United Kingdom, UMTS Forum, December 1998.
[4]
UMTS Forum, UMTS Forum Report No. 1, A Regulatory Framework for UMTS, 1012 Russel Square, London WC1B5EE, United Kingdom, UMTS Forum, October 1998.
[5]
Terrestrial Spectrum Requirement for IMT-2000 ITU-R TG8-1/120-E, International Telecommunication Union, Geneva, Switzerland, October 1998; and UMTS Forum, UMTS Forum Report No. 7, Report on Candidate Extension Bands for UMTS/IMT-2000, Terrestrial Component, 1012 Russel Square, London WC1B5EE, United Kingdom, UMTS Forum, March 1999.
[6]
UMTS Forum, UMTS Forum Report No. 5, Minimum Spectrum Demand per Public Terrestrial UMTS Operator in the Initial Phase, 1012 Russel Square, London WC1B5EE, United Kingdom, UMTS Forum, September 1998.
[7]
Huber, J. F., Spectrum Aspects. In GSM and UMTS: The Creation of Global Mobile Communications, pp. 165167, Hillebrand, F. (ed.), London: John Wiley & Sons, Ltd., 2001.
[8]
Hills, A., Bringing Mobile Computing to a University Community of 10000, IEEE Spectrum, June 1999, pp. 4953.
7 Outlook: Telecom + Datacom + Media = Infocom Both the computer and telecommunications technologies are evolving towards challenging scenarios. The convergence of several fieldstelecommunications, datacommunications, and media into infocommunicationsis becoming a reality. New technologies are emerging driving synergies forward hand in hand with the industrys rapid move toward global business and trade. Transport, distribution, and collection of information content are becoming key elements in the business scenarios. Computing is becoming more and more widespread as Internet and intranet users are growing tremendously and traffic is doubling every 6 to 12 months. More than 10 years after Mark Weisers paper introduced UC, it is time to look back and to answer some questions. • How far have we moved along the lines of Weisers vision? • Is technology developing at a fast pace? • Are people becoming more comfortable with the technology?
Actually, some developments happened differently than Mark Weiser expected. Chapters 2 and 3 show the tremendous growth of mobile technologies, which come from digital cellular phones. These technologies are going to be merged with computer technologies, which evolved from the PC. Also, 365
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off-line specific appliances are getting more functionality because they are increasingly microprocessor-driven with small-scale OSs. This is the starting point for mobile computing, which will lead to the second and third phase of mobile computing, as indicated in Chapter 1. These latter phases will deal with ubiquity in a number of environmentsUC as Weiser envisions, however, will come true at a later time. Although processor technologies allow ubiquity to a certain extent today, power supply still limits the migration of computing into many environments. But we are getting closer to IT; a lot of research work is going on in this field. Chapters 3, 4, and 6 show us what technologies and standards are important for UC and what resources are needed. Continued minimization of computing and networking technologies will take us there. The key networking strategy for mobile computing lies in wireless networks with roaming capabilities, which allow users devices to be moved and to interact with different network infrastructures. Harmonization of standards is a must; the air interface is a key element, but not the only one. The more content-related communications becomes important, the more interoperability between worldwide roaming user devices and content provisioning will become important as well. This requires industrywide consensus on selected existing standards for content representation and delivery like markup languages and compression techniques. Figure 7.1 shows the authors vision for the timely development of computing and networking technologies. Mainframe-purpose computers may never go away; however, new areas of computing, which emerged in the last 10 years, will be further developed. Mobile computing brings personalization and privacy as well as the location of the individual into the picture. Relations of individual entities will play a role. Individual and personal profile information and position information need to be added to the device logic and have to be updated while moving from one location to the other. With 3G mobile technologies, such developments have already started and products will be available. However, a market and technology learning curve takes placeuser acceptance of services and applications may be one of the main obstacles to getting to the mass market soon. The addressing of a device, a person, a car, or a pet belonging to a household will certainly be one of the new problems that occur in this evolutionary process. It will be different in hierarchically coordinated IP domains compared to self-coordinated ad hoc domains. The addressing schemes will be more complex in ad hoc networks because each domain registry is independent and normally not visible for the users in other domains. Thus, in case of interconnections between ad hoc domains, address information has to be exchanged that encompasses the location of the user in order to have a unique identification.
Computing appliances Network infrastructures
Mainframe
Peer-to-peer
Client-server
Mobile converged networks Mobile appliances
1 billion
PDA
Mobile ad-hoc networks
Desktop, PC 100 million
10 million Stand Stand Alone alone
Thumb terminal
PAN, HAN MasterSlave slave Remote remote
Workstation, PC
UC
LAN LAN
Mobile WLAN Mobile WLAN networks Networks Fixed Fixed UMTS Networks networks
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Mobile computing devices
Mainframe 1970
1980
2000
2010
2020 367
Figure 7.1 Developments towards UC.
1990
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As globalization continues in the information technology sector, it will revolutionize the industrial structure. The Internetboth fixed and mobilewill drive e-commerce and change the structures and processes in the worlds economy. In many respects, the Internet will evolve similar to the mainframe model: the PC or PDA or handheld with its Web browser is playing a similar role as the thumb terminal in the remote data processing application of a mainframe computer. The servers with their databases are more or less centralized like mainframe computers in the past. Web pages are only a picture of the data, not the underlying data itself. Editing and customizing the data is difficult to do. Also, separate software applications are used for the different computing tasks the user wants to perform (e.g., browsing the Web, writing, editing, e-mail, or instant messaging). A more integrated approach will be needed in the interest of the user, beginning on the human machine interface side. Much of the development, which is coming from the cellular-WAN side, seems to be progressing at a very fast pace. Just 10 years after introducing digital cellular networks, revolutionary steps in radio and core network technology were taken with a strong focus on IP-based services and applications. UMTS changes the radio scheme of GSM from TDMA to CDMA and goes from a carrier bandwidth of 200 kHz to 5 MHz. This is seen by many observers as a precondition for mobile computing towards a mass market. We realize that on the radio planning side it is not only the bit rate, which counts; it is the traffic capacity for a bandwidth of individual bit rates that the market wants to achieve. Mobile computing will require variable bit rates, as there will be many appliances with low to medium performanceperhaps some of them with high bit rate requirements. What bit rates will be needed in the future can only be answered by analyzing the trends in the multimedia service developments and applications. It is the mobile device that mainly determines the maximum bit rate, depending on its processing performance, its signal power, and its battery consumption. There is a whole range of appliances that will be optimized according to service categories, from the very small ones working mainly off-line, up to the PDAs and laptops. The closer we get to UC, the smaller the appliances will be that dominate in various environments. They will require several different bit rates from low to high. The masses of networked appliances will certainly be related to roaming devices, to persons, to vehicles, to industrial equipmenttheir bit rates may dominate in the range of 10 Kbps up to 64 or 200 Kbps. It is interesting to see bit rate reductions due to the development of compression techniques on mobile audio applicationsfor example, MP3 hi-fi quality streaming with high-quality and FM music is feasible with 64 to
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128 Kbps, video streaming with less than 300 Kbps depending on screen size, even DVD quality could be achieved with 384 Kbps. Downloading of audio- and videoclips can further reduce bit rates and delay constraints. Higher bit rate requirements up to 20 Mbps will probably come up in the context of professional applications (e.g., in the business and medical fields). Until 2010, in the wireless mobile sector, we will recognize a steadily growing variety of bit rates. The demand is going upat least on the downlink sideto 2 to 10 Mbps, which is an improvement factor of 200 or 1,000 compared to 2G technologies. This development depends strongly on the process of service innovation that has just begun. In the business sector, the aggregate bit rates will be higherup to 54 Mbps. Thus, short-range wireless radio will offer such bit rates. Because of the short distance, they work at the lowest power levels, with user densities for the most crowded environments. In this sector, ultra wide band (UWB) technologies, 1 to 4 GHz wide, could emerge. UWB occupies frequencies without causing undue interference, because it emits a power just beyond noise level.
7.1 Taking Moores Law into the Future Looking into the semiconductor developments of the last decade, Moores Law profited from the continuously shrinking feature size to increase the number of transistors on a chip and thus increase the speed of the circuits. It should be noted that the memory version of Moores Law is likely to last considerably longer than the speed versionit can get closer to the ultimate physical limits. If we come back to the question concerning limits in the future, we realize that in 10 to 20 years the physical barriers will ultimately include atomic properties that will come with aggressive device shrinkage as well as capacitance cross-talk, soft errors, and other effects. Table 7.1 shows the way into nanotechnology and the molecular atomic level [1, 2]. The limitations of lithographic techniques need to be surpassed. The challenge in lithography is to enable building shorter channel lengths operating at lower voltages. Channel length is understood as the length of the region between a transistors source and drain, which is controlled by the transistors gate. It is typically a factor of 2 smaller than the general lithography dimension. For transistors built between 2008 and 2010, the minimum channel length will be lower than 70 nm [3], yielding a clock frequency of up to 20 GHz. The power supply voltage goes down to less than 1V, which is in line with the power savings aimed for mobile devices. Hetero-bipolar transistors, which combine CMOS-Silizium and Germanium
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UMTS and Mobile Computing Table 7.1 Higher Density Targets of Microelectronics
Year
Feature Size (nm)
Performance/ Transistors per cm2 Clock Rate (million) (GHz)
Voltage (V)
Power (W)
2001
200150
520
0.32
1.22.5
160
2005
12050
4090
36
0.91.5
490
2010
5035
90180
820
0.50.9
5100
technologies, may be available in the medium term and allow processor clock rates of 20 GHz. Researchers at IBM laboratories in corporation with Infineon are designing microscopic circuits that organize themselves into molecular structures under certain conditions [3]. Such molecular technology would be a breakthrough for UC, because these tiny computing elements could be woven into clothing fabrics and use body heat or light for power [4]. Such advances in semiconductor technology will have a major impact on the mobile industry, allowing the use of embedded mobile devices in many environments This may transform the social infrastructure (m-commerce). The increasing value of the Web as the largest vending machine will contribute to this development. The semiconductor development will also allow configurable chips. Logic gates can be changed in any given moment via programming, or reconfigured. Software radio and UWB impulse technology will be feasible with far lower transmission power, minimizing both the mobile devices power consumption as well as human exposure to radiated emissions. The way forward with such techniques appears to be via coexistence with already established radio networks. With such promising semiconductor technology outlooks, the challenge is no longer how to produce a billion-transistor chip, but how to best use hardware that contains such chips and how to organize connectivity and networking. We can certainly envisage that UC will deal in the future with the following: • Low-voltage technology providing large memory size and good
processing powersoftware radio will allow adaptive technologies towards more connectivity;
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• Embedded technology in various environments, which will drive
dynamic situation-dependent services.
7.2 Future Network Architectures It has become obvious over the last few years, that low-cost, small, long-life, and low-powered microprocessor-driven devices will enforce distributed computing. While they contain no disk, no keyboard, nor large display, it is the state of the art to make these devices full-fledged network participants. Networking will provide a way to maintain nearly all customer requirements accessing large pools of information. Plug and play, and unplug means mobile and sporadically detached operation, which is useful and secure. Bandwidth needs will vary and tend to be low to mediumthe network has to be flexible for adaptive clients. The development that began with mainframe computing and that stands today in the client-server position will go forward to more independent peer-to-peer computing that will be characterized by ad hoc networking, mobile agent technology, and distributed databases. Different network architectures were developed in the past decades in the sectors of fixed and mobile network markets. In the traditional sector, the circuit-switched networks evolved to a concentration of traffic towards large nodes; in the Internet sector packet-switched networking led to a decentralized and heterogeneous node-structure with both advantages and disadvantages. The advantages of the circuit-switched networks are guaranteed bit rates and QoS; their disadvantages lie in the bit rate inflexibility and in the growing resource loss with increasing bit rates. The advantages of the Internet lie mainly in the flexibility regarding bit rate adaptations and conversions between servers and terminals; the disadvantages lie in the field of quality of service. All these networks are mainly static in their structure, although their size was dramatically extendedin both the Internet and in the mobile networks. The heterogeneity of the Internet, meanwhile, brought a lot of dynamics into more decentralized networking. In the future, there will be also networks that are organized on an ad hoc basis: these will be spontaneous dynamic networks complementing the further developed existing network infrastructures. The question is, will both work together and how? This question we cannot answer today. Instead, we offer an overview description to indicate what developments will lead into this future networked environment:
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• The traditional way to create service communities is that a central
instance controls the establishment and release of a service community, encompassing the service provisioning, the communications support, and transport of information and the users. An example is the voice service, which consists of network operators, service providers, and the users who subscribe and use the service. This model is extended for mobile Internet services with the client-server approach. It involves more players, such as the ISP, the ASP, and the content provider. Its main functionality resides generally in a central server whose clients will be lightweightcalled thin clients.
• An alternative service community is where users agree spontaneously
to form a service community in a limited area, like people would meet instantly and communicate with each other at a certain location. This ad hoc self-organized network approach does not require the above client-server infrastructure; it is a peer-to-peer dynamic network comprising thick clients. They have more capabilities and use Java, Jini, SOAP, and CORBA for common services, such as lookup and announcement. The roles of the operator, service provider, and user in this scenario are merged into the role of a service community member. Such service communities are independent from an existing traditional network infrastructure but should have the capability to interoperate with centrally organized infrastructures.
