Networking Fundamentals

Kaveh Pahlavan, is a Professor of Electrical and Computer Engineering (ECE), a Professor of Computer Science (CS), and Director of the Center for Wireless Information Network Studies, Worcester Polytechnic Institute (WPI), Worcester, MA. He is also a visiting Professor of Telecommunication Laboratory and CWC, University of Oulu, Finland. His area of research is location-aware broadband wireless indoor networks. He has contributed to numerous seminal technical publications and patents in this field. He is the principal author of the Wireless Information Networks (with Allen Levesque), John Wiley and Sons, 1995 and Principles of Wireless Networks -- A Unified Approach (with P. Krishnamurthy), Prentice Hall, 2002. He has been a consultant to a number of companies, including CNR Inc., GTE Laboratories, Steinbrecher Corp., Simplex, Mercury Computers, WINDATA, SieraComm, 3COM, and Codex/Motorola in Massachusetts; JPL, Savi Technologies, RadioLAN in California; Aironet in Ohio; United Technology Research Center in Connecticut; Honeywell in Arizona; Nokia, LK-Products, Elektrobit, TEKES, the Finnish Academy in Finland; and NTT in Japan. Before joining WPI, he was the director of advanced development at Infinite Inc., Andover, MA, working on data communications. He started his career as an assistant professor at Northeastern University, Boston, MA. He is the Editor-in-Chief of the International Journal on Wireless Information Networks. He was the founder, the program chairman, and organizer of the IEEE Wireless LAN Workshop, Worcester, in 1991 and 1996 and the organizer and technical program chairman of the IEEE International Symposium on Personal, Indoor, and Mobile Radio Communications, Boston, MA, 1992 and 1998. He has also been selected as a member of the Committee on Evolution of Untethered Communication, US National Research Council, 1997 and has led the US review team for the Finnish R&D Programs in Electronic and Telecommunication in 1999 and NETs project in 2003. For his contributions to the wireless networks he was the Westin Hadden Professor of Electrical and Computer Engineering at WPI during 1993--1996, was elected as a fellow of the IEEE in 1996 and became a fellow of Nokia in 1999. From May to December of 2000 he was the first Fulbright--Nokia scholar at the University of Oulu, Finland. Because of his inspiring visionary publications and his international conference activities for the growth of the wireless LAN industry, he is referred to as one of the founding fathers of the wireless LAN industry. In the past few years his research work has been the core for more than 25 patents by Skyhook Wireless, where he acts as the chief technical advisor. In January 2008 Steve Jobs announced that Skyhook Wireless’s WiFi localization technology is used in iPhone. Details of his contributions to this field are available at www.cwins.wpi.edu. Prashant Krishnamurthy is an associate professor with the graduate program in Telecommunications and Networking at the University of Pittsburgh. At Pitt, he regularly teaches courses on cryptography, network security, and wireless communications and networks. His research interests are wireless network security, wireless data networks, and position location in indoor wireless networks. He is the coauthor of the books Principles of Wireless Networks -- A Unified Approach and Physical Layer of Communication Systems and is a co-editor of Information Assurance: Dependability and Security in Networked Systems. He served as the chair of the IEEE Communications Society Pittsburgh Chapter from 2000 to 2005. He obtained his PhD from Worcester Polytechnic Institute, Worcester, MA, in 1999.

