Enabling Technologies for Wireless E-Business phần 1 doc

The rapid growth in the number of wireless subscribers along with the emergence of new wireless technologies such as 3Gand Wi-Fi, allowing for higher transmission rates will lead to an e

Weidong Kou

Yelena Yesha (Eds.)

With 141 Figures and 15 Tables

Technologies for Wireless E-Business Enabling

c

Weidong Kou

Chinese State Key Laboratory of ISN

2 South Taibai Road

This work is subject to copyright All rights are reserved, whether the whole or part of the material

is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, casting, reproduction on microfilm or in any other way, and storage in data banks Duplication of this publication or parts thereof is permitted only under the provisions of the German Copyright Law of September 9, 1965, in its current version, and permission for use must always be obtained from Springer, Violations are liable for prosecution under the German Copyright Law.

broad-Springer is a part of broad-Springer Science+Business Media

springer.com

Springer-Verlag Berlin Heidelberg 2006

Printed in The Netherlands

The use of general descriptive names, registered names, trademarks, etc in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use.

Cover design: KünkelLopka, Heidelberg

Printed on acid-free paper 45/ 3100/ SPI 5 4 3 2 1 0

ACM Classification: C.2, C.3, H.4, J.1

Typesetting: SPI Publisher Services using Springer Word makropackage

3-540-30449-5 Springer Berlin Heidelberg New York

978-3-540-30449-4 Springer Berlin Heidelberg New York

SPIN: 10959497 kou_weidong@yahoo.com.cn

y The Ministry of Information Industry of China reported that at the end

of 2005, the number of mobile subscribers in the country was close to

400 millions It is predicted that by the end of 2006, the number of mobile subscribers in China can reach 440 millions In addition, thenumber of short messages sent in China in 2005 was over 300 billions,and the associated revenue was close to $4 billion US dollars

y According to LaNetro Zed based in Madrid of Spain, at the end of

2005, West Europe has over 270 millions of wireless subscribers Germany is the largest market for mobile phones in Europe, with 74.1million users, and it has a penetration rate of 90%; Italy is the second largest market in Europe, with over 65.3 million mobile subscribers and a penetration rate of 114%, the highest in the world; the United Kingdom has 64 million subscribers and a mobile phone penetration rate of 106%; the penetration rate in Finland stands at 100% withnearly 5.2 million subscribers

y In 2005 total number of mobile service subscribers in Russia has grown by 70 percent and reached 125.8 million, according to a recent report in 2006 from AC&M consulting bureau

y According to Mobile Marketing Association, in the United States the number of wireless subscribers was over 200 millions The data on the Mobilephonediscuss.com Forums shows that 66% of US households own cell phones

y In Canada, with the number of subscribers to wireless products and service totaling close to 13.9 million by mid-2004, almost 43% of Canadians now have access to a wireless device By the end of 2005,

it was estimated that this number is probably over 50%

y Global wireless service revenue is expected to rise 11% to $623.9billion The global wireless service industry is expected to generate

$800 billion in revenue in 2010, with emerging markets accounting for about 42% of the total

y Worldwide shipments of mobile phones reached a record 242 million units in Q4 2005, surpassing the previous peak of 200 million units in Q4 2004, according to iSuppli For all of 2005, 813 million units wereshipped, up 14% from 713 million in 2004.

The list of statistics can go on and on The rapid growth in the number of wireless subscribers along with the emergence of new wireless technologies such as 3Gand Wi-Fi, allowing for higher transmission rates will lead to an explosion of new e-business applications and services generally referred to as “wireless e-business” yWireless e-business allows people to conduct business wirelessly without physicalconnectivity A variety of different devices can be used for wireless e-business,including mobile phones, pagers, palm-powered personal computers (PCs), pocket PCs, laptop computers, and other mobile devices or devices connected to the wireless networks

Because wireless e-business holds the promise to reshape the way businessesconducted, and because it has a huge customer base, the advantages of wirelesse-business are endless The key is that people can break free from spatial and temporal constraints and communicate and transact in business anytime and anywhere However, there are a number of great challenges, including problems of sustaining connectivity, limited resources such as limited bandwidth and limited frequency spectrum, as well as the issues of security and privacy in a wirelessenvironment To address these problems and issues, huge efforts have been made

to develop a variety of enabling technologies, including new wireless cation technologies, wireless security, wireless application protocols, mobile payment protocols, mobile data management, mobile agents, mobile payment, mobile computing, mobile services, and RFID technologies Drs Weidong Kouand Yelena Yesha have edited this book, with assistance from the chapter contributors to cover these technologies

communi-I believe this is an excellent book for business managers, e-business developers, academic researchers, university students, professors, and professional consultants

to acquire comprehensive knowledge on enabling technologies for the bloomingwireless e-business I highly recommend this book!