In the standardization field, we still see the dominance of the first category of service communities, and some research work is already widening the scope to more comprehensive architectures. Both the Internet and UMTS will evolve with globally harmonized releases and extend their architectures to a more heterogeneous converged system providing increased flexibility in a cooperative environment of WLANs and ad hoc mobile computing. In the research and standardization sector, we already see examples emerging: • Radio access integration: A system that could fit into the vision of
a heterogeneous infrastructure is the European research project Broadband Radio Access for IP-Based Networks (BRAIN). It is a broadband wireless mobile access network and goes beyond current 3G systems and towards the mobile Internet. The project covers three major technical areas: seamless service provision in a mobile environment; an IP-based access network that will support
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picocellular technologies, such as WLANs; and a broadband air interface suitable for hot spots. BRAIN is going to integrate HIPERLAN 2 with UMTS by means of an IP access network. The planned aggregate bit rates are higher than 10 Mbps in a picocell environment by an enhancement of HIPERLAN 2. The IP interface protocols allow connectivity with UMTS; however, handover mechanisms have to be provided between BRAIN and UMTS. • Infostation connectivity: The Berkeley Wireless Research Center at
the University of California at Berkeley and the Wireless Information Network Laboratory at Rutgers University [5] work on a range of systems at the boundary of mobile computing and wireless communicationsthe infostation project. Infostations, like a gas station, provide a source of fuelin this case information. Each infostation contains a radio transceiver that provides low-power, high data rate Internet access to portable devices in a limited area. It will transfer information while the device passes through or by the area. For example, an airport infostation downloads information that could be useful for the flighte-mail, voice mail, reading material. After arrival, another infostation could pick up the information, which was generated during the flight. The cellular-WAN could support the infostation, guiding the user while he moves and updating his database.
• Mobile ad hoc networks: Ad hoc networks were already mentioned in
previous chapters as a new field of emerging technologies. The idea of multihop packet radio networks is not newthe first research work in this area began in the 1970s. The basic idea is to embed the networking functions into a mobile device and to merge the base station function with the terminal function. This leads to the thick client: in this case nodes and terminals are not distinguishablethey are called terminodes [6]. The terminodes are on the move and carry a mobile network, which moves with the terminals. As such a network is autonomous and self-organized, it has to work in license-exempt frequency bands. Such a project is led by the Swiss Federal Institute of Technology in Lausanne, Switzerland. In addition, the IETF has set up a working group devoted to it called mobile ad hoc networks (MANETs) [7]. Also, for UMTS radio techniques, a similar concept was described as part of the system proposals from ETSI (Proposal 1998: Opportunity Driven Multiple Access/ODMA, Vodafone). The size of such networks is not limited
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from a technical point of view; however, practically seen, the scope of applications and services could limit the network. For example, vehicles on the road could create an ad hoc network that is moving. The vehicles need to be addresseda temporary location-dependent address is needed. The location information could come from GPS or terrestrial radio systems (WANs). The ad hoc network cares about traffic security and car-to-car information and services. In addition to the self-organized network, the cellular network could take over the role of an infostation or host-function in case the ad hoc network needs to be supplied with external information: a peer-to-peer communication could take place between both networks. The ad hoc network actually roams from cell to cell and from network to network (see Figure 7.2). Communication between mobile ad hoc networks and UMTS requires unique addresses per terminode. It is of course no question that additional address capacity is needed; therefore, IPv6 protocol sets are a must. The IPv6 Forum will further deal with such requirements in the future [8]. In addition, new addressing concepts will be required using location information.
Converged network mobile and fixed Internet
3G infrastructure macrocell
Pico
Micro
(terrestrial and satellite)
Other telecom infrastructure
Intranets/extranets
Global GlobalRoaming roaming
Ad hoc networks
HANs
Subnetworks Figure 7.2 Vision of wireless mobile and fixed infrastructures.
WLANs
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Convergence
Convergence remains an issue as the final forms of networking and computing remain debatable. The result will probably be composition of static and dynamic ad hoc network structures working together on a peer-to-peer connectivity. Nevertheless, one aspect is clear: The convergence is resulting in increased collaboration between networked environments, whether they are infrastructure, terminals, ad hoc networks, or terminodes. Another question that affects mobile computing in the future is the question of integration of different wireless access technologies into a harmonized mobile environment. The integration of radio zones and technologies remains a project for the future and will not really happen as long as there are no real requirements arising from the market. It was a main target for IMT-2000the result was different solutions from different standardization organizations like IEEE, HIPERLAN Forum, Bluetooth, and the regional standardization bodies like ARIB, ETSI, and ANSI. Meanwhile, it is obvious that the initial vision of a single common radio standard in all environments will not be fulfilled as long as no real demand drives the development in such directions. The upcoming convergence of digital broadcast radio technology with 3G mobile radio also does not look like it will bring a common solution. From a technical point of view, we will have to wait for softwaredefined radio. What appears to be feasible in the short term is on the device sidethe physical integration into a 3G radio and Bluetooth. In contrast to the integration of WLAN-3G technology, this is acceptable for both from a cost point of view. Additionally, it brings two system environments together, which will continue their own evolutionary development. The linkage of the two different system environments is the 3G global mobile many-to-many communications with the Bluetooth desktop interface for downloads and updates in the users domain, using the desktop as the private or business database or infostation. A similar integration of 3G and WLAN would be possible, although it is not visible yet because of many open issues (incompatible WLAN environments, costs). First of all, WLANs still have to reach interoperability status in hardware and software. WLAN integration into a 3G mobile device is even not under discussion yet.
7.3 Devices In the future, even powerful mobile computing appliances will be wearable. Others with low performance will be small enough to fix unobtrusively to any item of clothing (smart clothing), or in some cases even surgically
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implanted. TIMES wear is a new term combining telecommunication, information, multimedia entertainment, and security in high-tech fashion. We could find such wearable electronics, or wearables, in shoes for measuring the walked distance with an integrated microchip, in clothes (SOS emergency jackets), and in glasses. Visual displays will be variedsome providing direct retinal projection of images, others using head-up display technologies on simple spectacles, and quite probably some with the capability to project three-dimensional, holographic images. Thus, virtual meetings will be possible where users can feel as if they are in the same room as their colleagues, moving between them and exchanging information. Interaction with the services or applications will be primarily via voice recognition systems, enhanced by natural language processing and artificial intelligence systems, so enabling the machine (network or computer) to interpret not only the words but the true meaning of a command. The keyboard as we know it today could become a museum piece. Manual interfaces will still be necessary, but handwriting recognition and some form of stylus will be the main tools for input devices. The intelligent pen, which transmits handwritten text via Bluetooth to a PC or smart phone for SMS editing and transmission, has already been introduced. The basis for all these new applications is wireless or sensory connectivity. The problem is the power supply. Many new ideas exist in this field and it may take some time to bring them into reality. The use of wearables will be seen in the near future: in the fields of maintenance and supervision, training, sports, and security services. There already exists an industry consortium called the I-Wear Consortium that discusses smart clothes. Companies like AT&T, Philips, Samsonite, and Siemens are participating. Such visionary developments signalize clearly that there will be no single device type. Users will require a variety of devices that are optimized for the environment in which they operate and the tasks that they need to perform. Experimentation will continue until customers decide on the product forms and functionality they want. Once this happens, the market will settle on a few product forms. There will be a consolidation on the common parts of mobile computing devices, as manufacturers seek to meet customer demand while controlling costs. It is visible today that laptops and Web tablets will be used on the high-end side for providing mobile Web capability. PDAs are becoming talkative and smart phones will be cost-optimized for certain applications. All these devices will use standard markup languages and browsers. Smaller appliances will have limited connectivity. Manufacturers need to develop new devices if they want to remain competitive. They must decide the type of device that they should make.
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Should they continue to make voice-centric handsets, making smart phones the core product offering, or should they develop PDAs or embedded devices? As computers have shrunk from room size to palm size, the manufacturers will also move from stationary to portable and wearable equipment. Wearable computers are always on and their wearers can always use them. Wearable computers will be apparent in every aspect of life: Worn daily, the computer can absorb extremely rich contextual information, including conversation, ambient sound, activities, executed tasks, and location.
7.4 The Smart-Card Issue Smart cards, together with the needed infrastructure supported by policy and legislation, provide the means to protect privacy and confidentiality of human beings. They are important to grant end-to-end security. Smart cards empower people for m-commerce and will be available in many forms: • Multiapplication cards; • Contactless smart cards; • Government cards; • Cards for health care, public identity, identification, authentication,
security, and e-payments.
In order to achieve interoperability and to secure e-business, the e-Europe initiative on e-commerce started to work on smart cards for an EU-wide application. An e-Europe action on smart cards for secure electronic access was launched by the end of 2000 with an agreed technical framework and codes of practice that bring together technology and application platforms. Common specifications shall be the basis for an EU-wide standard. The U.S. government is also keenly interested in the smart-card initiative. Looking into the future, we see a number of manufacturers developing biometric technology capable of uniquely verifying user identity. Fingerprint sensor technology seems to be promising for deployment of mobile devices. It will make the PIN code optional or obsolete depending on the type of transaction.
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7.5 New Services and Applications As the capabilities of cellular terminals broaden, so does the range of potential services and applications that they can support. Matching this potential to the needs of different user groups is one of the major challenges facing the industry. Manufacturers want to increase the price of terminals. The traditional way of doing this was to increase the available features or the performance. Operators want to increase subscriber revenue either by encouraging users to use their terminals more or by encouraging the use of new, valueadded services that will provide incremental revenue. There is little evidence, however, of the detailed expectations of different user groups. The capabilities of networks and terminals will change so radically over the next few years that previous knowledge of user requirements will be of little help in determining what new services and applications will attract users. Operators and vendors face a period of experimentation and uncertainty; guidance is needed in order to avoid tremendous investments into the wrong fields. Market investigations like those of the UMTS Forum in 2001 found wide industry acceptance [9]. Identifying main service categories in order to provide the appropriate network support instead of single applications is probably a better way to go into the future and one that will allow a large variety of creative solutions on the applications level. The following lessons concerning future user requirements for cellular terminals are becoming clear: • Mobile Internet is not the killer application driving the cellular
devices market. It is instead the platform for more device-tailored and person-related content-oriented applications. • Business users will drive the demand for high data rate services. There is good evidence of corporate demand for mobile connectivity to company data and messaging. • There is potential for consumer data services with low to medium data rates, although the direct user evidence is more mixed. • Context-sensitive applications merit further investigations and research work.
Context-sensitive applications will be a field in which the computer is developed to exploit the intimacy between human, computer, and environment. The computer could sense the handshake, trigger its face-recognition system, identify the person, and automatically show the contact information,
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name, and last e-mail the wearer has received. Multimedia is going to create artificial environments that implement rich, interactive, multimodal information spaces. We call this new field situated computing. It will generate a new class of computing applications that bridge the gap between peoples intentions and the actions they can take to achieve those intentions. They will contextually be embedded in real-world situations. These situated computing applications will be able to identify individuals and where they are, what they are doing, what they want, and how they can take advantage of the resources available in their physical environment. They will assist us in our daily lives and make us more effective.
7.6 Mobile Agents Mobile computing in a future UC world will also deal with the creation and use of mobile agentsactive objects than can migrate autonomously from computer to computer on behalf of their owners, users, or programs [10]. Traditionally, distributed applications have relied on the client-server paradigm in which client and server processes communicate either through message passing or remote procedure calls. The mobile agent has three main advantages over the traditional solutions: 1. Processing functions are moved close to where the information is stored. The agent is sent only once and interacts locally without using the network. After having completed its task, it migrates back via the network to its home site with the results. For example, instead of doing a simple keyword-based Web search, the user would send an agent to perform a more intelligent search and filterthe agent would be customized to satisfy the current needs. 2. The mobile agent increases asynchrony between client and server. While its agent executes its tasks, the client does not need to communicate with the server. 3. Agents perform their tasks under real-time conditions without being dependent on a remote procedure call. Agent communication requires a common language to provide secure interoperability and autonomy. Agents must be able to communicate with each other and decide what information to retrieve and what action to take.
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Theoretically, the language should allow heterogeneous agents to communicate. When agents from different vendors parse each others message, they cannot understand each other correctly. The problem stems from differing interpretations. The common language is therefore a key item for standardization.
