CONTENTS
CHAPTER 1 OVERVIEW 1
1.1 Services, Mechanisms, and Attacks 4
1.2 The OSI Security Architecture 7
1.3 A Model for Network Security 14
1.4 Outline of This Book 17
1.5 Recommended Reading 17
1.6 Internet and Web Resources 18
PART ONE SYMMETRIC CIPHERS 21
CHAPTER 2 CLASSICAL ENCRYPTION TECHNIQUES 23
2.1 Symmetric Cipher Model 24
2.2 Substitution Techniques 30
2.3 Transposition Techniques 44
2.4 Rotor Machines 46
2.5 Steganography 47
2.6 Recommended Reading and Web Sites 49
2.7 Key Terms, Review Questions, and Problems 50
CHAPTER 3 BLOCK CIPHERS AND THE DATA ENCRYPTION STANDARD 55
3.1 Simplified DES 56
3.2 Block Cipher Principles 63
3.3 The Data Encryption Standard 72
3.4 The Strength of DES 82
3.5 Differential and Linear Cryptanalysis 83
3.6 Block Cipher Design Principles 86
3.7 Block Cipher Modes of Operation 90
3.8 Recommended Reading 98 .
3.9 Key Terms, Review Questions, and Problems 99
CHAPTER 4 INTRODUCTION TO FINITE FIELDS 103
4.1 Groups, Rings, and Fields 104
4.2 Modular Arithmetic 107
4.3 Euclid's Algorithm 115
4.4 Finite Fields of the Form GF(p) 117
4.5 Polynomial Arithmetic 121
4.6 Finite Fields of the Form GF(2") 126
4.7 Recommended Reading and Web Sites 134
4.8 Key Terms, Review Questions, and Problems 134
CHAPTER 5 ADVANCED ENCRYPTION STANDARD 139
5.1 Evaluation Criteria for AES 140
5.2 The AES Cipher 143
5.3 Recommended Reading and Web Sites 167
5.4 Key Terms, Review Questions, and Problems 167
Appendix 5A Polynomials with Coefficients in GF(28) 169
CHAPTER 6 CONTEMPORARY SYMMETRIC CIPHERS 173
6.1 Triple DES 174
6.2 Blowfish 179
6.3 RC5 185
6.4 Characteristics of Advanced Symmetric Block Ciphers
6.5 RC4 Stream Ciper 192
6.6 Recommended Reading and Web Sites 197
6.7 Key Terms, Review Questions, and Problems 197
CHAPTER 7 CONFIDENTIALITY USING SYMMETRIC ENCRYPTION 201
7.1 Placement of Encryption Function 202
7.2 Traffic Confidentiality 210
7.3 Key Distribution 211
7.4 Random Number Generation 220
7.5 Recommended Reading and Web Site 227
7.6 Key Terms, Review Questions, and Problems 228
PART TWO PUBLIC-KEY ENCRYPTION AND HASH FUNCTIONS 233
CHAPTER 8 INTRODUCTION TO NUMBER THEORY 235
8.1 Prime Numbers 236
8.2 Fermat's and Euler's Theorems 239
8.3 Testing for Primality 243
8.4 The Chinese Remainder Theorem 245
8.5 Discrete Logarithms 248
8.6 Recommended Reading and Web Site 252
8.7 Key Terms, Review Questions, and Problems 253
CHAPTER 9 PUBLIC-KEY CRYPTOGRAPHY AND RSA 257
9.1 Principles of Public-Key Cryptosystems 259
9.2 The RSA Algorithm 268
9.3 Recommended Reading and Web Site 278
9.4 Key Terms, Review Questions, and Problems 279
Appendix 9A The Complexity of Algorithms 282
CHAPTER 10 KEY MANAGEMENT; OTHER PUBLIC-KEY CRYPTOSYSTEMS 285
10.1 Key Management 286
10.2 Diffie-Hellman Key Exchange 293
10.3 Elliptic Curve Arithmetic 297
10.4 Elliptic Curve Cryptography 304
10.5 Recommended Reading and Web Site 308
10.6 Key Terms, Review Questions, and Problems 308
CHAPTER 11 MESSAGE AUTHENTICATION AND HASH FUNCTIONS 311
11.1 Authentication Requirements 312
11.2 Authentication Functions 313