Robert MayberryVice President, Sensors and Actuators

IBM Software Group

Table of Contents

1 Introduction to Enabling Technologies for Wireless E-Business

W Kou and Y Yesha 1

1.1 Introduction 1

1.2 About This Book 3

References 5

2 Fundamentals of Wireless Communications D Shen and V.O.K Li 7

2.1 Introduction 7

2.2 Global System for Mobile Communication 7

2.3 General Packet Radio Service 15

2.4 Code Division Multiple Access Systems 22

2.5 Summary 41

References 41

3 Wireless Security 44 3.1 Introduction 44

3.2 Mobile Certificate 46

3.3 Elliptic Curve Cryptography for Mobile Computing 51

3.4 Server Assisted Mobile Security Infrastructure 62

3.5 Summary 72

References 73

4 Wireless Application Protocol W Kou 76

4.1 Introduction 76

4.2 Wireless Application Protocol 76

4.3 Wireless Application Security 85

4.4 Summary 86

4.5 Appendix 86

References 87

W -B Lee

5 RFID Technologies and Applications

D Kou, K Zhao, Y Tao and W Kou 89

5.1 Introduction 89

5.2 Components 92

5.3 Middleware Technology 99

5.4 Standards 102

5.5 Summary 107

References 108

6 Software Infrastructure for Context-Aware Mobile Computing C.L Wang, X.L Zhang, N Belaramani, P.L Siu, Y Chow, and F.C.M Lau 109