7.7 Industry Outlook It is expected that, in this decade, information technology will change the key resource in society from machinery to computing and networking, from hardware manufacturing to software production and networking, from capital to knowledge. The skeptics believe that information technology does not belong to the same league of technologies that caused industrial revolutions, such as electricity and the car. They are wrong, however, to dismiss computers and the Internet so lightly. IT has several valuable characteristics. First, it can enhance efficiency in many different parts of a company and in nearly every sector of the economy. Electricity increased productivity largely in manufacturing of goods like cars, and oil did the same for transportation. Software production, however, does not need such kind of production. Information technology can also enhance the efficiency of services. Many services are increasingly mobilespeed is one of the main quality criteria. At last, by reducing the cost of information and communication, information technology helps to globalize markets for products and for capital. In exchange, globalization spurs competition and speeds up the diffusion of technology through foreign trade. These are the main reasons why IT is needed as help to raise productivity, and productivity is one of the most critical elements influencing the living standards for countries and the competitive position of companies. Networking, partnering, and associating are the key words of the digital economy in the twenty-first century. Many industries will converge on networking, specifically on cellular, and will be joined by consumer electronics vendors, which are beginning to see the potential of wireless connectivity in many fields. The entry of computer and consumer electronics vendors into the cellular terminals market will increase competition and will drive ubiquity. Mobile equipment manufacturers will face the threat of new players, which, in some cases, have the skills and technology that they lack. On the standardization side, we see in the worldwide partnership projects that powerful industry alliances and joint ventures are defining standards; the problem is that different alliances support different standards. Moreover,
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supposedly competing alliances often contain the same members. The market is full of competition and collaboration, with players forming numerous alliances in the fear of losing out. The winners will shape the market. In the Internet world we see a differently structured standardizationthat is, widespread and global. Far more contributors drive many standards, which also compete with each other. The following targets can be seen in the relevant industry sectors: • Evolutionary development of technologies for networks and UC
alliances, incorporating different environmentswhich means integration of heterogeneous networks based on IP; • Radio terminal technologies with broadband capabilities in the various environments, multistandard and multifrequency capability via software radio technology, and convergence of digital broadcast technology with 3G mobile network techniques; • Global circulation and intelligent network support of ubiquitous mobile appliances; • Mobile application developments that are content- and locationbased in order to make mobile computing a success. Radio interfaces, which are under research, with wideband capability will bring the transmit signal power further down and will therefore minimize the power consumption. As the required frequency bandwidth will not be available in todays frequency ranges for mobile applications (below 3 GHz), the way forward remains open in the search for solutions that coexist with existing radio systems or that deploy technologies in very high-frequency ranges.
7.8 Researchers Move to 4G Mobile Radio Systems The major uncertainty in the developing market for mobile computing technologies is the level of integration and how it will be achieved. There are two levels of integration: industry structure and technical standards. The two are inseparableto a large extent the first will determine the second. This will also influence research programs. New research programs [11, 12] focus on radio technologies for wider frequency bandwidth, higher bit rates, and more capacity, in order to boost mobile computing towards ubiquity. The ITU has started the discussion on IMT-2000 and systems beyond with a similar focus [13]. Research in Europe
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and Japan has already started in this field. The name fourth generation does not necessarily mean that it employs new network architecture and a new air interface. Fourth generation mainly means that system innovation fulfills requirements regarding service and traffic demand beyond 2010. Breakthrough technologies must be inevitable for both radio and core networks. Transmission bit rate and traffic capacity are the most fundamental parameters in the radio access network. The researchers expectation is that in the future, the information will increase even if users send or receive the same information because they will transmit more complex graphics or videos. There will also be research into other areas, however, which could change some of these assumptions. One of these areas lies in the field of mobile agents, another in the delivery of data and the presentation of content. The Mobile Web
For accessing the Web from a mobile device, microbrowsersparticularly those used in standard handsetsare the most important factor that will extend terminals beyond simple voice capability. There is a need for multimode microbrowsers for ubiquitous Web access, which is independent from device and location. Advanced keyword navigation in browsers will reduce the domain name systems importance in finding Web sitesthe personal Web will come with personalized portals. The Web itself will evolve for multipurpose access, where the same content can be presented on a range of devices. The W3C proposed an HTML + TIME (time interactive multimedia extension) standard that would allow composition of synchronized multimedia Web presentations in HTML documents. They would build upon two new Web data formats: the synchronized multimedia integration language (SMIL) and the resource description framework (RDF) [14]. SMIL and RDF were accepted in 1999 by W3C as the standards for multimedia presentations, which integrate video, sound, text, and other media. Both use XML. Cascading style sheets (CSSs) describe how documents will be presented beyond HTML (e.g., screen-based formatting including colors and layout). They significantly improve Web access related to handheld displays. XSL is able to transform document layout for multipurpose publishing in order to achieve device-independency. As a consequence, XML might be used in the future mainly for document management and at the interfaces between loosely coupled systems. As many different types of wearable devices will be developed and will have the potential to bring major benefits to users in the form of value-added services, the mobile operators will be in a key role for the following:
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• The provision of Internet content; • Third-party involvements; • Branding and promoting services at the handset level; • New approaches to customer care.
For situation-dependent mobile computing, the relational markup language (RML) will be used for tailoring the specific needs of mobile Internet devices. RML is an XML applicationit describes content through relationships and provides an intermediate format for all markup languages. When a new device, browser, or gateway comes into the market, only a new module has to be developed for communication between the current and the new devices [2].
7.9 Market Development This coming decade will see the emergence of mobile multimedia communication services. Enabling any time, any place connectivity to the Internet is one of the opportunities for UC. In addition to mobile access to the Internet, 3G brings ubiquity. This market opportunity builds on the unique characteristics of combining mobile and Web messaging, by combining individual positioning for content-related location-based services in order to provide personalized information and entertainment opportunities. The increasing data dominance in the traffic flows in contrast to voice communication already happened in the fixed telecoms and Internet world. This will continue on the wireless side since there are more and more mobile usersover half a million every single day. By 2005, more data than voice may flow over mobile networks. This is amazing, considering that mobile cellular networks were almost exclusively voice. Mobile subscribers will benefit from the always-on characteristic and the higher bit rates of 3G. New services providers will navigate many data services. All this development will enforce mobile computing. It is always difficult to do market predictions; the major uncertainty in the developing market for UC is the level of integration and how it will penetrate the market. The Internet brought us a new communication culture. This is the clear picture from the end of the twentieth century. What is the picture of tomorrow? Nobody is able to predict clearly what will happen. It could be a picture from a flexible service-oriented global society, in which the individual
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interacts worldwide with unlimited access to various servers and networked participants, to work offers and cultures. Virtual project teams could be possible with significant developments in the IT sector. Internet will evolve to an essential business tool everywhere and will be part of everyday life. The increasing exposure to multimedia and infotainment services at work, at home, and on the move could create the expected market of UC. We hope that, after reading this book, you will share our views on UMTS and mobile computing.
References [1] National Technology Roadmap for Semiconductors, ITRS Update, http://www.public.itrs.net, December 2000. [2] Saha, S., M. Jamtgaard, and J. Villasenor, Bringing the Wireless Internet to Mobile Devices, IEEE Computer Magazine, Vol. 34, No. 6, June 2001, pp. 5458. [3] Kuri, J., and C. Windeck, ZwergenaufstandDie Zukunft des PC, ct Magazin für Computer Technik, Hannover, Germany, Vol. 4, 2000, pp. 150154. [4] Pentland, A., Wearable Computers, IEEE pp. 910; Los Angeles Times, Nov. 29,1999.
Micro, NovemberDecember 1999,
[5] Goodman, D. J., The Wireless Internet: Promises and Challenges, IEEE Computer Magazine, July 2000, p. 39. [6] Hubaux, J. P., and M. Vetterli, Terminodes: Self-Organized Mobile Ad Hoc WANs, IEEE Communications Magazine, Global Communications Newsletter, Vol. 38, No. 9, September 2000, pp. 14. [7] Mobile Ad Hoc Networks Group, IETF, http://www.retf.org/html.charters/manetcharter.html. [8] IPv6 Forum, http://www.ipv6.org. [9] UMTS Forum, UMTS Forum Report, Nos. 9 and 13, The Third Generation MarketStructuring the Service Revenue Opportunities, Part I and II, 1012 Russel Square, London WC1B5EE, United Kingdom, October 2000 and April 2001. [10] Huttori, F., et al., Socialware: Multiagent Systems for Supporting Network Communications, Communications of the ACM, Vol. 42, No. 3, March 1999, pp. 5561. [11] Wireless World Research Forum, http://www.wireless-world-research.org. [12] Varshney, U., and R. Jain, Issues in Emerging 4G Wireless Networks, IEEE Computer Magazine, Vol. 34, No. 6, June 2001, pp. 9496.
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[13] ITU, IMT-2000, Report of the Fourth Meeting of ITU-R Working Party 8F, International Telecommunication Union, Radio Communication Study Group, Rabatt, February 2127, 2001, pp. 266288. [14] Lie, H. W., and J. Saarela, Multipurpose Web Publishing Using HTML, XML and CSS, Communications of the ACM, October 1999, Vol. 42, No. 10, pp. 95101.
List of Acronyms 1G first-generation mobile system 2G second-generation mobile system 3G third-generation mobile system 3GPP Third-Generation Partnership Project 4G fourth-generation mobile system A-GPS assisted GPS positioning method AAC advanced audio coding AAL ATM adaptation layer A Interface interface between MSC and BSS AC authentication center ACK acknowledgment ACTS advanced communication technologies and services 387
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ADC automatic data capture AGPS assisted GPS AIDC automatic identification and data capture AMPS advanced mobile phone service (or system) AMR advanced multirate ANSI American National Standards Institute APCO American Police Communication Organization API application program interface APN access point name APT Asia-Pacific Telecommunity ARIB Association of Radio Industries and Business ARPANET Advanced Research Project Agency Network ARQ automatic repeat request ASD authorized software developers ASP application service provider ATDMA advanced time division multiple access ATM
asynchronous transfer mode; automated teller machine
AV audio-video AVI automated vehicle identification AVT automatic vehicle tracking
List of Acronyms
B2B business-to-business B2C business-to-consumer B2E business-to-employee BART Bay Area Rapid Transit BER
bit-error rate
BOL bill of lading bps
bits per second
BPSK binary phase-shift keying BRAN broadband radio access network BRAIN broadband radio access for IP-based networks BSC
base station controller
BSIG Bluetooth Special Interest Group BSS base station system (or subsystem) BSSGP BSS GPRS Protocol BTS base transceiver station BWA
broadband wireless access
CA collision avoidance CAMEL customized application of mobile enhanced logic CAT card application toolkit CD collision detection
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CDG CDMA Development Group CDMA code division multiple access CDMA 2000 multicarrier CDMA CDPD cellular digital packet data CE consumer electronics CEBus consumer electronics business CEPS common electronic purse specification CEPT Conférence Européenne des Adminstrations des Postes et Télécommunications (European Conference of Postal and Telecommunications Administrations) CERN European Organization for Nuclear Research CGALIES Coordination Group on Access to Location Information Services CHIP any bit in a pseudorandom bit stream for modulating information in CDMA cHTML compact hypertext markup language CIDR classless interdomain routing CIF common intermediate format CIS commonwealth of independent states CITEL Inter-America Telecommunication Commission CLC cholesteric liquid crystal CMOS complementary metalloxide silicon
List of Acronyms
CODEC coder/decoder COO cell of origin CORBA
common object request broker architecture
CPU central processing unit CS circuit-switched CSCF call-state control function CSE Canadian Security Establishment CSMA carrier sense multiple access CSMA-CA carrier sense multiple access with collision avoidance CSMA-CD carrier sense multiple access with collision detection CSS cascading style sheets CTIA Cellular Telecommunications Industry Association CWTS China Wireless Telecommunication Standards CXML commerce extensible markup language D2T2 dye diffusion thermal transfer DAB digital audio broadcasting D-AMPS digital version of the North American AMPS analog cellular DAVIC Digital Audio-Visual Council DBS direct broadcast satellite DCA dynamic channel assignment
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DCF distribution coordination function DCS dynamic channel selection DECT digital enhanced cordless telecommunication system DECT Forum Digital Enhanced Cordless Telecommunications Forum DHCP Dynamic Host Configuration Protocol DHTML dynamic hypertext markup language DNS domain name service DOC
U.S. Department of Commerce
DOD U.S. Department of Defense DOT U.S. Department of Transport DS direct sequence DS-CDMA direct sequence code division multiple access DSP digital signal processing (or processor) DRAM dynamic random access memory DSSR digital short-range radio DSSS direct sequence spread spectrum DTX discontinuous transmission DVB digital video broadcasting DVD digital video disc EAS electronic article surveillance
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EBU European Broadcasting Union EC European Commission EDGE enhanced data rates for GSM evolution EDH electronic document handling EDI electronic data interchange EDIFACT electronic data interchange for commerce and trade EEPROM electrically erasable programmable read-only memory EGSM extended global system for mobile communications EIR equipment identity register EGSN enhanced GPRS support mode EIRP equivalent isotropically radiated power EIA/TIA Electronics Industries Association/Telecommunication Industries Association EMC electromagnetic compatibility (or control) EMS enhanced message service EMSC enhanced MSC EMV
Europay/MasterCard/Visa
ENUM extended numbering Internet DNS EOTD enhanced observed time difference EPOC Symbian operating system for small appliances EPROM erasable programmable read-only memory
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ERC European Radio Committee Erlang a dimensionless unit of average traffic density ERO European Radiocommunications Office ERP enterprise resource planning ESS extended services set ETNO Association of European Public Telecommunications Network Operators ETO European Telecommunications Office ETSI European Telecommunication Standards Institute EU European Union EUTELSAT European Telecommunications Satellite Organization FA foreign agent FCC Federal Communications Commission FDD frequency division duplex FDMA frequency division multiple access FEC forward error correction FH frequency hopping FH-CDMA frequency hopping code division multiple access FHSS frequency hopping spread spectrum FOMA freedom of mobile multimedia access FPLMTS future public land mobile telecommunications system (renamed IMT 2000)
List of Acronyms
FRAM ferroelectric random access memory FRAMES future radio multiple access scheme FTP File Transfer Protocol FXP flexible XML processing profile GAP Generic Access Profiles (or Protocol) Gbps gigabits per second GCF Global Certification Forum GEO geostationary Earth orbit GERAN GSM EDGE radio access network GGSN gateway GPRS support node GFI generic format identifier GHz gigahertz GIF Graphics Interchange Format GIOP
