《数据和计算机通信》(第八版)对整个数据通信、组网和协议领域给出了清晰、完整、统一的视图。WilliamStallings教授将这一宏大的主题分解成小而详尽的元素，通过逐步地讲解，完整展现了最新技术的全貌。Stallings彻底修订了这本全球畅销书，以充分体现今天的最新技术进步，包括WiFi和10 Gbps以太网、先进的拥塞控制以及IP性能度量技术。

《数据与计算机通信(第8版英文版)》是著名计算机专业作家William Stallings的经典著作之一，内容涉及最基本的数据通信原理、各种类型的计算机网络及多种网络协议和应用。这一版对原有内容做了彻底的修订和重组，使新版对通信各专题的阐述更全面、更清晰。同时，新版更新了吉比特以太网、10 Gbps以太网的内容，对WiFi/IEEE 802.11无线局域网、性能监控、服务水平约定、服务质量等根据新的标准进行了修订。此外，本书还涉及TCP Tahoe、Reno以及New Reno拥塞控制算法的描述，对多媒体组网的内容也进行了扩充。每章都附有习题和建议，以便读者进一步阅读。本书包含的大量扩展性知识包含在配套网站http://WilliamStallings.com/DCC/DCC8e.html中，供教师和学生参考。

《数据与计算机通信(第8版英文版)》可供通信或计算机、信息技术专业的本科生或研究生使用，同时也可供广大通信或计算机领域相关人员参考。

PART ONE OVERVIEW 1

Chapter 1 Data Communications, Data Networking, and the Internet 1

 1.1 Data Communications and Networking for Today's Enterprise 3

 1.2 A Communications Model 7

 1.3 Data Communications 10

 1.4 Networks 13

 1.5 The Internet 16

 1.6 An Example Configuration 20

Chapter 2 Protocol Architecture, TCP/IP, and Internet-Based Applications 23

 2.1 The Need for a ProtocolArchitecture 24

 2.2 TheTCP/IP ProtocolArchitecture 25

 2.3 The OSI Model 33

 2.4 Standardization within a ProtocolArchitecture 35

 2.5 Traditional lnternet-BasedApplications 39

 2.6 Multimedia 39

 2.7 Recommended Reading 44

 2.8 Problems 45

 Appendix 2A The Trivial File Transfer Protocol 47

PART TWO DATA COMMUNICATIONS 52

Chapter 3 Data Transmission 52

 3.1 Concepts and Terminology 54

 3.2 Analog and Digital Data Transmission 65

 3.3 Transmission Impairments 73

 3.4 Channel Capacity 78

 3.5 Recommended Reading 83

 3.6 Problems 83

 Appendix 3A Decibels and Signal Strength 86

Chapter 4 Transmission Media 89

 4.1 Guided Transmission Media 91

 4.2 Wireless Transmission 104

 4.3 Wireless Propagation 112

 4.4 Line-of-Sight Transmission 116

 4.5 Recommended Reading 120

 4.6 Problems 121

Chapter 5 Signal Encoding Techniques 124

 5.1 Digital Data, Digital Signals 127

 5.2 Digital Data, Analog Signals 137

 5.3 Analog Data, Digital Signals 148

 5.4 Analog Data, Analog Signals 154

 5.5 Recommended Reading 161

 5.6 Problems 161

Chapter 6 Digital Data Communication Techniques 165

 6.1 Asynchronous and Synchronous Transmission 167

 6.2 Types of Errors 171

 6.3 Error Detection 171

 6.4 Error Correction 181

 6.5 Line Configurations 186

 6.6 Recommended Reading 188

 6.7 Problems 189

Chapter 7 Data Link Control Protocols 192

 7.1 Flow Control 194

 7.2 Error Control 2{}1

 7.3 High-Level Data Link Control (HDLC) 207

 7.4 Recommended Reading 213

 7.5 Problems 214

 Appendix 7 A Performance Issues 216

Chapter 8 Multiplexing 223

 8.1 Frequency-Division Multiplexing 226

 8.2 Synchronous Time-Division Multiplexing 232

 8.3 Statistical Time-Division Multiplexing 242

 8.4 Asymmetric Digital Subscriber Line 249

 8.5 xDSL 252

 8.6 Recommended Reading 253

 8.7 Problems 254

Chapter 9 Spread Spectrum 257

 9.1 The Concept of Spread Spectrum 259

 9.2 Frequency Hopping Spread Spectrum 260

 9.3 Direct Sequence Spread Spectrum 265

 9.4 Code-Division Multiple Access 270

 9.5 Recommended Reading 273

 9.6 Problems 273

PART THREE WIDE AREA NETWORKS 277

Chapter 10 Circuit Switching and Packet Switching 277

 10.1 Switched Communications Networks 279

 10.2 Circuit Switching Networks 281

 10.3 Circuit Switching Concepts 284

 10.4 Softswitch Architecture 287

 10.5 Packet-Switching Principles 289

 10.6 X.25 297

 10.7 Frame Relay 299

 10.8 Recommended Reading 304

 10.9 Problems 304

Chapter 11 Asynchronous Transfer Mode 307

 11.1 Protcol Architecture 308

 11.2 ATM Logical Connections 310

 11.3 ATM Cells 314

 11.4 Transmission of ATM Cells 319

 11.5 ATM Service Categories 324

 11.6 Recommended Reading 327

 11.7 Problems 328

Chapter 12 Routing in Switched Networks 330

 12.1 Routing in Packet-Switching Networks 331

 12.2 Examples: Routing in ARPANET 341

 12.3 Least-Cost Algorithms 346

 12.4 Recommended Reading 351

 12.5 Problems 352