6.1 Introduction 109

6.2 Context-aware Mobile Computing Infrastructure 111

6.3 A Case Study – The Sparkle Project 115

6.4 Summary 128

References 129

7 Data Management for Mobile Ad-Hoc Networks F Perich, A Joshi, and R Chirkova 132

7.1 Introduction 132

7.2 Origins of Mobile Peer-to-Peer Computing Model 133

7.3 Challenges 135

7.4 Peer-to-Peer Data Management Model 156

7.5 Future Work 169

7.6 Summary 170

References 171

8 Mobile Agents: The State of the Art B Yang and J Liu 177

8.1 Introduction 177

8.2 System Facilities 178

8.3 Migration and Planning 180

8.4 Communication and Interoperability 184

8.5 Security 190

8.6 Summary 194

References 197

Table of Contents

9 Multiagent Communication for e-Business using Tuple Spaces

H.F Li, T Radhakrishnan, and Y Zhang 199

9.1 Introduction 199

9.2 Computation and Tuple Spaces 200

9.3 Examples of Agent Coordination in e-Commerce 204

9.4 A Tuple Space Based Framework for Agent Communication 207

9.5 A Case Study in e-Commerce Using Tuple Spaces 217

9.6 Summary 230

References 231

10 Mobile Payment Y Liu, X Cao, and L Dang 233

10.1 Introduction 233

10.2 Characteristics 233

10.3 Agents 236

10.4 Security for Mobile Payment 244

10.5 Summary 251

References 252

11 Mobile Content Delivery Technologies Y Yang, and R Yan 253

11.1 Introduction 253

11.2 Short Message Service 253

11.3 Multimedia Messaging Service 262

11.4 Transcoding Techniques 275

11.5 Summary 292

References 292

12 Mobile Services Computing L Zhang, B Li, and Y Song 299

12.1 Web Services Overview 299

12.2 Extending Web Services to Mobile Services 299

12.3 General Architecture of Mobile Services 303

12.4 Two General Approaches to Develop Web/Mobile Services 306

12.5 Case Study – WAS (Wireless Alarm System) 306

12.6 Summary 309

References 310

IX

13 Location-Aware Services and its Infrastructure Support

Y Chen and D Liu 312

13.1 Introduction 312

13.2 Location Operating Reference Model and Infrastructure 313

13.3 Location Server 317

13.4 Moving Object Databases 322

13.5 Spatial Publish/Subscribe Engine 326

13.6 Related Works 330

13.7 Summary 332

References 332

14 Mobile Commerce and Wireless E-Business Applications S Song 335

14.1 Introduction 335

14.2 Mobile Commerce 336

14.3 Wireless e-Business Applications 344

14.4 Case Study 354

14.5 Summary 359

References 359

Glossary 361

About the Editors 371

Contributors 373

, Index 379

1 Introduction to Enabling Technologies for Wireless E-Business

Advancements in wireless technologies hold the promise to reshape the way businesses conducted With wireless technologies, people can break free from spa-tial and temporal constraints, as they are able to use these technologies to work anywhere and anytime With wireless e-business, companies can locate inventory items, anytime, anywhere; emergency units are able to respond in real time; and universities are able to manage communications across campuses The rapid growth in mobile telephony in recent years has provided a strong model for theadoption of undeterred wireless e-business A number of consulting firms havemade various estimations on the growth of the number of mobile phone usersworldwide These estimations are certainly confirmed by the huge increase in the number of mobile phone users in China – the country currently has over 300 mil-lion mobile phone users, more than the entire population of the USA The rapid transition from fixed to mobile telephony will almost certainly be followed by a similar transition from conducting e-business through desktop computers via physical connectivity to wireless e-business through a variety of mobile devices via wireless communication networks in the near future

To make wireless e-business work effectively, a variety of enabling gies are needed First, one must be connected wirelessly This means that wireless communications networks must be in place From the first commercial GlobalSystem for Mobile Communication (GSM) network launched in 1992 to 3G ser-ttvices launched in Hong Kong, UK, and Italy in recent years, wireless communica-tion networks have penetrated almost every part of the world The 2G/2.5G and 3G wireless communication systems are the cornerstones of wireless communica-tions In addition, there are other wireless networks, such as Wi-Fi, Wi-Max,Bluetooth, and infrared Wireless security is crucial for wireless e-business Ac-cessing the Internet, digitally signing e-commerce transactions, authentication, and

technolo-W Kou and Y Yasha*

ISN National Key Laboratory, Xidian University, Xi’an, China

encryption of transaction information, all these wireless e-business activities need security However, given that wireless e-businesses broadly use mobile devicessuch as mobile phones, and that these devices have strict processing requirements and storage limitations of wireless environments, ubiquitous wireless security technologies must be ready to satisfy these requirements and overcome these limi-tations To enable mobile Internet applications, application environment and vari-ous application protocols are needed In 1997, Ericsson, Motorola, and Nokia formed a forum for creating such protocols As a result, the wireless applicationprotocol (WAP), a suite of emerging standards, has been defined The WAP is de-signed to assist the convergence of two fast-growing network technologies, namely, wireless communications and the Internet The convergence is based on the rapidly increasing numbers of mobile phone users and the dramatic effect of e-business over the Internet The combination of these two technologies will have a big impact on current e-business practice, and it will create huge market potential

To be able to connect mobile people to the information and applications they need — anytime and anywhere, to allow people to have computation capabilitiesand network resources at hand, and to move the workplace to any place, support-ing the broadest spectrum of mobile networks and a wide array of devices on the client side, necessary wireless middleware software and mobile data management are essential When a mobile user moves with a handheld mobile device and con-nects to a wireless network, how one can ensure that the connection will not be lost while the user moves out of the range of the wireless network that can reach? Roaming from one wireless network into another is therefore a desired feature for wireless e-business applications

Mobile content delivery technology deals with delivering the digital contents to mobile devices with limited computing and storage resources For example, if a digital photo is too large to fit into the memory of a mobile phone, then for the mobile user to see the photo, one must convert the original digital photo into one

of a smaller size that can fit into the mobile phone This converting process is called transcoding

When a mobile user is located in a place where the businesses are close to him, these businesses may wish to inform the user on either services or products avail-able at a special price, which the user might be interested in The technology ena-bling such a capability is called location-aware technology, while related servicesare called location-aware services

To transact wireless e-business, mobile payment is essential Without mobilepayment, wireless e-business is not going to be successful as people need to col-lect the payment when they conduct e-business anytime and anywhere Mobilepayment needs wireless security to ensure secure authentication and data confi-dentiality In addition, restriction of mobile devices and wireless communicationsmust be considered while making the payment

Wireless e-business also needs mobile agent technology A mobile agent system

is a platform that can create, interpret, execute, transfer, and manage agents Theability to travel, which distinguishes mobile agents from other types of agents, al-lows them to move to a new host and then to take advantage of being in the same environment to interact with each other locally

