本书由著名作者William Stallings编写，以当今网络安全的实际解决方案为基础，既简明扼要，又全面系统地介绍了网络安全的主要内容，包括基本原理、重要技术、主要方法和重要的工业标准等，既是高等学校网络安全基础课程的好教材，也是工程技术人员和网络爱好者了解网络安全基本概貌的好读物。

本书由著名作者William Stallings编写，以当今网络安全的实际解决方案为基础，既简明扼要，又全面系统地介绍了网络安全的主要内容，包括基本原理、重要技术、主要方法和重要的工业标准等。全书共包含11章。除第1章引言外，其余各章分为三大部分叙述：第一部分是密码学，重点介绍分组密码、流密码，消息认证码、安全杂凑函数、公钥密码和数字签名等的基本原理、主要方法和重要应用场景等，并简要介绍了几种常用的典型算法，包括DES算法、AES算法、RC4算法和RSA算法等；第二部分是网络安全应用，简要介绍了传输层安全中的SSL／TLS协议、无线局域网安全及WAP协议、电子邮件安全与PGP与SIM，ME协议、IP层安全与IPsec协议等。第三部分是系统安全，简要介绍了入侵检测与口令管理、恶意软件与防火墙等。

本书以最新和实用的网络安全知识为主题，采用深入浅出的叙述手法，每章末尾还给出一定的推荐读物和思考练习题。因此，本书既是高等学校网络安全基础课程的好教材，也是工程技术人员和网络爱好者了解网络安全基本概貌的好读物。