General Inter-ORB Protocol
GIS geographical information system GMM global mobile multimedia GMPCS global mobile personal communication by satellite GMSC gateway mobile services switching center GMSK Gaussian minimum-shift keying GNSS global navigation satellite system
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GPS global positioning system GPRS general packet radio service GSA Global Mobile Suppliers Association GSM MS GSM mobile station GSM global system for mobile communications GSM1800 GSM operating at 1.8 GHz (formerly DCS1800) GSM1900 GSM operating at 1.9 GHz GSMA Global System Mobile Association GSN GPRS support nodes GSO geostationary orbit GTP GPRS Tunneling Protocol GUI
graphical user interface
GWY gateway H2GF HIPERLAN/2 Global Forum HA home agent HAN home area network HAPS high-altitude platform station HAVi
home audio-video interoperability
HCR high chip rate HD-MAC high-definition multiplexed analog component HDML handheld device markup language
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HDTV high-density TV HIPERLAN high-performance radio local access network HIPERLAN 2 high-performance radio local access network type 2 (operating in the 5-GHz band) HLR home location register HomePNA
Home Phoneline Networking Alliance
HomeRF Home Radio Frequency Standard HPnP home plug and play HR half rate HSCSD high-speed circuit-switched data HSDPA high-speed downlink packet access HTML hypertext markup language HTTP Hypertext Transfer Protocol HVAC heating ventilation air conditioning Hz hertz IAB Internet Architecture Board IANA Internet Assigned Numbers Authority IC integrated circuit ICANN Internet cooperation of assigned names and numbers ICT information and communications technologies ID identification
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IDEN integrated digital enhanced network IEC International Electrotechnical Commission IEEE
Institute of Electrical and Electronics Engineers
IETF Internet Engineering Task Force IIN issue identification number IIOP Internet Inter-ORB Protocol IMEI international mobile equipment identity IMS IP-based multimedia services IMSI international mobile subscriber identity IMT2000 international mobile telecommunications 2000 IMT intelligent multimode terminal IMT international mobile telecommunications IN intelligent network INMARSAT International Marine Satellite Organization IP Internet Protocol IPNG Internet Protocol next generation IPR intellectual property right IPsec IP security standard IPv4 Internet Protocol version 4 IPv6 Internet Protocol version 6
List of Acronyms
IR infrared IrDA infrared data association IS-95 CDMA interim standard originated by Qualcomm IS-136 industry standards 136 ISDN integrated service digital network ISM industrial-scientific-medical ISMA Internet streaming media alliance ISO International Organization for Standardization ISP Internet service provider IST information society technology ISUP ISDN user part IT information technology IT&T information technology and telecommunications ITU International Telecommunication Union ITU-D ITU Development Sector ITU-R ITU Radiocommunication Sector ITU-T ITU Telecommunication Standardization Sector IWF interworking function JDBC Java database connection JDK Java development kit
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JEEC Joint ECMA/ETSI Program Committee JIT just-in-time JPEG Joint Photographic Experts Group JSP Java server page JTC Broadcasting Joint ETSI/EBU/CENELLEC Committee JVM Java virtual machine kb kilobit KB kilobyte kbps kilobits per second kHz kilohertz kW kilowatt LAN local area network LANS local area network services LBS location-based service LCD long constrained delay; liquid crystal display LCR low chip rate LEO low-Earth orbit LFS location fixing schemes LLC logical link control LMDS local multipoint distribution system
List of Acronyms
LMSC IEEE P802 LAN/MAN Standards Committee LMDS local multipoint distribution system M mega MAC medium access control MAN metropolitan area network MANET mobile ad hoc network MAP mobile application part MB megabyte Mbps megabits per second MC-CDMA multicarrier CDMA Mcps megachips per second MDI Mobile Data Initiative MDS multipoint distribution services MEG Mobile Experts Group MEO medium Earth orbit MExE mobile station application execution environment MGCF media gateway control function MGW media gateway MHz megahertz MIK mobile Internet kit
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MIPS million instructions per second MIT Massachusetts Institute of Technology MMDS microwave multichannel distribution system MMI man-machine interface MMS multimedia message services MNO mobile network operator MoU memorandum of understanding MPEG Moving Pictures Experts Group MRP market representation partner ms millisecond MS mobile station MSC mobile switching center MSISDN mobile station international ISDN number MSS mobile satellite services MultOS multiapplication smart-card operating system MVNO mobile virtual network operator mW kilowatt N-AMPS narrowband advanced mobile phone system NAT network address translation NC network computer
List of Acronyms
NIST National Institute of Standards NMT Nordic Mobile Telephone System NS network service NTIA National Telecommunication and Information Administration OAS Organization of American States OCF OpenCard Framework ODMA opportunity-driven multiple access OEM original equipment manufacturer OFDM orthogonal frequency-division multiplexing OFDMA orthogonal frequency-division multiplexing access OMA object management architecture OMG object management group OQPSK offset staggered quadrature phase-shift keying ORB object request broker OS operating system OSGI Open Services Gateway Initiative OSI open systems interconnection OTDOA observed time difference of arrival OWL object-oriented workplace laboratory P2P peer-to-peer
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PACS public access cordless system PAD portable access device PAMR public access mobile radio PAN personal area network PC personal computer PCB printed circuit board PCF point coordination function PCG Project Coordination Group PCIA Personal Communications Industry Association PCM pulse code modulation PCMCIA Personal Computer Memory Card International Association PCN personal communication network PCS personal communication service PC/SC personal computer/smart card PDA personal digital assistant PDC personal digital cellular PDF Portable Document Format PDN public data network PDP Packet Data Protocol PDU protocol data unit
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PHP personal handyphone PHS personal handyphone system PIAD personal information assistant device PIM
personal information manager
PIN personal identification number PITAC Presidents Information Technology Advisory Committee PKI public key infrastructure PLMN pubic land mobile network PM phase modulation PML procedural markup language PMR private mobile radiocommunciations PN personal number PoP point of presence PoS point of sale POSI Promotion Conference for Open System Environment and Interoperability POTS plain old telephone service PROM programmable read-only memory PS paging system; packet-switched PSE packet-switching exchange
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PSK phase-shift keying PSN public switched network PSPDN packet-switched public data network PSTN public switched telephone network PSU power supply unit PTC Pacific Telecommunication Council PTT post telephone and telegraph PVC permanent virtual circuit QAM quadrature amplitude modulation QAPSK quadrature amplitude phase-shift keying QCIF quarter common intermediate format QoS quality of service QoT quality of transport QPSK quadrature phase-shift keying RAB random access burst RACE research and development in advanced communication for Europe RACH random access channel RAINBOW radio access independent broadband on wireless RAM random access memory RAS remote access server
List of Acronyms
RAST global radio standardization RDF resource description framework RDS radio data system RF radio frequency RFID radio frequency identification RISC reduced instruction set computer RLAN radio-based local area network RLL radio in the local loop RLP Radio Link Protocol RMI remote method invocation RML relational markup language RNC radio network controller ROM read-only memory ROS remote operation services RP radio part RPC remote procedure call RPOA recognized private operating agency RTP Real-Time Transport Protocol RTSJ real-time specification for Java RTT radio transmission technology
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SAT SIM application toolkit SAT-PCN satellite personal communications network SCCP signaling connection control part SCF service control function SCSL Sun community source license SCTP Stream Control Transmission Protocol S-DAB satellite digital audio broadcasting SDH synchronous digital hierarchy SDL specification description language SDMA space division multiple access SDMI Secure Digital Music Initiative SDO standardization development organization SDP Session Description Protocol (IETF) SDR software-defined radio SES ETSI Satellite Earth Station Committee SGML standard generalized markup language SGSN
serving GPRS support node
SIG special interest group SIM subscriber identity module SIP Session Initiation Protocol
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SITA Societé Internationale de Télécommuntions Aéronautiques (International Society of Aeronautical Telecommunications) SMG ETSI Special Mobile Group SMIL synchronized multimedia integration language SMS Satellite Multiservice System SMS short message service SMTP Simple Mail Transfer Protocol SNDCP Subnetwork Dependent Convergence Protocol SOAP Simple Object Access Protocol SONET synchronous optical network SQAM staggered quadrature amplitude modulation SQPSK staggered quadrature phase-shift keying SRAM
static random access memory
SS7 Signaling System No. 7 SSL secure socket layer SSP service switching point SSS subscriber switching subsystem SWAP Shared Wireless Access Protocol STP signaling transfer point TACOM Tank-Automotive and Armaments Command
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TACS total access communications system TASI time assigned speed interpolation TCAP transaction capabilities application part TCH traffic channel TCH/F full-rate TCH TCH/FS full-rate speech TCH TCH/H half-rate TCH TCP Transmission Control Protocol TCP/IP Transmission Control Protocol/Internet Protocol TD/CDMA combination of TDMA and CDMA TDD time division duplex TDMA time division multiple access TDOA time difference of arrival TD/SCDMA combination of TDMA and CDMA with smart antenna TETRA trans-European trunked radio TETRAPOL digitized PMR standard TIA Telecommunication Industry Association TIME time interactive multimedia extension TIMES telecommunication, information, multimedia, entertainment, security
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TINA-C Telecommunication Information Networking Architecture Consortium TINI tiny Internet interface TLD top-level domain name TLS transport layer security (IP standard) TOA time of arrival TRX transceiver TSAP transport service access point TSG Technical Specification Group TSIQPSK two symbol interval quadrature phase-shift keying TTA Telecommunication Technology Association TTC Telecommunications Technology Committee TV television Ubicomp ubiquitous computing UC ubiquitous computing UDD unconstrained delay data UDI unrestricted digital information UDP User Datagram Protocol UICC universal integrated circuit card UMS unified messaging service UMTS universal mobile telecommunication system
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UPC
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universal product code
UPCS unlicensed personal communication service UPnP universal plug and play UPS United Parcel Service UPTN universal personal telecommunications number URL uniform resource locator URN uniform resource name USAT universal SIM application toolkit USB universal serial bar USDC U.S. digital cellular USIM universal subscriber identity module UTRA universal terrestrial radio access UTRAN universal terrestrial radio access network UWB ultra wideband UWC universal wireless communication UWCC Universal Wireless Communication Consortium VCR videocassette recorder VHE virtual home environment VLR visitor location register VMS voice message system
List of Acronyms
VoIP Voice over Internet Protocol VPN virtual private network VSAT Forum Very Small Aperture Satellite Transmission Forum VTP Virtual Terminal Protocol VXML voice XML W3C World Wide Web Consortium WAN wide area network WAP Wireless Application Protocol WAP Forum Wireless Application Protocol Forum WARC World Administrative Radio Conference WATM wireless asynchronous transfer mode WB wideband WBMP Wireless bitmap (graphic format) W-CDMA wideband code division multiple access WCML Web composition markup language WDP Wireless Datagram Protocol WECA Wireless Ethernet Compatibility Alliance WILL wireless in local loop WIN wireless intelligent network WIP work in process
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WLAN wireless local area network WLIF Wireless LAN Interoperability Forum WLL wireless local loop WMA Windows media audio WML wireless markup language WORM
write-once-read-many
WPAN wireless personal area network WPKI wireless public key infrastructure WRC World Radio Conference WSP Wireless Session Protocol WTAC ITU World Telecommunication Advisory Council WTLS Wireless Transport Layer Security/WAP Protocol WTO World Trade Organization WTP Wireless Transportation Protocol WWW World Wide Web WTPF ITU World Telecommunication Policy Forum XHTML extensible hypertext markup language XML extensible markup language XSL extensible style sheet language X/Open Unix Open Applications Group XIWT cross-industry working team
About the Authors Alexander Joseph Huber, born in 1976 in Germany, studied computer science with specializations in electrical engineering and communications at the Technical University (TUM), Munich, Germany, and at the École Polytechnique in Paris, France. He finalized his studies in 2000 with an M.S. in computer science. During his studies, Mr. Huber was deeply involved in many fields of computer science and telecommunication networks. In particular, he was a designer and developer of official Web sites, as well as Web master and editor of a multilingual guide to Munich on the Web, and made several contributions to university publications. In 1996, he created the first UMTS Forum Web site, as well as the DECT Forums site. Concurrently, he was busy with electronic signatures and digital watermarking, Web multithreaded proxy and Web servers, e-mail applications and databases, and graphical user interfaces (GUIs), as well as advanced GUIs for Web searches. Further, he put much effort into ubiquitous computing (UC), small information appliances and their applications, (mobile) e-commerce, mobile Internet and telematics, as well as context-dependent location-based services in telecommunication networks, mobile services, UMTS, service discovery, service utilization, and architectures. Mr. Huber started his professional career at Siemens AG in 1992. While studying in France, he worked at the École Nationale Supérieur des Mines de Paris. Next, he worked for AltaVista Search in California, developing a high-level navigation interface for Web searches using the AltaVista search engine. Back in Europe in 1998, he worked as a research student at 415
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the TUM at the Institute of Communication Networks, developing a prototype for IP telephony and VoIP for distributed systems using CORBA. Finally, before finishing his studies, he worked as a research student at the DaimlerChrysler Research and Technology Center, North America, where he did his masters thesis on UC, information appliances, and applications. In 2001 Mr. Huber joined the Institute of Communication Networks of Professor Eberspächer at TUM as a member of the research staff. He researched and published in the field of mobility- and context-dependent location-based services, in addition to teaching and examining students in computer science. Today, he works at the European Patent Office. He is a member of IEEE, the Computer Society, and the Association for Computing Machinery. Josef Franz Huber, born in Austria in 1939, studied electrical engineering in Innsbruck and Vienna, Austria, and finalized his studies in 1965 with an M.S. from the Technical University in Vienna. In 1965 he joined the Siemens Central Laboratories in Munich, Germany, for the development of the first Siemens stored-program-controlled text-and-data switch EDS. Subsequently, he was responsible for network and system planning in the field of text-and-data communication for several years. In the 1970s, the early years of Internet Protocol development, he joined the packet-switching developments of products for public data-communications networks in the United States and Europe. Under his tenure as head of development, a number of X.25 networks were put into service in the United States, Europe, Asia, and Africa. In 1980, Mr. Huber became head of the text-and-data development department for circuit- and packet-switching technology, e-mail services, and for the Kopernikus satellite data-communications system. From 1987 to 1990 his work focused on broadband metropolitan area networks. In 1990 Mr. Huber moved to the mobile network sector, where he built up a mobile development group in Munich and Berlin, Germany, and where he also assumed responsibility for GSM data-service developments and radio-related issues. Presently, Mr. Huber is active as senior vice president of the mobile network business unit at Siemens. He is well known for his international involvement as speaker, panelist, and session chairman at a number of conferences (ISS, ICCC) and for his more than 200 technical publications in magazines, books, and conference proceedings. He was chairman of the mobile group of the German electrotechnical industry association ZVEI. From 1996 to 1998, he chaired the experts group of the UMTS Forum, dealing with global spectrum calculations, methodologies, and traffic models.