1 Introduction to Enabling Technologies for Wireless E-Business 3Mobile Web service is an extension of Web service technology A Web service

is a software system designed to support interoperable machine-to-machine action over a network It is a standard computing unit over the Internet There are three technologies to make Web service work, namely, Web Services Description Language (WSDL), Simple Object Access Protocol (SOAP), and Universal De-scription, Discovery, and Integration (UDDI) With WSDL, a legacy system can

inter-be wrapped with a standard interface and inter-becomes a Web service SOAP, on the other hand, provides a standard connection among those Web services so that communications among them can be carried out UDDI is a registration server, which is available for the convenience of publishing and retrieving Web services.According to the information in UDDI servers, consumers of Web services areable to obtain essential knowledge so as to ensure that the services meet their re-quirements Mobile Web service extends Web service with considerations of mo-bility, wireless security, restriction of mobile devices, and multimodality

Radio Frequency Identification (RFID) is a not-quite-new wireless technology that has a wide range of applications from automatically collecting highway tolls, identifying and tracing products and managing supply chain, to controlling access

to buildings and offices A minimum RFID system consists of an RIFD tag, anRFID reader, and a computer host Each RFID tag holds a microchip surrounded

by a printed antenna and protected between laminates, which can be pasted to a product The chip on the RFID tag holds data in its memory that can identify a manufacturer, a particular product model, and an individual product An RFID reader is a device to read the tag at a distance Radio waves from the reader hit the tag with enough power for the tag to retransmit the data back to the reader Thehost computer processes the data and passes them to business applications

Given a number of market demands and needs, including societal shifts toward

a more mobile workforce, geographical mobility among corporate individuals,criticality of time and effective decision making within narrow windows of oppor-tunities, increasing need for remote communication, computing and collaboration,increasing availability of wireless connections at affordable rates, new and impor-tant requirements for mobile computing support such as intelligent mobile agents, and mobile knowledge networking, particularly, given a close to one billion mo-bile phone users (if not yet exceeded), which is a huge potential customer base for wireless e-business, we can certainly say that wireless e-business is very promis-ing and will have a very bright future

1.2 About This Book

As doing e-business wirelessly is becoming a new trend and as there is a huge demand from business executives and managers, technological practitioners, stu-dents, and teachers who wish to know how e-business can be done wirelessly, and what the technologies to support wireless e-business are, this book is a response tothis demand by providing readers with comprehensive information on enabling technology for wireless e-business The target audience of this book includese-business developers, business managers, academic researchers, university

students, professors, and professional consultants This book can also be used for e-business classes and training courses

We have invited leading experts in various countries and regions, includingUSA, Canada, Hong Kong, Taiwan, and China, to contribute to this book From wireless communication fundamentals to wireless applications, the book coversthe major subjects related to enabling technologies for wireless e-business, includ-ing wireless security, mobile agents, mobile payment, mobile computing, mobiledata management, location-based services, software infrastructure, wireless appli-rrcation protocol, and RFID technologies

Chapter 2 presents a brief introduction of the fundamentals of wireless nications, including a variety of cellular standards, such as GSM, GPRS, IS-95, cdma2000, and UMTS

commu-Chapter 3 deals with mobile security issues with the intrinsic restrictions that are inherent in the mobile devices and the wireless environment, and possiblepractical solutions that can be used to overcome those restrictions, including thewireless equivalent of public key cryptosystem and elliptic curve cryptography, analternate approach to conventional public key cryptography, which is suitable for applications under resource-constrained conditions

WAP is a suite of emerging standards to enable mobile Internet applications The WAP standards have been created as a result of the WAP Forum that wasformed in June 1997 by Ericsson, Motorola, and Nokia The WAP Forum is de-signed to assist the convergence of two fast-growing network technologies,namely, wireless communications and the Internet Chapter 4 presents a detailed introduction to WAP, including the application environment and various proto-cols

Chapter 5 focuses on a very hot wireless technology, RFID, which has a huge potential in managing products and people, particularly in the areas of supplychain management, manufacturing, asset management, product tracing, and secu-rity access control

An extended form of mobile computing, namely, context-aware mobile ing, is investigated, and the issues in building software infrastructure for support-tting this paradigm are discussed in Chap 6

comput-Chapter 7 presents an overview of challenges arising in the area of mobile data management and surveys existing solutions, with emphasis on data management

in mobile ad hoc networks Various challenges related to data management in bile ad hoc networks, information discovery in dynamic networks, and traditionaldata management issues, such as transactional support or consistency among data objects, are discussed, and possible solutions to these challenges are proposed.The topic of mobile agents is the focus of Chap 8 After a brief introduction of the concept of mobile agents, the chapter outlines the advantages and applications

mo-of mobile agents, and presents important technologies for implementing mobileagent systems