About the Authors xiii

Preface xv

1 Introduction to Information Networks 1

1.1 Introduction 1

1.1.1 Elements of Information Networks 3

1.1.2 Chronology of Information Networks 5

1.1.3 Standards Organizations for Information Networking 7

1.1.4 Evolution of Long-Haul Multiplexing Standards 10

1.2 Evolution of Wide-Area Networks 13

1.2.1 Evolution of the Public Switched Telephone Network 14

1.2.2 Emergence of the Internet 15

1.2.3 HFC Infrastructure for Cable TV 17

1.2.4 Evolution of Cellular Telephone Networks 17

1.3 Evolution of Local Networks 18

1.3.1 Evolution of Local Access to Public Switched Telephone Network 19

1.3.2 Evolution of the IEEE 802.3 Ethernet 21

1.3.3 Evolution of the IEEE 802.11 Wireless Local-Area Network 22

1.3.4 Internet Access to Home and IEEE 802.16 24

1.3.5 Evolution of IEEE 802.15 Wireless Personal-Area Networks 28

1.4 Structure of the Book 30

Questions 31

Project 1 32

Part One: Fundamentals of Transmission and Access 33

2 Characteristics of the Medium 35

2.1 Introduction 35

2.2 Guided Media 36

2.2.1 Twisted Pair 38

2.2.2 Coaxial Cables 42

2.2.3 Optical Fiber 45

2.3 Wireless Media 48

2.3.1 Radio Propagation Mechanisms 49

2.3.2 Path-Loss Modeling and Signal Coverage 50

2.3.3 Path-Loss Models for Indoor Areas 56

2.3.4 Path-Loss Models for Outdoor Areas 60

2.3.5 Effects of Multipath and Doppler 62

2.3.6 Emerging Channel Models 68

Questions 72

Problems 73

Project 1: Simulation of Multipath Fading 77

Project 2: The RSS in IEEE 802.11 78

Project 3: Coverage and Data Rate Performance of the IEEE 802.11B/G WLANs 79

3 Fundamentals of Physical Layer Transmission 83

3.1 Information Transmission 83

3.1.1 Wired and Wireless Transmission 84

3.1.2 Baseband Transmission 87

3.2 Transmission Techniques and Signal Constellation 89

3.2.1 Multisymbol Digital Communications 90

3.2.2 Signal Constellation in Digital Communications 91

3.2.3 Two-Dimensional Signal Constellations 94

3.2.4 Channel Capacity 100

3.3 Performance of the Physical Layer 102

3.3.1 Effects of Fading on Performance over Wireless Channels 105

3.3.2 Diversity Techniques 107

3.4 Wideband Modems 109

3.4.1 Spread-Spectrum Transmissions 110

3.4.2 Orthogonal Frequency-Division Multiplexing 115

3.4.3 Space–Time Coding 117

3.4.4 Capacity Multiple-Input–Multiple-Output Antenna Systems 118

Questions 119

Problems 120

Projects 123

4 Coding and Reliable Packet Transmission 125

4.1 Introduction 125

4.2 Source Coding and Framing Techniques 127

4.2.1 Information Source and Coding 127

4.2.2 Framing Techniques 130

4.3 FEC Coding 132

4.3.1 Fundamentals of Coding 132

4.3.2 Block Codes 136

4.3.3 Convolutional Codes 141

4.3.4 Codes for Manipulating Data 145

4.4 Coding for Spread-Spectrum and Code-Division Multiple Access Systems 147

4.4.1 Pseudo Noise Codes 148

4.4.2 M-ary Orthogonal Codes 149

4.5 ARQ Schemes 151

4.5.1 Stop and Wait 151

4.5.2 Go-Back-N 153

4.5.3 Selective-Repeat Automatic Repeat Request 153

4.5.4 Hybrid Automatic Repeat Request 154

4.6 Flow Control Protocols 155

4.6.1 Stop and Wait 156

4.6.2 Sliding Window 158

Questions 159

Problems 159

5 Medium Access Methods 165

5.1 Introduction 165

5.2 Centralized Assigned Access Schemes 167

5.2.1 Frequency-Division Multiple Access 168

5.2.2 Time-Division Multiple Access 171

5.2.3 Code-Division Multiple Access 174

5.2.4 Comparison of Code-, Time-, and Frequency-Division Multiple Access 177

5.2.5 Performance of Assigned Access Methods 180

5.3 Distributed Random Access Schemes 184

5.3.1 Random Access Methods for Data Services 184

5.3.2 Access Methods for Local-Area Networks 191

5.3.3 Performance of Random Access Methods 196

5.4 Integration of Voice and Data Traffic 205

5.4.1 Access Methods for Integrated Services 205

5.4.2 Data Integration in Voice-Oriented Networks 205

5.4.3 Voice Integration into Data-Oriented Networks 211

Questions 217

Problems 218

Projects 222

Part Two: Wide-Area Networks 225