11.3 Message Authentication Codes 324
11.4 Hash Functions 328
11.5 Security of Hash Functions and MACs 335
11.6 Recommended Reading 338
11.7 Key Terms, Review Questions, and Problems 339
Appendix 11A Mathematical Basis of the Birthday Attack 340
CHAPTER 12 HASH ALGORITHMS 347
12.1 MD5 Message Digest Algorithm 348
12.2 Secure Hash Algorithm 357
12.3 RIPEMD-160 365
12.4 HMAC 372
12.5 Recommended Reading and Web Sites 377
12.6 Key Terms, Review Questions, and Problems 377
CHAPTER 13 DIGITAL SIGNATURES AND AUTHENTICATION PROTOCOLS 379
13.1 Digital Signatures 380
13.2 Authentication Protocols 384
13.3 Digital Signature Standard 392
13.4 Recommended Reading 395
13.5 Key Terms, Review Questions, and Problems 395
PART THREE NETWORK SECURITY PRACTICE 399
CHAPTER 14 AUTHENTICATION APPLICATIONS 401
14.1 Kerberos 402
14.2 X.509 Authentication Service 419
14.3 Recommended Reading and Web Sites 428
14.4 Key Terms, Review Questions, and Problems 429
Appendix 14A Kerberos Encryption Techniques 431
CHAPTER 15 ELECTRONIC MAIL SECURITY 435
15.1 Pretty Good Privacy 436
15.2 S/MIME 455
15.3 Recommended Web Sites 472
15.4 Key Terms, Review Questions, and Problems 472
Appendix 15A Data Compression Using ZIP 473
Appendix 15B Radix-64 Conversion 476
Appendix 15C PGP Random Number Generation 478
CHAPTER 16 IP SECURITY 481
16.1 IP Security Overview 482
16.2 IP Security Architecture 485
16.3 Authentication Header 491
16.4 Encapsulating Security Payload 496
16.5 Combining Security Associations 501
16.6 Key Management 504
16.7 Recommended Reading and Web Sites 515
16.8 Key Terms, Review Questions, and Problems 516
Appendix 16A Internetworking and Internet Protocols 517
CHAPTER 17 WEB SECURITY 527
17.1 Web Security Considerations 528
17.2 Secure Sockets Layer and Transport Layer Security 531
17.3 Secure Electronic Transaction 548
17.4 Recommended Reading and Web Sites 560
17.5 Key Terms, Review Questions, and Problems 560
PART FOUR SYSTEM SECURITY 563
CHAPTER 18 INTRUDERS 565
18.1 Intruders 566
18.2 Intrusion Detection 569
18.3 Password Management 581
18.4 Recommended Reading and Web Sites 591
18.5 Key Terms, Review Questions, and Problems 592
Appendix 18A The Base-Rate Fallacy 594
CHAPTER 19 MALICIOUS SOFTWARE 597
19.1 Viruses and Related Threats 598
19.2 Virus Countermeasures 609
19.3 Recommended Reading and Web Site 613
19.4 Key Terms, Review Questions, and Problems 614
CHAPTER 20 FIREWALLS 615
20.1 Firewall Design Principles 616
20.2 Trusted Systems 628
20.3 Recommended Reading and Web Site 634
20.4 Key Terms, Review Questions, and Problems 634
APPENDICES
APPENDIX A STANDARDS AND STANDARDS-SETTING ORGANIZATIONS 637
A.l The Importance of Standards 638
A.2 Standards and Regulation 639
A.3 Internet Standards and the Internet Society 640
A.4 National Institute of Standards and Technology 634
A.5 Standards and Specifications Cited in this Book 644
APPENDIX B PROJECTS FOR TEACHING CRYPTOGRAPHY AND NETWORK SECURITY 647
B.l Research Projects 648
B.2 Programming Projects 649
B.3 Reading/Report Assignments 649
GLOSSARY 651
REFERENCES 657
INDEX 670