Preface ix

About the Author xiv

Chapter 1 Introduction 1

　1.1 Computer Security Concepts 3

　1.2 The OSI Security Architecture 8

　1.3 Security Attacks 9

　1.4 Security Services 13

　1.5 Security Mechanisms 16

　1.6 A Model for Network Security 19

　1.7 Standards 21

　1.8 Outline of This Book 21

　1.9 Recommended Reading 22

　1.10 Internet and Web Resources 23

　1.11 Key Terms, Review Questions, and Problems 25

　PART ONE CRYPTOGRAPHY 27

Chapter 2 Symmetric Encryption and Message Confidentiality 27

　2.1 Symmetric Encryption Principles 28

　2.2 Symmetric Block Encryption Algorithms 34

　2.3 Random and Pseudorandom Numbers 42

　2.4 Stream Ciphers and RC4 45

　2.5 Cipher Block Modes of Operation 50

　2.6 Recommended Reading and Web Sites 55

　2.7 Key Terms, Review Questions, and Problems 56

Chapter 3 Public-Key Cryptography and Message Authentication 61

　3.1 Approaches to Message Authentication 62

　3.2 Secure Hash Functions 67

　3.3 Message Authentication Codes 73

　3.4 Public-Key Cryptography Principles 79

　3.5 Public-Key Cryptography Algorithms 83

　3.6 Digital Signatures 90

　3.7 Recommended Reading and Web Sites 90

　3.8 Key Terms, Review Questions, and Problems 91

　PART TWO NETWORK SECURITY APPLICATIONS 97

Chapter 4 Key Distribution and User Authentication 97

　4.1 Symmetric Key Distribution Using Symmetric Encryption 98

　4.2 Kerberos 99

　4.3 Key Distribution Using Asymmetric Encryption 114

　4.4 X.509 Certificates 116

　4.5 Public-Key Infrastructure 124

　4.6 Federated Identity Management 126

　4.7 Recommended Reading and Web Sites 132

　4.8 Key Terms, Review Questions, and Problems 133

Chapter 5 Transport-Level Security 139

　5.1 Web Security Considerations 140

　5.2 Secure Socket Layer and Transport Layer Security 143

　5.3 Transport Layer Security 156

　5.4 HTTPS 160

　5.5 Secure Shell (SSH) 162

　5.6 Recommended Reading and Web Sites 173

　5.7 Key Terms, Review Questions, and Problems 173

Chapter 6 Wireless Network Security 175

　6.1 IEEE 802.11 Wireless LAN Overview 177

　6.2 IEEE 802.11iWireless LAN Security 183

　6.3 Wireless Application Protocol Overview 197

　6.4 Wireless Transport Layer Security 204

　6.5 WAP End-to-End Security 214

　6.6 Recommended Reading andWeb Sites 217

　6.7 Key Terms, Review Questions, and Problems 218

Chapter 7 Electronic Mail Security 221

　7.1 Pretty Good Privacy 222

　7.2 S/MIME 241

　7.3 DomainKeys Identified Mail 257

　7.4 Recommended Reading and Web Sites 264

　7.5 Key Terms, Review Questions, and Problems 265

　Appendix 7A Radix-64 Conversion 266

Chapter 8 IP Security 269

　8.1 IP Security Overview 270

　8.2 IP Security Policy 276

　8.3 Encapsulating Security Payload 281

　8.4 Combining Security Associations 288

　8.5 Internet Key Exchange 292

　8.6 Cryptographic Suites 301

　8.7 Recommended Reading and Web Sites 302

　8.8 Key Terms, Review Questions, and Problems 303

　PART THI~ SYSTEM SECURITY 305

Chapter 9 Intruders 305

　9.1 Intruders 307

　9.2 Intrusion Detection 312

　9.3 Password Management 323

　9.4 Recommended Reading andWeb sites 333

　9.5 Key Terms, Review Questions, and Problems 334

　Appendix 9A The Base-Rate Fallacy 337

Chapter 10 Malicious Soft-ware 340

　10.1 Types of Malicious Software 341

　10.2 Viruses 346

　10.3 Virus Countermeasures 351

　10.4 Worms 356

　10.5 Distributed Denial of Service Attacks 365

　10.6 Recommended Reading and Web Sites 370

　10.7 Key Terms, Review Questions, and Problems 371

Chapter 11 Firewalls 374

　11.1 The Need for Firewalls 375

　11.2 Firewall Characteristics 376

　11.3 Types of Firewalls 378

　11.4 Firewall Basing 385

　11.5 Firewall Location and Configurations 388

　11.6 Recommended Reading andWeb Site 393

　11.7 Key Terms, Review Questions, and Problems 394

　APPENDICES 398

　Appendix A Some Aspects of Number Theory 398

　A.1 Prime and Relatively Prime Numbers 399

　A.2 Modular Arithmetic 401

　Appendix B Projects for Teaching Network Security 403

　B.1 Research Projects 404

　B.2 Hacking Project 405

　B.3 Programming Projects 405

　B.4 Laboratory Exercises 406

　B.5 Practical Security Assessments 406

　B.6 Writing Assignments 406

　B.7 Reading/Report Assignments 407

　Index 408

　ONLINE CHAPTERS

Chapter 12 Network Management Security

　12.1 Basic Concepts of SNMP

　12.2 SNMPvl Community Facility

　12.3 SNMPv3

　12.4 Recommended Reading and Web Sites

　12.5 Key Terms, Review Questions, and Problems

Chapter 13 Legal and Ethical Aspects

　13.1 Cybercrime and Computer Crime

　13.2 Intellectual Property

　13.3 Privacy

　13.4 Ethical Issues

　13.5 Recommended Reading and Web Sites

　13.6 Key Terms, Review Questions, and Problems

　ONLINE APPENDICES

Appendix C Standards and Standards-Setting Organizations

　C.1 The Importance of Standards

　C.2 Internet Standards and the Internet Society

　C.3 National Institute of Standards and Technology

Appendix D TCP/IP and OSI

　D.1 Protocols and Protocol Architectures

　D.2 The TCP/IP Protocol Architecture

　Do3 The Role of an Internet Protocol

　D.4 IPv4

　D.5 IPv6

　D.6 The OSI Protocol Architecture

Appendix E Pseudorandom Number Generation

　E.1 PRNG Requirements

　E.2 PRNG Using a Block Cipher

　E.3 PRNG Using a Hash Function or Message Authentication Code

Appendix F Kerberos Encryption Techniques

　E.1 Password-to-Key Transformation

　E.2 Propagating Cipher Block Chaining Mode

Appendix G Data Compression Using ZIP

　G.1 Compression Algorithm

　G.2 Decompression Algorithm

Appendix H PGP Random Number Generation

　H.1 True Random Numbers

　H.2 Pseudorandom Numbers

Appendix I The International Reference Alphabet

Glossary

References