Chapter 13 Congestion Control in Data Networks 355

 13.1 Effects of Congestion 357

 13.2 Congestion Control 361

 13.3 Traffic Management 364

 13.4 Congestion Control in Packet-Switching Networks 365

 13.5 Frame Relay Congestion Control 366

 13.6 ATM Traffic Management 372

 13.7 ATM-GFR Traffic Management 384

 13.8 Recommended Reading 387

 13.9 Problems 388

Chapter 14 Cellular Wireless Networks 391

 14.1 Principles of Cellular Networks 393

 14.2 First Generation Analog 405

 14.3 Second Generation CDMA 407

 14.4 Third Generation Systems 415

 14.5 Recommended Reading 418

 14.6 Problems 419

PART FOUR LOCAL AREA NETWORKS 421

Chapter 15 Local Area Network Overview 421

 15.1 Background 423

 15.2 Topologies and Transmission Media 426

 15.3 LAN Protocol Architecture 432

 15.4 Bridges 440

 15.5 Layer 2 and Layer 3 Switches 448

 15.6 Recommended Reading 453

 15.7 Problems 454

Chapter 16 High-Speed LANs 456

 16.1 The Emergence of High-Speed LANs 457

 16.2 Ethernet 459

 16.3 Fibre Channel 474

 16.4 Recommended Reading 478

 16.5 Problems 480

 Appendix 16A Digital Signal Encoding for LANs 481

 Appendix 16B Performance Issues 487

 Appendix 16C Scrambling 492

Chapter 17 Wireless LANs 495

 17.1 Overview 496

 17.2 Wireless LAN Technology 501

 17.3 IEEE 802.11 Architecture and Services 504

 17.4 IEEE 802.11 Medium Access Control 508

 17.5 IEEE 802.11Physical Layer 516

 17.6 IEEE 802.11 Security Considerations 522

 17.7 Recommended Reading 523

 17.8 Problems 524

PART FIVE INTERNET AND TRANSPORT PROTOCOLS 526

Chapter 18 Internetwork Protocols 526

 18.1 Basic Protocol Functions 528

 18.2 Principles oflnternetworking 536

 18.3 Internet Protocol Operation 539

 18.4 lnternet Protocol 546

 18.5 IPv6 556

 18.6 Virtual Private Networks and IP Security 566

 18.7 Recommended Reading 569

 18.8 Problems 570

Chapter 19 Internetwork Operation 573

 19.1 Multicasting 575

 19.2 Routing Protocols 584

 19.3 Integrated Services Architecture 595

 19.4 Differentiated Services 606

 19.5 Service Level Agreements 615

 19.6 IP Performance Metrics 616

 19.7 Recommended Reading 619

 19.8 Problems 621

Chapter 20 Transport Protocols 624

 20.1 Connection-Oriented Transport Protocol Mechanisms 626

 20.2 TCP 643

 20.3 TCP Congestion Control 652

 20.4 UDP 662

 20.5 Recommended Reading 664

 20.6 Problems 664

PART SIX INTERNET APPLICATIONS 667

Chapter 21 Network Security 667

 21.1 Security Requirements and Attacks 669

 21.2 Confidentiality with Conventional Encryption 671

 21.3 Message Authentication and Hash Functions 679

 21.4 Public-Key Encryption and Digital Signatures 686

 21.5 Secure Socket Layer and Transport Layer Security 693

 21.6 IPv4 and IPv6 Security 698

 21.7 Wi-Fi Protected Access 703

 21.8 Recommended Reading 705

 21.9 Problems 706

Chapter 22 Internet Applications--Electronic Mail and Network Management 708

 22.1 Electronic Mail: SMTP and MIME 710

 22.2 Network Management: SNMP 725

 22.3 Recommended Reading 735

 22.4 Problems 736

Chapter 23 Internet Applications--Internet Directory Service and World Wide Web 738

 23.1 lnternet Directory Service: DNS 739

 23.2 WebAccess: HTTP 749

 23.3 Recommended Reading 760

 23.4 Problems 761

Chapter 24 Internet Applications--Multimedia 763

 24.1 Audio andVideo Compression 764

 24.2 Real-Time Traffic 772

 24.3 Voice Over lP and Multimedia Support--SIP 775

 24.4 Real-Time Transport Protocol (RTP) 784

 24.5 Recommended Reading 795

 24.6 Problems 796

APPENDICES 797

Appendix Projects and Other Student Exercises for Teaching Data and Computer Communications 797

 A.1 Practical Exercises 798

 A.2 Sockets Projects 799

 A.3 Ethereal Projects 799

 A.4 Simulation and Modeling Projects 800

 A.5 Performance Modeling 800

 A.6 Research Projects 801

 A.7 Reading/Report Assignments 801

 A.8 Writing Assignments 801

 A.9 Discussion Topics 802

References 803

Index 814