About the Authors
417
This team was strongly involved in the preparations for the ITU World Conference 2000, which resulted successfully in additional frequency spectrum for 3G mobile services. He was deeply involved in the conceptual work for UMTS, which resulted in a number of agreements for IMT-2000 spectrum worldwide and in the extended UMTS vision, the migration of mobile technologies with the Internet. He is vice chairman of the UMTS Forum dealing with 3G mobile multimedia issues for global applications. His further involvement lies in the German industry association BITKOM as the acting chairman for the mobile industry sector.
Index addressing, 26162, 339, 342 future, 371, 372, 375 mobile, 37374 smart device, 22526 spectrum demand, 35961 Advanced audio coding, 26768 Advanced communications technologies, 71 Advanced global positioning system, 123 Advanced Mobile Phone Service (IS-54), 39, 55, 65, 6770 Advanced multirate codec, 265 Advanced RISC Machines, 20910 Advertising services, 332 Afro-Asian Satellite Communications, 93 AIDC. See Automatic identification and data capture Air interface, 6467, 106, 366. See also Access techniques All-in-one mobile device, 23334 Always-on connection, 76, 255, 26061, 341, 383 American Mobile Satellite Corporation, 94 American National Standardization Institute, 242, 375 AMPS. See Advanced Mobile Phone Service AMR. See Advanced multirate codec
AAC. See Advanced audio coding AAL2. See ATM adaptation layer 2 AC. See Authentication center Access controller, 5758 Access point, 57, 62 Access point name, 105 Access techniques integration, 37273 mobile Internet, 3046 UMTS, 11020 wireless WAN, 6467 ACeS. See Asia Cellular Satellite Active backspatter frequency identification tag, 173, 231 Active Movie, 274 Active radio frequency identification tag, 17273 ACTS. See Advanced communications technologies Adaptive multirate voice codec, 11 ADC. See Automatic data capture Addressing, 8, 56, 126, 12627, 131, 252, 366, 374 capacity, 335, 33944 Internet, 33638 schemes, 32639 standardization, 252, 25354, 25863 Ad hoc network, 5, 57, 62, 247, 303, 366 419
420
UMTS and Mobile Computing
AMSC. See American Mobile Satellite Corporation Analog-digital conversion, 13 Animal identification, 178, 180, 182, 18586 ANSI. See American National Standardization Institute ANSI X3T6 group, 17778 API. See Application programming interface APMT. See Asia-Pacific Mobile Telecommunications Satellite APN. See Access point name Application, definition of, 304 Application programming interface, 125, 137, 277, 281, 283 Applications, new, 37879 Application service provider, 319, 372 Application-specific mobile device, 233 APT. See Asia-Pacific Telecommunity ARIB. See Association of Radio Industry and Business ARM. See Advanced RISC Machines ARPANET, 23, 24, 242 ARQ. See Automatic repeat request Artificial intelligence, 12 ASC. See Afro-Asian Satellite Communications ASD. See Authorized software developer Asia, 81, 192, 250 Asia Cellular Satellite, 93 Asia-Pacific Mobile Telecommunications Satellite, 93 Asia-Pacific Telecommunity, 356 ASP. See Application service provider Association of Radio Industry and Business, 72, 82, 242, 250, 375 Asymmetric traffic, 34647, 348, 352 Asynchronous transfer mode, 119 ATM. See Asynchronous transport mode ATM adaptation layer 2, 11920 Audio communication. See Multimedia communication Audio compression, 266, 26774 Authentication, 58, 109, 121, 128, 232, 377 Authentication center, 75
Authorized software developer, 167 Automated vehicle identification, 170 Automatic data capture, 198, 227 Automatic identification and data capture, 148, 150, 168, 170 Automatic repeat request, 118, 119 Automatic vehicle tracking, 184 Automobile-related communication, 36 Automotive industry, 17880. See also Vehicle applications AVI. See Automated vehicle identification AVT. See Automatic vehicle tracking B2B. See Business-to-business B2C. See Business-to-consumer B2E. See Business-to-employee Backspatter frequency identification tag, 173 BadgePAD, 185, 187 Banking services, 333 Bar-code technology, 16970, 232 Base station, 5455, 75 Base station controller, 75 Base station system, 75 Base transceiver station, 75 Beamforming, 14, 124 Bedside admitting, discharge, and transfer, 328 Bedside drug-use evaluation, 32829 Berkeley Wireless Research Center, 373 Billing solutions, 7576, 136 Biometrics, 204, 377 BiStatix, 187 Bitmap encoding, 26566 Bit rate, 39, 41, 58, 7677, 99100, 108, 11417, 368, 369, 373, 382 BlueSky, 48 Bluetooth, 22, 34, 35, 36, 39, 4348, 53, 99, 199, 202, 210, 216, 223, 225, 226, 243, 245, 26162, 283, 375, 376 Bluetooth Special Interest Group, 45, 100, 242, 243, 262 Bluetooth version 2, 47 BRAIN. See Broadband radio access for IP-based network
Index BRAN. See Broadband radio access network Broadband, definition of, 80 Broadband radio access for IP-based network, 58, 6162, 37273 Broadband radio access network, 34, 60 Broadband wireless access, 7980 Broadband wireless convergence, 3435 Broadcast and flooding, 26263 Broadcasting convergence, 35 Browsers, 21113 BSC. See Base station controller BSIG. See Bluetooth Special Interest Group BSS. See Base station system BTS. See Base transceiver station Business applications, 22729, 3003, 32933, 369 Business-to-business, 29, 33233 Business-to-consumer, 29, 33233 Business-to-employee, 29, 33233 Business user portals, 13940 BWA. See Broadband wireless access BWA Study Group, 80 C2C. See Consumer-to-consumer Call control, 125, 223 Call setup, 55, 70 Call state control function, 123 CAMEL. See Customized access for mobile enhanced logic Canada, 68 Canadian Security Establishment, 166 Card PC, 204 Card technologies, 14760 Care-of address, 12627, 258 Car organizer, 199 Carrier identification, 179 Carrier sense multiple access/collision avoidance, 60, 248 CCI. See Constellation Communications CDMA. See Code division multiple access cdma2000, 7071, 84, 85, 99 CDPD. See Cellular digital packet data CEbus, 280, 28384 CE device. See Consumer electronic device Cell Computing Card PC, 204 Cell of origin, 123, 313
421
Cell radius, 39 Cellular digital packet data, 39, 6869 Cellular network market, 67, 19395 Cellular Telecommunications Industry Association, 65, 69 CEN CENELEC, 242 CEPS. See Common electronic purse CEPT. See European Conference of Postal and Telecommunications Administrations Channel capacity, 66, 99100, 115 Channel length, 369 China Wireless Telecommunications Standards Institute, 82, 242, 250 Chip card, 15658 Cholesteric liquid-crystal screen, 10 cHTML. See Compact hypertext markup language CIDR. See Classless interdomain routing CIF. See Common intermediate format Circuit-switched domain, 121, 122, 125 Circuit-switched network, 2527, 39, 103, 371 CITEL. See Inter-American Telecommunication Commission Classless interdomain routing, 254, 341 CLC screen. See Cholesteric liquid-crystal screen Client-server system, 13132, 224, 247, 371, 372, 379 Clinical care, 328 Clinical documentation, 32728 CMOS. See Complementary metalloxide silicon C-Net, 68 Cochannel interference, 14 Code division multiple access, 40, 42, 6368, 7072, 84, 85, 115, 351, 368 Collaboration, remote, 302 Combination access schemes, 65, 72, 84, 104, 110, 116, 122 Commerce extensible markup language, 140, 287 Committee T1, 82, 250 Common electronic purse, 292 Common facilities, 277
422
UMTS and Mobile Computing
Common intermediate format, 270 Common object request broker architecture, 129, 213, 216, 275, 27679, 372 Compact hypertext markup language, 284, 285, 286, 320 Complementary metalloxide silicon, 910 Composite bar code, 169 Compression standards, 1112, 26364, 26674, 36869 Comsat, 94 Configurable radio. See Software-defined radio Connectivity, 194 Constellation Communications, 91, 93 Consumer electronic device, 51, 198 Consumer electronics business, 188 Consumer-oriented portal, 140 Consumer-to-consumer, 33233 Contactless smart card, 15758, 232, 377 Contact smart card, 157, 16062 Content-based interactivity, 1112 Content delivery services, 33132 Content-oriented portal, 133 Content presentation, 20 Content provider, 317 Context-aware device, 204, 226, 37879 Control layer, 121 Convergence computer/telecommunication/ media, 22425, 36569, 372, 375 device, 3536, 230, 37577 fixed and mobile, 3036, 19395 Convergence-oriented portal, 133 COO. See Cell of origin Coordination Group on Access to Location Information by Emergency Services, 313 CORBA. See Common object request broker architecture Corporate sector, 22729, 3003, 317, 369. See also Business applications Cost factors, 105, 176 Crisis management, 302 Cryptographic iButton, 16467 CSCF. See Call state control function CSE. See Canadian Security Establishment
CSMA/CA. See Carrier sense multiple access/collision avoidance CTIA. See Cellular Telecommunications Industry Association Customer segmentation, 18 Customized access for mobile enhanced logic, 10910, 124, 295 Customized services, 3067 CWTS Institute. See China Wireless Telecommunications Standards Institute CXML. See Commerce extensible markup language DAB. See Digital audio broadcast DAMPS. See Digital Advanced Mobile Phone Service Data capture device, 203 Data capture services, 196 DBS. See Direct broadcast satellite DCA. See Dynamic channel allocation DCF. See Distribution coordination function DCS. See Dynamic channel selection DCS 1800, 88, 141 DECT. See Digital enhanced cordless telecommunication Device convergence, 3536, 230, 37577 Device-interconnection network, 191 Device network, 191 Devices third-generation, 192230 ubiquitous computing, 14547 DHCP. See Dynamic Host Configuration Protocol DHTML. See Dynamic hypertext markup language Digital Advanced Mobile Phone Service (IS-136), 40, 6870, 99, 14142 Digital Angel, 185, 186 Digital audio broadcast, 31, 35 Digital enhanced cordless telecommunications, 2022, 39, 4849, 52, 5356, 64, 141, 24950 Digital jewelry, 167 Digital products, 98
Index Digital short-range radio, 78 Digital signal processing, 13, 221 Digital video broadcasting, 10, 31, 35 Digital video disc, 26869, 271, 369 Direct broadcast satellite, 270 Directory services, 137 Direct sequence spread spectrum, 58, 59, 248 Discovery agent, 279 Display technology, 10 Distribution coordination function, 60 Djinn, 275 DNS. See Domain name service Domain interface, 277 Domain name service, 336, 337, 338, 339, 341 Download, application and service, 143 DSP. See Digital signal processing DSRR. See Digital short-range radio DSSS. See Direct sequence spread spectrum Dual-mode telephone, 91 Dual-mode terminal, 70, 8889, 90, 1078, 221 Duplex distance, 113 DVB. See Digital video broadcasting DVD. See Digital video disc Dye diffusion thermal transfer, 15960 Dynamic channel allocation, 78, 118 Dynamic channel selection, 55, 56, 88, 141 Dynamic Host Configuration Protocol, 341 Dynamic hypertext markup language, 284 Dynamic invocation interface, 278 Dynamic skeleton interface, 278 EAS. See Electronic article surveillance EAST. See Euro-African Satellite Telecommunications System E-commerce. See Electronic commerce EDGE. See Enhanced data rates for GSM evolution EEPROM, 153, 206 EIA/TIA. See Electronics Industries Association/Telecommunication Industries Association EIR. See Equipment identity register
423
EIRP. See Equivalent isotropically radiated power Electronic article surveillance, 173, 178 Electronic commerce, 29, 137, 227, 292, 32933, 377 Electronic identity, 188 Electronics Industries Association/ Telecommunication Industries Association, 6870 Electronic toll collection, 186 Ellipso, 91, 93 E-mail, 23, 28, 102, 137, 202, 203, 258, 275, 299, 350 Embedded microprocessor, 4, 204, 371, 373 Emergency services, 311, 313 EMS. See Enhanced message service EMV. See Europay/MasterCard/Visa Encoding standardization, 26374 End-to-end user connection, 26 Enhanced data rates for GSM evolution, 1819, 72, 74, 7677, 84, 85 Enhanced data services, 17 Enhanced message service, 101, 123, 202, 265, 308, 309 Enhanced observed time difference, 313, 314 Enterprise applications, 22630 Enterprise resource planning, 22730 Entertainment applications, 3067 ENUM. See Extended numbering Internet DNS EOTD. See Enhanced observed time difference EPOC Opera Browser, 213 EPOC operating system, 198, 201, 202, 207, 20910 EP SCP. See ETSI Project Smart Card Platform Equipment identity register, 75 Equivalent isotropically radiated power, 363 ERC. See European Radio Committee Ericsson R380, 202 Erlang formulas, 115 ESS. See Extended services set