6 The Internet 227

6.1 Introduction: Internet Infrastructure 227

6.1.1 Fundamentals of Packet Forwarding 229

6.2 Addressing 230

6.2.1 ISDN Addressing in Connection-Based PSTN 231

6.2.2 MAC Addressing in Connectionless Local-Area Networks 233

6.2.3 IP Addressing in the Connectionless Internet 235

6.3 Quality of Service 239

6.3.1 Quality of Service in Connection-Based Networks 240

6.3.2 Quality of Service in Connectionless Networks 241

6.4 Bridges 242

6.4.1 Standardization and Bridges 244

6.4.2 IEEE 802.1D Transparent Bridges 244

6.4.3 The Spanning-Tree Algorithm 246

6.4.4 IEEE 802.5 Source Routing Bridging 250

6.4.5 IEEE 802.1Q Virtual Local-Area Network 250

6.5 Switches 251

6.5.1 Circuit Switching in Public Switched Telephone Network 252

6.5.2 Integrated Service Data Network Switching 252

6.5.3 Packet Switching over Public Switched Telephone Network 253

6.5.4 Asynchronous Transfer Mode 254

6.6 Routers 260

6.6.1 Types of Router 262

6.6.2 Network Protocols for Routers 264

6.6.3 Routing Algorithms 269

6.6.4 Multiprotocol Label Switching 275

Questions 277

Problems 278

Project 1: Client-Server Programming 280

7 Cellular Networks 281

7.1 Introduction 282

7.1.1 The Cellular Concept 282

7.1.2 Cellular Hierarchy 285

7.2 General Architecture of a Cellular Network 286

7.2.1 Mobile Stations 288

7.2.2 The Base Station Subsystem 288

7.2.3 The Network and Switching Subsystem 289

7.3 Mechanisms to Support a Mobile Environment 290

7.3.1 Registration 290

7.3.2 Call Establishment 291

7.3.3 Handoff 293

7.3.4 Security 295

7.4 Protocol Stack in Cellular Networks 297

7.4.1 Layer 1: Physical Layer 298

7.4.2 Layer 2: Data Link Layer 299

7.4.3 Layer 3: Networking Layer 300

7.5 Physical Layer in TDMA Air Interface 302

7.5.1 Modulation Technique 302

7.5.2 Power and Power Control 304

7.5.3 Physical Packet Bursts 304

7.6 Physical Layer in CDMA Air Interface 310

7.6.1 CDMA Forward Channels 310

7.6.2 CDMA Reverse Channels 315

7.6.3 Packet and Frame Formats in a Typical CDMA Network 317

7.6.4 Other Variations in CDMA Air Interface 319

7.7 Achieving Higher Data Rates in Cellular Networks 320

7.7.1 Changes in Reference Architecture to Connect to Internet 321

7.7.2 How to Achieve High Data Rates 322

7.8 Deployment of Cellular Networks 325

7.8.1 Cell Fundamentals and Frequency Reuse 325

7.8.2 Capacity Expansion Techniques for Frequency-/Time-Division Multiple Access Systems 330

7.8.3 Network Planning for Code-Division Multiple Access Systems 335

Questions 337

Problems 338

Part Three: Local and Personal-Area Networks 343

8 IEEE 802.3 Ethernet 345

8.1 Introduction 345

8.2 Legacy Ethernet 349

8.2.1 The Packet Format and the Physical Layer 351

8.2.2 Carrier Sense Multiple Access with Collision Detection for the Medium Access Control Layer 352

8.2.3 Medium Access Control Performance 355

8.2.4 Alternatives to Legacy Ethernet 358

8.2.5 Early Enhancements to Legacy Ethernet 359

8.3 Evolution of the Physical Layer 361

8.3.1 Fast Ethernet at 100 Mb/s 361

8.3.2 Alternative for Fast Ethernet 368

8.3.3 Gigabit Ethernet 370

8.3.4 10 Gb/s Ethernet and Beyond 374

8.4 Emergence of Additional Features for Ethernet 379

8.4.1 Frame Format for the Virtual Local-Area Network 379

8.4.2 Full-Duplex Operation 381

8.4.3 PAUSE Frames 382

8.4.4 Link Aggregation 384

Questions 385

Problems 386

9 IEEE Wireless Local-Area Network Standards 389

9.1 Introduction 389

9.1.1 Early Experiences 390

9.1.2 Emergence of Unlicensed Bands 391

9.1.3 Products, Bands, and Standards 392

9.1.4 Shift in Marketing Strategy 393

9.2 IEEE 802.11 and WLANs 395

9.2.1 Overview of IEEE 802.11 396

9.2.2 IEEE 802.11 Wireless Local-Area Network Operations 398

9.2.3 The IEEE 802.11 Medium Access Control Layer 402

9.2.4 The Physical Layer 410

9.2.5 Deployment of Wireless Local-Area Networks 419

9.2.6 Security Issues and Implementation in IEEE 802.11 425