Chapter 9 extends the discussions of mobile agents, by presenting how the ordination and information sharing among multiple agents can be done through the tuple space-based coordination model

co-Mobile payment is crucial to wireless e-business, simply because without lecting payment instantly regardless of where users are, the wireless e-businesscannot survive Chapter 10 presents a variety of mobile payment technologies f

col-Chapter 11 deals with mobile content delivery technologies, including ing services technologies, such as short message service (SMS) and multimedia message service (MMS), and existing transcoding technologies of image, video, audio, and Web pages

messag-Web service is an effective technique for improving business efficiency by automating the collaboration of heterogeneous information systems By extending

it to the wireless and mobile world, many more people can be connected to the enor-aamous Web of information and services, anywhere and anytime Chapter 12 presents mobile services, which is the next direction of Web service

Chapter 13 presents the Location Operating REference (LORE) model, ing domains of location operation semantic, privacy and security, management and location-aware agent To support the rich sets of location-aware wireless ap-plications, based on the LORE model, an infrastructure – Location-Based Servicesn(LBS) middleware—can be built, which has three key components: locationserver, moving object database, and spatial pub/sub engine

includ-The book concludes with Chap 14, in which mobile commerce, horizontal wireless e-business applications, and vertical wireless e-business applications areidentified and presented with case studies

The readers can use the structure of the book effectively If they have no ground knowledge of wireless communications, they can then read chapters of this book sequentially; if they are already familiar with wireless communications, theycan skip reading Chap 2 Of course, the readers, if they wish, can always select a chapter without following a particular order

back-Acknowledgments

This work is supported in part by NSFC grant 90304008 from the Nature ScienceFoundation of China and the Doctoral Program Foundation grant 2004071001from the Ministry of Education of China

1 Introduction to Enabling Technologies for Wireless E-Business 5

1 W Kou, Y Yesha (eds.) (2000) Electronic Commerce Technology trends: Challenges and Opportunities IBM, Carlsbad

2 W Kou (1997) Networking Security and Standards Kluwer, Boston

3 W Kou, Y Yesha, C Tan (eds.) (2001) Electronic Commerce Technologies LNCS 2040 Springer, Berlin Heidelberg New York

4 M Sherif (2000) Protocols for Secure Electronic Commerce CRC, Boca Raton

5 M Shaw, R Blanning, T Strader, A Whinston (2000) Handbook on tronic Commerce Springer, Berlin Heidelberg New York

Elec-References

6 K Finkenzeller (2003): RFID-Handbook, “Fundamentals and Applications

in Contact less Smart Cards and Identification,” 2nd edition, Wiley, New York

7 J Ebersp cher, H Vögel, C Bettstetter (2001), GSM Switching, Services and Protocols, 2nd edition, Wiley, New York

8 T Halonen, J Romero, J Melero (2002), GSM, GPRS and EDGE ance, Wiley, New York

Perform-ä

2 Fundamentals of Wireless Communications

The University of Hong Kong, Pokfulam Road, Hong Kong

2.1 Introduction

Since the introduction of the first generation cellular networks in the 1980s, there nhas been tremendous growth in wireless communications In 1992 the first commercial GSM network was launched, which marked the beginning of era of digital cellular networks Since 2003, Hutchinson has latt aaunched 3G services in HongKong, UK, and Italy Today, wireless communication devices have penetrated almost every corner of the world and have become an indispensable part of our daily life In this chapter, we present a brief overview of 2G/2.5G and 3G wireless communication systems, with particular focus on security-related aspects rr

2.2 Global System for Mobile Communication

Global System for Mobile Communication (GSM), is currently the most widelymused wireless technology The number of global GSM customers is estimated to

be over 1 billion as of the first quarter of 2004, accounting for over 70% of the global market share

GSM was proposed in Europe (in fact, the initials were originally derived fromGroupe Special Mobile) and was under standardizationr by the European Telecommunication Standards Institute (ETSI) Currently, the work has largely been transferred to third generation partnership project (3GPP)

2.2.1 Overview

Currently, GSM operates in frequency bands of 400, 800, 900, 1,800, and 1,900 MHz A GSM channel has a bandwidth of 200 kHz The modulation scheme isfGaussian minimum shift keying (GMSK), which is a type of continuous 7-phasemodulation scheme Since GMSK has a constant amplitude envelope, it is desirable for simple amplifiers At the same time, it has a narrow power spectrum with lowadjacent channel interference The duplexing scheme is frequency division duplexing (FDD), with the uplink channel and downlink channels located in different frequency bands Since the uplink time slot is about three time slots later than the corresponding downlink slot, the mobile station (MS) does not have to send and receive at the same time, thus reducing system design complexity and cost

D Shen and V.O.K Li

transmitter, the voice is first digitized and source encoded Then channel coding(convolutional coding) and interleaving are applied for error correction To achieve confidentiality over the air interface, encryption is performed After modulation, the user signal is transmitted over the multipath fading channel At the receiver, the received signal is first demodulated, and then decrypted After deinterleaving and channel decoding, source decoding is conducted to restore the speech.