424
UMTS and Mobile Computing
Ethernet, 60, 280 ETSI. See European Telecommunication Standards Institute ETSI Project Smart Card Platform, 294 Euro-African Satellite Telecommunications System, 94 Europay/MasterCard/Visa, 29192 Europe, 34, 53, 5960, 65, 7172, 7879, 8183, 110, 118, 151, 153, 192, 225, 242, 250, 270, 324, 35358, 36162, 377, 38182 European Commission, 71, 82, 8283 European Conference of Postal and Telecommunications Administrations, 59, 355, 356, 361 European Radio Committee, 60, 356 European Telecommunication Standards Institute, 34, 53, 60, 65, 7172, 82, 110, 118, 242, 243, 250, 279, 295, 373, 375 European Union, 72, 95 Extended area network, 8696, 99 Extended numbering Internet DNS, 340 Extended services set, 359, 360 Extended vision mobile Internet, 1067 Extensible hypertext markup language, 135, 138, 140, 144, 28586, 28889, 319 Extensible markup language, 135, 140, 217, 275, 276, 28486, 28789, 382, 383 Extensible stylesheet language, 285, 287, 382 EZOS EZWAP browser, 213
FireWire, 95, 9798, 281 First-generation mobile network, 4, 1819, 6768 Fixed network convergence, 3036 Fixed network address, 259, 34041, 342 Foreign agent, 128 Fourth-generation mobile radio, 38183 Fractal coding, 269 FRAM. See Ferroelectric read-only memory FRAMES. See Future radio multiple access Frequency allocation. See Spectrum allocation Frequency division duplex, 67, 72, 84, 104, 11014, 116, 118, 120, 350 Frequency division multiple access, 6369 Frequency division multiplexing, 80 Frequency hopping, 43, 45 Frequency hopping spread spectrum, 58, 59, 248 Frequency reuse, 67, 76, 119 Frequency spectrum ad hoc network, 35961 barriers versus capacity, 34446 licensing, 2122, 9899 market trends, 98100, 381 radio frequency, 17475 satellite system, 9092 third-generation, 335, 34653 UMTS, 101, 359 WLAN, 35963 worldwide identification, 35358 FTP. See File Transfer Protocol Full-rate voice codec, 11 Future radio multiple access, 7172 Fuzzy logic, 12
FA. See Foreign agent Facsimile, 91, 92 FDD. See Frequency division duplex FDMA. See Frequency division multiple access Ferroelectric read-only memory, 172 FHSS. See Frequency hopping spread spectrum File Transfer Protocol, 25, 134, 256, 275 FIPS 140-1 validation, 166 Firefly, 100
Galileo, 95, 314 GAN. See Global area network GAP. See Generic access profile Gateway GPRS support node, 76, 105, 124, 125, 127 GCF. See Global Certification Forum General Inter-ORB Protocol, 278 General packet radio service, 1819, 41, 73, 74, 7576, 101, 255, 258 Generic access profile, 43, 52 Generic CAT, 294
Index GEO. See Geostationary earth orbit Geographical information system, 302 Geostationary Earth orbit, 8788, 93, 94 Geoworks GEOS, 207, 211 GERAN. See GSM-Edge Radio Network GGSN. See Gateway GPRS support node GIF. See Graphics interchange format GIOP. See General Inter-ORB Protocol GIS. See Geographical information system Global area network, 91 Global Certification Forum, 259 Global domain name, 337, 340, 344 Global Mobile Suppliers Association, 251, 356 Global Partnership Projects, 242 Global positioning system, 9495, 204, 302, 31314 Globalstar, 87, 91, 92 Global System for Mobile Communications, 6, 35, 39, 40, 42, 55, 58, 66, 115, 120, 129, 201 interoperability, 14142 network components, 72, 7475 spectrum allocation, 99 standardization, 7274, 265 Global System for Mobile Communications 900, 88 GPRS. See General packet radio service GPRS support node, 122, 12627 GPRS Tunneling Protocol, 105, 127, 129 GPS. See Global positioning system Graphical user interface, 209 Graphic encoding, 26566 Graphics interchange format, 265 GSA. See Global Mobile Suppliers Association GSM. See Global System for Mobile Communications GSM Association, 74, 251, 356 GSM-Edge Radio Network, 122, 251 GSM supplementary services, 73 GSN. See GPRS support node GTP. See GPRS Tunneling Protocol GUI. See Graphical user interface H.261 algorithm, 12 H.263 algorithm, 12
425
HA. See Home agent Half-rate voice codec, 11 HAN. See Home area network Handheld device, 192, 193, 19498, 2003, 22526, 233, 306 Handheld device markup language, 290 Handheld Navigator, 95 Handheld shopping, 331, 333 Handover, 41, 54, 56, 67, 89, 119, 128, 373 Handset, 2001, 203 Handwriting recognition, 10, 19899, 376 HAPS. See High-altitude platform station Hard real-time application, 206 HAVi. See Home audio-video interoperability HCR. See High chip rate HD-MAC. See High-definition multiplexed analog components HDML. See Handheld device markup language Header structure, 254 Health care applications, 18485, 187, 301, 32629, 377 Hetero-bipolar transistor, 36970 High-altitude platform station, 42, 95, 96, 99, 358 High bit rate, 76 High chip rate, 72, 113, 119, 350 High-definition multiplexed analog components, 270 High-performance radio local access network, 22, 34, 39, 49, 6062, 99, 359, 363 High-performance radio local access network 2, 6162, 361, 373 High-performance radio local access network 3, 61 High-speed circuit-switched data, 73, 74, 108 High-speed downlink packet access, 119, 124, 125, 141 HIPERACCESS, 61 HIPERLAN. See High-performance radio local access network HIPERLAN Forum, 61, 242, 375 HLR. See Home location register
426
UMTS and Mobile Computing
Holographic display, 10 Home access, 303 Home agent, 12627, 128, 189 Home appliance technology, 18892, 205 Home area network, 38, 4853, 98, 31617 Home audio-video interoperability, 48, 188, 275, 276, 28082, 283 Home location register, 75, 122, 126 Home Phoneline Networking Alliance, 48, 280, 283 Home Plug and Play, 276, 28384 HomePNA. See Home Phoneline Networking Alliance Home radio frequency, 48, 51, 5253, 100, 283 HomeRF. See Home radio frequency HomeRF Working Group, 100 Horizontal common facilities, 277 Hospital applications, 32629 HPnP. See Home Plug and Play HSCSD. See High-speed circuit-switched data HSDPA. See High-speed downlink packet access HTML. See Hypertext markup language HTTP. See Hypertext Transfer Protocol HVAC applications, 189 Hybrid card, 148 Hypertext markup language, 135, 138, 140, 144, 212, 217, 28490, 322, 382 Hypertext Transfer Protocol, 25, 105, 134, 214, 256, 275, 276, 322, 338 IANA. See Internet Assigned Numbers Authority iButton, 16068, 23031 IC. See Integrated circuit ICANN. See Internet Corporation for Assigned Names and Numbers ICO, 91, 9293 iDEN, 219 Idle voice channel, 68 IEC. See International Electrotechnical Commission
IEEE. See Institute of Electrical and Electronics Engineers IEEE P802 LAN/MAN Standards Committee, 245 IETF. See Internet Engineering Task Force IETF Working Group, 340 IGate, 63 IIOP. See Internet Inter-ORB Protocol IMAP. See Internet Message Access Protocol IMEI. See International mobile equipment identifier i-mode, 20, 101, 134, 138, 243, 265, 284, 286, 3067, 318, 32022, 332 IMSI. See International mobile subscriber identity IMT-2000. See International Mobile Telecommunications 2000 Individual mobility, 3233 Industrial applications, 17980, 22729 Information-based services, 134, 368 customized, 3067 data transfer time, 26365 UMTS, 1035 Information encoding, 26374 Information Society Technology, 61 Information technology, 38081 Infostation, 302, 373 Infrared, 38 Infrared Data Association, 9596, 193, 202, 243, 248 Inmarsat, 87, 91, 92, 94 Innovation drivers, 916 Instant messaging service, 102, 124, 125, 30910 Institute of Electrical and Electronics Engineers, 34, 43, 243, 245, 375 802.11 standards, 34, 39, 49, 52, 5760, 6263, 24649, 26263, 359, 361 802.11a standard, 59 802.11b standard, 5960, 6263, 246 802.15 standard, 39, 5253, 24546, 261 802.16 standard, 7980 802.3 standard, 62 1394 standard, 48, 95, 9798, 280, 281
Index Integrated circuit chip, 185 Integrated circuit memory card, 15859 Integrated circuit microprocessor card, 15658 Integrated circuit smart card, 15354, 232 Integrated services digital network, 21, 74, 115, 26364 Intelligent agent, 12, 325 Intelligent pen, 376 INTELSAT, 94 Inter-American Telecommunication Commission, 356 Intercell handover, 54 Interference, 39 International Electrotechnical Commission, 260, 265, 26669 International mobile equipment identifier, 25960, 261 International mobile subscriber identity, 90, 127 International Mobile Telecommunications 2000, 15, 32, 40, 54, 70, 8183, 100, 106, 242, 375, 381 International Mobile Telecommunications 2000 combination schemes, 84 International roaming, 17 International Standards Organization, 11, 178, 242, 260, 264, 265, 26669 International Telecommunication Union, 1112, 15, 21, 8185, 99, 106, 242, 259, 266, 269, 381 E.164 standard, 56, 123, 33637, 339 International Telecommunication Union Radiocommunication Sector, 8283, 118, 354, 355, 356 International Telecommunication Union Telecommunications Sector, 90 Internet, 4, 69, 10, 151 access, 2728, 91 addressing, 336, 33738 future developments, 368, 38384 growth of, 299300, 341 innovations, 7, 1516, 2230 standardization, 25256 UMTS service, 102, 1035, 108, 12628
427
See also Mobile Internet; Wireless Internet Internet Assigned Numbers Authority, 336 Internet Corporation for Assigned Names and Numbers, 242, 336, 338, 340, 344 Internet Engineering Task Force, 123, 130, 242, 258, 340 Internet Inter-ORB Protocol, 276 Internet Message Access Protocol, 219 Internet portal, 140 Internet Protocol, 8, 23, 52, 58 Internet Protocol multimedia domain, 121 Internet Protocol version 4, 100, 121, 130, 138, 253, 25556, 337, 338, 341, 34243 Internet Protocol version 6, 5, 100, 121, 123, 126, 13031, 138, 217, 25356, 258, 337, 338, 341, 374 Internet service provider, 102, 1035, 108, 12932, 372 Internet Streaming Media Alliance, 265 Interoperability, 18, 42, 57, 72, 99, 14142, 153, 190, 21415, 24849, 294, 303, 308, 329, 366, 377 Intracell handover, 54 Intranet, 7, 15, 2930, 102, 3046 Intranet portal, 13940 IP. See Internet Protocol IP-based network architecture, 101 IPv4. See Internet Protocol version 4 IPv6. See Internet Protocol version 6 IPv6 Forum, 251, 374 IrDA. See Infrared Data Association Iridium, 87, 9192 IS-54 (AMPS), 39, 55, 65, 6770 IS-136 (DAMPS), 40, 6870, 99, 14142 IS-95 standard, 1819, 40, 70 ISDN. See Integrated service digital network ISMA. See Internet Streaming Media Alliance ISO. See International Standards Organization ISP. See Internet service provider Issuer identifier number, 260
428
UMTS and Mobile Computing
IST. See Information Society Technology ITU. See International Telecommunication Union ITU-R. See International Telecommunication Union Radiocommunication Sector ITU-T. See International Telecommunication Union Telecommunications Sector J2ME. See Java 2, Micro Edition Japan, 2021, 39, 65, 70, 7172, 81, 90, 134, 242, 250, 313, 32022, 382 Japan total access communications system, 39 Jataayu WAP browser, 213 Java, 132, 139, 192, 202, 212, 213, 21516, 21719, 233, 275, 279, 281, 29293, 372 Java 2, Micro Edition, 202, 217, 219 JavaCard, 13, 293 Java database connection, 138 Java development kit, 279 JavaRing, 167 JavaScript, 219 Java smart card, 151, 15558, 16062, 16567, 225 JavaSpace, 216 Java virtual machine, 164, 21516 JDBC. See Java database connection JDK. See Java development kit Jellybean machine, 19192 Jini, 205, 213, 21517, 221, 226, 262, 27576, 279, 280, 281, 283, 372 J-machine. See Jellybean machine Joint Photography Experts Group, 11, 26566, 274, 309 Joint Photography Experts Group 2000, 26566, 274 Joint Technical Committee, 265 JPEG. See Joint Photography Experts Group JTACS. See Japan total access communications system JTC1. See Joint Technical Committee JVM. See Java virtual machine KERNEL, 221