9.2.7 Wireless Local-Area Network Standards and 802.11 Standards Activities 428

9.3 IEEE 802.16 (WiMAX) 430

9.3.1 General Architecture 432

9.3.2 Physical Layer 433

9.3.3 Medium Access Control Layer of WiMAX 434

Questions 435

Problems 436

Projects 441

10 IEEE 802.15 Wireless Personal-Area Network 443

10.1 Introduction 443

10.1.1 IEEE 802.15 Wireless Personal-Area Network Standardization Series 444

10.2 IEEE 802.15.1 Bluetooth 445

10.2.1 Overall Architecture 447

10.2.2 Protocol Stack 448

10.2.3 Physical Connection 450

10.2.4 Medium Access Control Mechanism 452

10.2.5 Frame Formats 452

10.2.6 Connection Management 458

10.2.7 Security 460

10.3 Interference between Bluetooth and 802.11 460

10.3.1 Interference Range 461

10.3.2 Probability of Interference 465

10.3.3 Empirical Results 468

10.4 IEEE 802.15.3A Ultra Wideband Wireless Personal-Area Networks 470

10.4.1 Direct Sequence Ultra Wideband 470

10.4.2 Multiband Orthogonal Frequency-Division Multiplexing 474

10.5 IEEE 802.15.4 ZigBee 477

10.5.1 Overall Architecture 478

10.5.2 Protocol Stack 479

10.5.3 Medium Access Control Layer 480

10.5.4 Physical Layer 481

10.5.5 Frame Format 483

10.5.6 Comparison of ZigBee with Bluetooth and WiFi 484

Questions 485

Problems 486

Part Four: System Aspects 489

11 Network Security 491

11.1 Introduction 491

11.2 Network Attacks and Security Issues 492

11.2.1 Network Communications 492

11.2.2 Why Security Attacks are Possible 494

11.2.3 Some Example Security Attacks 498

11.2.4 Defining Security Attacks, Services, and Architecture 504

11.3 Protection and Prevention 505

11.3.1 Firewalls and Perimeter Security 505

11.3.2 Cryptography and Cryptographic Protocols 508

11.3.3 Preventing Successful Phishing Attacks 523

11.4 Detection 523

11.5 Assessment and Response 524

Questions 526

Problems 526

Projects 528

12 Wireless Localization 529

12.1 Introduction 529

12.2 What is Wireless Geolocation? 530

12.2.1 Wireless Emergency Services 532

12.2.2 Performance Measures for Geolocation Systems 533

12.3 Radio-Frequency Location Sensing and Positioning Methodologies 534

12.3.1 Generic Architecture 534

12.3.2 Positioning Algorithms 536

12.3.3 Positioning Standards for Cellular Telephone Systems 544

12.4 LCS Architecture for Cellular Systems 546

12.4.1 Cellular Network Architecture 548

12.4.2 Location Services Architecture 549

12.4.3 Over the Air (Access Network) Communications for Location Services 551

12.4.4 Signaling in the Fixed Infrastructure (Core Network) for Location Services 552

12.4.5 The Mobile Location Protocol 553

12.5 Positioning in Ad Hoc and Sensor Networks 554

Questions 555

Problems 556

Projects 556

13 Wireless Sensor Networks 559

13.1 Introduction 559

13.2 Sensor Network Applications 560

13.2.1 Habitat Monitoring 560

13.2.2 Structural Health Monitoring 561

13.2.3 Miscellaneous Applications 561

13.3 Sensor Network Architecture and Sensor Devices 561

13.3.1 Sensor Network Architecture 562

13.3.2 Overview of Sensor Devices 564

13.3.3 Commercial Sensors 566

13.3.4 Future Directions 568

13.4 The Physical Layer in Sensor Networks 570

13.4.1 Spectrum 570

13.4.2 Path Loss 571

13.4.3 Gray Zone 572

13.4.4 Modulation Schemes 573

13.5 The MAC Layer in Sensor Networks 574

13.5.1 Issues in Medium Access for Sensor Networks 575

13.5.2 IEEE 802.15.4 Medium Access Control 577

13.5.3 Low-Duty-Cycle Medium Access Controls 578

13.5.4 Low-Latency Medium Access Controls 579

13.6 Higher Layer Issues in Sensor Networks 580

13.6.1 Establishing the Sensor Network 581

13.6.2 Routing 583

13.6.3 Coverage, Connectivity, and Topology Control 585

13.6.4 Synchronization 587

13.6.5 Security 588

Questions 591

References 593

Appendix A: What is Decibel? 605

Appendix B: STC for Two Transmitters and One Receiver 607

Appendix C: Source Coding 611

C.1 Source Coding for Voice 611

C.2 Source Coding for Images and Video 613

Appendix D: Acronyms 615

Appendix E: List of Variables 627

Index 633