Fig 2 1 Processing of a voice call

9The multiple access scheme of GSM is time division multiple access (TDMA)with optional frequency hopping A TDMA frame lasts for 4.615 ms, and is divided into 8 time slots, corresponding to a slot time of 576.9µs The gross datarate of a frame is 271 kbps or 33.9 kbps for a slot This data rate is equivalent to156.25 bit periods in a time slot There are five types of time slot burst: normal,

we show the structure of a normal burst In a normal burst, the first three bits are tail bits The next 57 bits are data bits, followed by 1 signaling bit, 26 training bits,

1 signaling bit, 57 data bits, 3 tail bits, and finally a guard period of 8.25 bits

Fig 2 2 Structure of a normal time slot burst

The TDMA frames are further organized into multiframes There are twotypes of multiframes: one type consists of 26 TDMA frames, another with 51frames A superframe has 1326 TDMA frames, which is composed of either fifty-one 26-frame multiframes or twenty-six 51-frame multiframes, and lasts for 6.12 s Then 2,038 superframes are grouped as a hyperframe, corresponding to a period of

Fig 2 3 Organization of frames

there is one base transceiver station (BTS), transmitting and receiving radio signals to/from MS The main tasks for a BTS are:

• Channel coding

• Ciphering and deciphering

• Burst formation, multiplexing, and modulation

• Evaluation and optimization of uplink and downlink transmissions

8.25 - bit guard period

26 - bit training sequence

1

1 1

1

1

25

24 25 50

0

0 Superframe

2 Fundamentals of Wireless Communications

frequency correction, synchronization, access, and dummy slot burst InFig 2.2,

3 h 28 min 53.760 s The organization of frames is plotted innFig 2.3

The cellular structure is adopted in GSM, as shown in Fig 2.4 In each cell,

Fig 2.4 Cellular network structure of GSM

A number of base stations are controlled by one base station controller (BSC).The BTSs and BSC form the base station subsystem The main responsibility of a BSC is to coordinate the handoff operation Therefore, a BSC will collect the measurement report of link quality from each mobile to decide whether a handoff

is necessary A BSC also needs the information of available resources in eachneighboring BTS During the handoff process, the BSC will coordinate the call transition from one BTS to another with the involved BTS and MS

Several BSCs are further controlled by the mobile switching center (MSC) TheMSC monitors the signaling between the MS and the core network, and performsswitching between the BTS and core network It is also responsible for resourcemanagement for each BTS

At the MSC, there are also home location register (HLR) and visitor locationregister (VLR) Calls between the mobile networks and fixed networks, e.g., public switched telephone network (PSTN), integrated service data network (ISDN), packet data network (PDN), public land mobile network (PLMN), etc are handled by a gateway called gateway mobile switching center (GMSC) The MSC, HLR, VLR, and GMSC are parts of the network and switching subsystem.Network management-related operations, such as administration, security,network configuration and performance management, maintenance, etc are theresponsibility of the operation subsystem The network control functions aremonitored by the operation and maintenance center The authentication center (AuC) and equipment identity register (EIR) are related to the security aspects.More specifically, the AuC is responsible for authentication and encryption, and the EIR stores equipment identity data The network architecture is described inFig 2.5

Fig 2.5 Network architecture of GSM

HLR and VLR are used to support user mobility When an MS is under anMSC different from its home MSC, the MS will register at the VLR of the MSC The VLR will also forward the user location information to the HLR When the

MS is called, its HLR is first queried for the current location Then the HLR willrespond with the MS’s current location, and the call is routed to the visiting MSC

2.2.2 Security-Related Aspects

In GSM, the following are related to security:

• Subscriber identity confidentiality

• Subscriber identity authentication

• Signaling information element confidentiality

• Data confidentiality

These are described in the following paragraphs

2 Fundamentals of Wireless Communications

PLMN

& Internet

PSTN ISDN PDN

BTS

BTS BTS

BTS BTS