Kilobyte Virtual Machine, 219 Korea, 71, 72, 81, 82, 250 KVM. See Kilobyte Virtual Machine LAN. See Local area network Language processing, 10 LAN/MAN Standards Committee, 52, 7980 Laptop computer, 7, 194, 196, 2034, 234 Last-mile problem, 15 Latin America, 68, 78 Laundry applications, 184 LCD. See Long constrained delay LCR. See Low chip rate LEO. See Low-Earth orbit Library applications, 18485 Licensed frequency spectrum, 2122, 9899 License-exempt frequency spectrum, 2122 Linear bar code, 169 Linux Mobile, 19899, 207, 211 LLC. See Logical link control LMDS. See Local multipoint distribution system LMSC. See LAN/MAN Standards Committee Local area network, 2122, 23, 5657, 227, 336 802.11 standard, 24649, 26263 See also Wireless local area network Local multipoint distribution system, 8081 Location-based services, 5, 8, 14, 16, 28, 36, 73, 91, 92, 9495, 101, 123, 133, 136, 137, 140, 178, 182, 278, 31015 Location-dependent applications, 302, 374 Location-fixing scheme, 313 Locus, 313 Logical link control, 256 Long constrained delay, 118, 119 Long-range radio system, 38, 40, 42 Low chip rate, 72, 104, 113, 116, 350 Low-Earth orbit, 8788, 9192 Low-voltage technology, 370 MAC. See Medium access control Macrodiversity, 67
Index Magnetic stripe card, 14850 MANET. See Mobile ad hoc network Man-machine interface, 10, 138, 141, 143 Market developments, 12, 59, 33 convergence, 3536, 19395, 22425, 230, 36569, 37577 future, 38081, 38384 mobile communication, 19297, 22425, 320 networked architecture, 37175 semiconductors, 36971 services and applications, 37879 small, 14647 UMTS, 1005 Marketing services, 332 Market representation partner, 251 Matchbox Server, 204 MCC. See Mobile country code M-commerce. See Mobile electronic commerce Measurement data collection, 332 Media gateway, 121, 123, 25253 Media gateway control function, 123 Medical applications, 18485, 187, 301, 32629 Medication administration, 32829 Medicine cabinet, 327 Medium access control, 52, 60, 248 Medium-Earth orbit, 8788, 92, 93 Medium-range radio system, 3842, 17273 Memory card, 148, 15860 Memory-only iButton, 16263 Memory usage iButton, 16264 MPEG decoder, 26869 smart card, 15253 MEO. See Medium-Earth orbit Messaging services, 123, 124, 137, 2023, 30710. See also Short message service MExE. See Mobile station application execution environment MGCF. See Media gateway control function MGW. See Media gateway Microbrowser, 201, 21113
429
Micro Digital Graphical MicroBrowser, 21213 Microprocessor-controlled smart card, 15253 Microprocessor usage, 19293, 36971 Microsoft Mobile Explorer, 212 Microsoft Stinger, 207, 21011 Microsoft Windows CE, 198, 199, 201, 202, 2067, 21011, 212, 276 Microsoft Windows for Smart Cards, 294 Microsoft Windows Media Audio, 26768 Microsoft Windows Media Encoder, 269 Microsoft Windows Media Video, 274 Middleware, 21315, 216, 27576 MIK. See Mobile Internet kit Mininotebook computer, 203 Mitsubishi Eclipse, 202 MMDS. See Multichannel multipoint distribution system MME. See Microsoft Mobile Explorer MMI. See Man-machine interface MMS. See Multimedia messaging services Mobile ad hoc network, 37374 Mobile agent, 129, 37980 Mobile Companion, 210 Mobile country code, 90 Mobile device addressing, 25960 Mobile electronic commerce, 137, 304, 32933 Mobile health care professional, 328 Mobile Internet, 16, 12628, 192 access technology, 2728, 3046 future developments, 38283 standardization, 24243 versus wireless Internet, 79 Mobile Internet kit, 208 Mobile Internet service provider, 130 Mobile messaging support, 214 Mobile multimedia terminal, 22021 Mobile network convergence, 3036 Mobile portal, 13240, 307 Mobile satellite service, 22, 8696 Mobile station application execution environment, 123, 221, 295 Mobile switching center, 74, 122 Mobile virtual network operator, 31718
430
UMTS and Mobile Computing
Mobility, 4 factors driving, 59 types, 12829 Mobility management, 8, 58, 104, 121, 12629 Modular mobile device, 220, 233 Molecular nanotechnology, 10 Moores Law, 2, 910, 36971 Motorola PDA Accompli, 202, 219 Moving Picture Experts Group, 265, 26674 Moving Picture Experts Group 1, 12, 265, 26668, 27374 Moving Picture Experts Group 2, 1112, 265, 26668, 274 Moving Picture Experts Group 4, 1112, 102, 144, 220, 265, 26971, 274, 347, 350 Moving Picture Experts Group 5 and 6, 271 Moving Picture Experts Group 7, 271 Moving Picture Experts Group 21, 27173 MP3, 11, 102, 144, 193, 202, 220, 268, 274, 332, 347, 350, 368 MP3 Pro, 268, 274 MP4, 267 MRP. See Market representation partner MSC. See Mobile switched center MSS. See Mobile satellite service Multiapplication smart-card operating system, 294 Multichannel multipoint distribution system, 31, 8081 Multimedia communication, 4 compression, 1112, 26364, 26674, 36869 developments, 1516, 25, 2930, 3003, 347, 379 portals, 13337 terminals, 22021 Multimedia messaging services, 123, 124, 2023, 30710 Multimode terminal, 12, 35, 77, 141 Multipath channel, 71 Multiprotocol label switching, 27 Multiservice networking, 4
MultOS. See Multiapplication smart-card operating system MVNO. See Mobile virtual network operator Naming service, 278 Narrowband code division multiple access, 71 Narrowband mobile satellite system, 9091 NAT. See Network address translation National Institute of Standards, 166 Neighborhood access, 303 Network address translation, 130, 253, 341, 343 Networked systems, 178 architecture, 37175 licensing, 2122 multimedia services, 3003 Networked vehicle intranet, 303 Network intelligence, 1 Network service layer, 256 Nippon Telephone and Telegraph, 71, 85, 132, 243, 284, 3067, 316, 318, 32022 NIST. See National Institute of Standards NMT. See Nordic Mobile Telephone Nokia Cardphone, 197 Nokia Communicator 9210, 202 Nokia WAP browser, 213 Nordic Mobile Telephone, 39, 55, 65, 68 North American digital cellular, 65 Notebook computer, 7, 146, 192, 196, 197, 203 NS layer. See Network service layer Object management architecture, 27677 Object Management Group, 27678 Object request broker, 27778 OCF. See OpenCard Framework OEM. See Original equipment manufacturer OFDM. See Orthogonal frequency division multiplex OMA. See Object management architecture OMG. See Object Management Group OmniTRACS, 94 OpenAir specification, 24849
Index OpenCard Framework, 29293 OpenCard Framework Group, 292 Open services gateway initiative, 188, 28283 Open standards, 33, 6869, 150, 153, 209 Operating system, 2, 198, 2058 Geoworks GEOS, 211 Linux Mobile, 211 Palm OS, 2089 Symbian EPOC, 20910 Windows, 21011 Operators perspective, 115 Optical memory card, 15960 Optimized time difference of arrival, 123 ORB. See Object request broker Organizer, 195, 198200 Original equipment manufacturer, 167 Orinoco, 6263 Orthogonal frequency division multiplex, 246 OS. See Operating system OSGI. See Open services gateway initiative OTDOA. See Optimized time difference of arrival P802.11 Working Group, 57 P802.15 Working Group, 5253, 245 P802.16 Working Group, 7980 Package delivery, 183 Packaging, application, 20 Packet Data Protocol, 105 Packet-switched domain, 121, 122, 125 Packet-switched network, 2527, 41, 103, 371 PAD. See Portable access device Paging services, 55, 91, 95, 198, 203 Palm OS, 19899, 207, 2089 PAMR. See Public-access mobile radio PAN. See Personal area network Passive backspatter frequency identification tag, 173, 231 Payment services, 333, 377 PCF. See Point coordination function PCG. See Project Coordination Group PCMCIA. See Personal Computer Memory Card International Association PCS. See Personal communications service
431
PDA. See Personal digital assistant PDC. See Personal digital cellular PDP. See Plasma display panel Peer-to-peer communication, 5, 57, 98 Pen-only personal digital assistant, 19899 Pen tablet, 203, 234 Pentium processor, 10 Performance factor bit rate, 115 Performance factor traffic capacity, 11719 Personal area network standard, 24546, 336 Personal communication service, 6465, 7778, 83, 85 Personal communication service 1900, 88 Personal computer, 192, 194, 368 Personal Computer Memory Card International Association, 7 Personal Computer/Smart Card Working Group, 292 Personal digital assistant, 6, 7, 43, 47, 57, 139, 146, 192, 193, 194, 195, 196, 197, 19899, 226, 234, 306, 368 Personal digital cellular, 40, 69, 70, 90, 101, 286, 320 Personal Handy Phone System, 2021, 250, 313 Personal identification number, 149, 165, 332 Personal information manager, 197, 226 Personalization, 45, 8, 16, 2728, 128, 133, 134, 13637, 140, 144, 300, 3067, 316 PersonalJava, 13 Pervasive computing, 191, 22730 Photography-image encoding, 26566 PHS. See Personal Handy Phone System Physical layer, 24748 PIM. See Personal information manager PIN. See Personal identification number Plant maintenance, 22829 Plasma display panel, 10 PLMN. See Public land mobile network Plug and play, 254, 275, 371 PML. See Procedural markup language PMR. See Private mobile radio Point coordination function, 60
432
UMTS and Mobile Computing
Point of presence, 129 Point-of-sale scanning, 169 Point-to-point connection, 58 PoP. See Point of presence Portability, UMTS, 31618 Portable access device, 204, 226 Portable data capture system, 178 Portals, 13240, 307 PoS. See Point-of-sale scanning Positioning systems, 8, 178 Privacy, 194, 335 Private mobile radio, 22, 78 Procedural markup language, 287 Product identification, 179, 181 Production applications, 184 Productivity, employee, 33 Project Coordination Group, 251 PSTN. See Public switched telephone network Public-access mobile radio, 79 Public land mobile network, 74, 90 Public switched telephone network, 21, 56, 74, 86, 201, 26364 QCIF. See Quarter common intermediate format QoS. See Quality of service QPSK. See Quadrature phase shift keying Quadrature phase shift keying, 117 Quality of service, 27, 68, 102, 119, 136, 256, 272 Quarter common intermediate format, 270 Quicktime, 274 RACE. See Research and Development in Advanced Communications for Europe Radar Smart Tag, 186 Radio frequency, 3738 Radio frequency identification, 17081, 227, 23132 Radio frequency identification tag, 17273, 18587 Radio local area network, 22 Radio network controller, 119 Radio system capacity, 35053 RAM. See Random-access memory
Random-access memory, 208 RangeLAN, 63 RDF. See Resource description framework Reader/interrogator, 176 Read-only memory, 15253 Real Audio 8, 26768 Real-time application, 2068, 315 Real-time software download, 13 Real-Time Specification for Java, 217, 219 Real Video, 274 Reconfigurable terminal, 14243 Registration standards, 25859 Relational markup language, 383 Remote collaboration, 302 Remote method invocation, 213, 215, 275, 276, 279 Remote procedure call, 278 Remote reference layer, 279 Research and Development in Advanced Communications for Europe, 82 Resource description framework, 382 Retail applications, 184 RF. See Radio frequency RFID. See Radio frequency identification RLAN. See Radio local area network RMI. See Remote method invocation RML. See Relational markup language RNC. See Radio network controller Roaming, 17, 18, 27, 33, 57, 67, 72, 73, 75, 81, 88, 89, 98, 99, 1078, 109, 130, 131, 248, 254, 263, 311 ROM. See Read-only memory Routing, 254, 256 RPC. See Remote procedure call RTSJ. See Real-Time Specification for Java Sales applications, 228 SAT. See SIM Application Toolkit Satellite personal communications network, 8890 Satellite network, 22, 42, 120 location-based services, 31314 global positioning system, 9495 IMT-2000, 8586 mobile communications, 8690 technology, 9094
Index SAT-PCN. See Satellite personal communications network SBC. See Single board computer Scalability, 153, 194, 209 SCSL. See Sun Community Source License SDMA. See Space division multiple access SDMI. See Secure digital music initiative SDO. See Standardization development organization SDR. See Software-defined radio Second-generation mobile network, 4, 7, 1819, 39, 4142, 72, 81, 99, 115, 26364 Secure digital music initiative, 268 Secure socket layer, 139, 212 Security, 8, 121, 329 iButton, 162, 16467 Internet, 151, 25455 intranet, 2930 mobile computing, 13940, 19394, 268 smart card/tag, 153, 15657, 15960, 162, 183 Self-provided mobile network, 22 Service, definition of, 304 Service applications, 228, 368, 37879 Service broker, 317 Service communities, 372 Service differentiation, 131 Service enablers, 16, 12324 Service gateway, 28283 Service mobility, 129 Service plane, 10910 Service provider, 317, 341 Serving GPRS support node, 76, 105, 256 Session Initiation Protocol, 123, 144, 258 SGML. See Standardized general markup language SGSN. See Serving GPRS support node Shannon formula, 66 Shared Wireless Access Protocol, 5152 Sharp Messenger 500, 201 Short message service, 17, 18, 73, 92, 102, 193, 202, 208, 22324, 3079, 323, 332, 376 Short-range radio system, 3840, 42, 369 Siemens SL45, 219
433
Siemens Smart Handheld, 2012 Signaling and control plane, 10810 SIM. See Subscriber identity module SIM Application Toolkit, 131, 22224, 29495 Simple Mail Transfer Protocol, 23, 25, 134, 138, 256, 275 Simple Object Access Protocol, 129, 213, 275, 276, 372 Simultaneous voice call/data transfer, 76 Single board computer, 204 SIP. See Session Initiation Protocol Situated computing, 379 Small information appliance, 14547, 230 Small PC Rugged Computers for Small Spaces, 204 Smart antenna, 1314, 65, 124, 351 Smart badge, 327 Smart car, 32425 Smart card, 14445, 148, 15058, 16567, 22225, 23031, 29195, 325, 329, 332, 377 Smart cargo, 32526 Smart device, 205, 22530 Smart handheld, 2003 Smart interconnected home appliance, 18892 Smart key, 18788 Smart label, 181 Smart pager, 203 Smart phone, 7, 139, 193, 196, 197, 198, 2003, 219, 233, 234 Smart portable device, 22526 Smart tag, 18187, 23233, 327 Smart terminal, 131 Smart truck, 32425 SMIL. See Synchronized multimedia integration language SMS. See Short message service SMTP. See Simple Mail Transfer Protocol SNDCP. See Subnetwork Dependent Convergence Protocol Sniffing, 68 SOAP. See Simple Object Access Protocol Soft handover, 119 Soft real-time application, 206 Software-defined radio, 1214
434
UMTS and Mobile Computing
Space division multiple access, 14 Spatial filter, 14 Special data capture device, 203 Special-feature iButton, 16364 Specification Release 3, 104 Spectral efficiency, 11719, 345 Spectrum allocation. See Frequency spectrum Spreading code, 110 Spread spectrum, 58, 59, 66, 70, 248 SRAM. See Static random access memory SSL. See Secure socket layer Standard generalized markup language, 28485 Standardization addressing and registration, 25863 broadband wireless, 34, 7980 computer languages, 28491 GSM, 7274 IMT-2000, 8182, 110, 123 information encoding, 26374 mobile portal, 13839 overview, 33, 3940, 24144, 366, 375, 38081 PAN and LAN, 24350 radio frequency identification, 181 smart card, 29195 software and protocols, 27484 third-generation, 25053 time division multiple access, 6970 Standardization development organization, 250, 25152 Static random access memory, 166 Stinger, 198 Streaming media sector, 26465 Stub program layer, 279 Subnetwork Dependent Convergence Protocol, 256 Subnotebook computer, 203 Subscriber identity module, 58, 73, 128, 143, 14445, 219, 22224, 279, 291, 294, 332 Sun Community Source License, 280 Super-small mobile technology, 195, 197 Support node, 76, 105, 122, 12627 SWAP. See Shared Wireless Access Protocol
Symbian EPOC, 207, 20910 Symbian microbrowser, 212 Synchronized multimedia integration language, 285, 382 T1 Committee, 82, 250 TACS. See Total access communications system Tag technologies, 16892, 23133, 327 Tangible capabilities, 18788 TCP/IP. See Transmission Control Protocol/Internet Protocol TD/CDMA, 72, 110 TDD. See Time division duplex TDMA. See Time division multiple access TDOA. See Time difference of arrival TD/SCDMA, 65, 72, 84, 104, 116, 122 Technical Specification Group, 25152 Technology enablers, 13 Technology positioning, 98100 Telecommunications Industry Association, 65, 68, 6970, 242 Telecommunications Technology Association, 82, 242, 250 Telecommunications Technology Committee Korea, 72, 82 Teleconferencing, 269 Teledesic, 87, 90 Telemedicine, 301 Telemetry, 32229 Terminals dual-mode, 8890, 1078 market development, 7, 3536 mobile, 128, 178, 2001, 203, 22021 operating system, 2056 UMTS, 14144, 265 Terrestrial network, 8890, 31415 TETRA. See Trans European trunked radio TETRAPOL, 22, 40, 79 Text messaging, 17 Thin client, 372 Third-generation mobile device, 192234 basic architecture, 21920 mobile multimedia terminal, 22022 smart cards, 22225 summary, 23334
Index Third-generation mobile network, 4, 8, 33, 36, 40, 42, 6768, 72, 81, 99, 115, 129, 302 media encoding, 27374 standardization, 25058 Third Generation Partnership Project, 72, 8182, 84, 1036, 119, 121, 123, 242, 243, 25052 Third Generation Partnership Project 2, 82, 84, 250 Third-generation portal, 13940 Third-generation terminal, 14344 Thuraya Satellite Telecommunications Company, 9394 TIA. See Telecommunications Industry Association Ticketing services, 333 TIME. See Time interactive multimedia extension Time difference of arrival, 313, 314 Time division duplex, 67, 72, 104, 111, 11214, 11619, 350 Time division multiple access, 39, 45, 56, 6370, 73, 351, 368 Time interactive multimedia extension, 382 Time of arrival, 314 TINI. See Tiny Internet interface Tiny Internet interface, 204 TLD. See Top-level domain name TLS. See Transport layer security TOA. See Time of arrival Token ring network, 60 Tool management, 180 Top-level domain name, 337, 340, 344 Total access communications system, 39, 55, 65, 68 Traffic asymmetry, 34647, 348, 352 Traffic capacity, 11415, 11719, 345, 34753, 382 Traffic channel reuse, 14 Transaction management, 33031 Transceiver, 17172 Trans European trunked radio, 22, 4041, 7879 Transmission Control Protocol, 126, 127, 256, 274, 319
435
Transmission Control Protocol/Internet Protocol, 52, 58, 216 Transparency, 2, 8, 62, 101 Transponder, 17172, 178, 186 Transportation applications, 17879, 18384, 32526 Transport connection layer, 279 Transport control, 125 Transport layer security, 139 Travel applications, 229 True time clock, 16667 Trunked radio technology, 22, 4041, 7879 TSG. See Technical Specification Group TTA. See Telecommunications Technology Association TTC. See Telecommunications Technology Committee Korea Tunneling, 12930, 258, 3046 Two-dimensional bar code, 169 Two-way paging, 95, 203 Ubiquitous computing, 25, 86 application potential, 299303 developments towards, 1730, 36569 market convergence, 3036 meaning of, 147, 194 Ubiquitous computing browser, 213 Ubiquity, 2 UC. See Ubiquitous computing UDD. See Unconstrained delay data UDP. See User Datagram Protocol UICC. See Universal IC card ULR. See Uniform resource locator Ultra high frequency, 78, 83 Ultra wideband, 369, 370 UMS. See Unified messaging services UMTS. See Universal Mobile Telecommunication System UMTS Forum, 82, 88, 100, 106, 195, 243, 251, 304, 310, 311, 313, 315, 347, 348, 353, 354, 355, 356, 359, 378 Unconstrained delay data, 11819 Unified messaging services, 309 Uniform resource locator, 132, 205, 258, 288, 340
436
UMTS and Mobile Computing
Uniform resource name, 340 Universal access, 1112 Universal device, 188 Universal IC card, 153, 22024, 279 Universal Mobile Telecommunication System, 15, 18, 3132, 32, 35, 36, 40, 42, 58, 70, 342 importance, 8183 information-based services, 1035 ISP function, 12932 portals, 13241 radio access, 11020 satellite component, 8586 services and applications, 14445, 30418 spectrum allocation, 99, 35359 standardization, 24243, 250, 25253, 25658 technology overview, 8385, 99, 1003, 10510, 12029, 14142 terminals, 14144, 22022, 265 Universal Mobile Telecommunication System Release 3, 105, 130 Universal Mobile Telecommunication System Release 4, 104, 105, 12223, 127, 130, 25556 Universal Mobile Telecommunication System Release 5, 105, 109, 12324, 12728, 130, 252, 25558 Universal Mobile Telecommunication System Release 6, 124 Universal Mobile Telecommunication System Release 7, 12425 Universal Mobile Telecommunication System Release 99, 104, 106, 109, 12122, 127, 252, 25556 Universal personal telecommunications number, 336 Universal Plug and Play, 188, 276, 28283 Universal product code, 169 Universal serial bus, 283 Universal subscriber identity module, 1067, 123, 124, 128, 131, 14445, 219, 22224, 261, 279, 291, 294300
Universal subscriber identity module card reader, 22022 Universal terrestrial radio access, 49, 8485, 111, 119, 141 Universal terrestrial radio access network, 1045, 107, 11920, 12324 Universal wireless communication, 8485 Universal Wireless Communication Consortium, 69, 243 UP Browser, 212 UPC. See Universal product code UPnP. See Universal Plug and Play UPTN. See Universal personal telecommunications number URN. See Uniform resource name USAT. See USIM Application Toolkit USB. See Universal serial bus U.S. Department of Defense, 177 User Datagram Protocol, 127, 129, 256 User identification, 377 User mobility, 128 User-oriented portal, 133 Users perspective, 114 User virtual environment, 129 USIM. See Universal subscriber identity module USIM Application Toolkit, 22224, 29495 U.S. Intelligent Transportation System, 177 U.S. Wireless Communication Consortium, 251 UTRA. See Universal terrestrial radio access UTRAN. See Universal terrestrial radio access network UWB. See Ultra wideband UWC. See Universal wireless communication UWCC. See Universal Wireless Communication Consortium Value chain, 1035 Vehicle applications, 17880, 18284, 186, 199, 3013, 32426, 374 Vertical market facilities, 277 Very high frequency, 78
Index VHE. See Virtual home environment Video communication. See Compression standards; Multimedia communication Videoconferencing, 273, 274, 31516 Video support services, 137 Videotelephony, 31516 Virtual conferencing, 376 Virtual connection, 26, 103, 108, 255 Virtual home environment, 4, 129, 136, 295, 31617 Virtual navigation, 301 Virtual private network, 306 Virtual resource management, 129 Virtual team, 36, 19091 Visitor location register, 75, 126 VLR. See Visitor location register Voice communications, 17, 27, 41, 68, 137, 31516, 372 Voice encoding, 265 Voice extensible markup language, 28788 Voice-machine interface, 10 Voice over Internet Protocol, 27, 123, 258, 315 Voice recognition, 10, 220, 376 Voice XML. See Voice extensible markup language VoiceXML Forum, 287 VoIP. See Voice over Internet Protocol VoxML, 138 VPN. See Virtual private network W3C. See World Wide Web Consortium WAN. See Wide area network WAP. See Wireless Application Protocol WAP Forum, 242, 290, 319 WARC. See World Administrative Radio Conference Warehouse applications, 229 Wave division multiplexing, 80 WBMP. See Wireless bitmap WCDMA. See Wideband code division multiple access WCML. See Web composition markup language Wearable electronics, 230, 37576, 382 Web composition markup language, 285
437
Web Watch, 204 WECA. See Wireless Ethernet Compatibility Alliance Wide area network, 23, 6386 Wideband code division multiple access, 6, 71, 72, 101, 11014, 250, 318 Wideband radio interface, 381 Wireless Application Protocol, 1819, 20, 73, 75, 101, 131, 201, 202, 208, 210, 212, 21415, 221, 224, 276, 286, 28991, 313, 31820, 332, 343 Wireless bitmap, 265 Wireless bridge, 58 Wireless communication, 3742 Wireless Ethernet Compatibility Alliance, 246 Wireless information device, 209 Wireless Internet, 79, 3031 Wireless LAN Interoperability Forum, 63, 24849 Wireless local area network, 2122, 3435, 3839, 43, 375 addressing, 26263, 339 health care applications, 32629 spectrum issues, 99100, 35963 standardization, 24649 technology, 5663, 98 Wireless local loop, 249 Wireless markup language, 20, 135, 138, 140, 144, 212, 217, 28587, 289, 318 Wireless mobile access to Internet, 1718 Wireless personal area network, 4356, 5253, 98 addressing, 26162 spectrum allocation, 99100 Wireless personal area network (continued) standardization, 24546 Wireless Session Protocol, 214 Wireless terrestrial cellular technology, 1819 Wireless transport layer security, 139 Wireless wide area network, 6386 WLAN. See Wireless local area network
438
UMTS and Mobile Computing
WLIF. See Wireless LAN Interoperability Forum WLL. See Wireless local loop WML. See Wireless markup language Workforce patterns, 7 World Administrative Radio Conference, 90, 95 World Radio Conference, 35658 World Wide Web, 7, 2829, 192, 28489, 370 World Wide Web appliance, 205 World Wide Web Consortium, 242, 285, 291, 382 WORM. See Write-once-read-many
WPAN. See Wireless personal area network WRC. See World Radio Conference Write-once-read-many, 159 WSP. See Wireless Session Protocol WTLS. See Wireless transport layer security WWW. See World Wide Web X-10, 280 XHTML. See Extensible hypertext markup language XML. See Extensible markup language XSL. See Extensible stylesheet language Zeroization, 166