NUST Institutions Library Catalogue

Chapter 0 Reader’s Guide 1 0.1 Outline of This Book 2 0.2 A Roadmap for Readers and Instructors 2 0.3 Internet and Web Resources 4 0.4 Standards 5 Chapter 1 Overview 7 1.1 Computer Security Concepts 9 1.2 The OSI Security Architecture 14 1.3 Security Attacks 15 1.4 Security Services 19 1.5 Security Mechanisms 23 1.6 A Model for Network Security 25 1.7 Recommended Reading and Web Sites 27 1.8 Key Terms, Review Questions, and Problems 29 PART ONE SYMMETRIC CIPHERS 31 Chapter 2 Classical Encryption Techniques 31 2.1 Symmetric Cipher Model 33 2.2 Substitution Techniques 38 2.3 Transposition Techniques 53 2.4 Rotor Machines 55 2.5 Steganography 57 2.6 Recommended Reading and Web Sites 59 2.7 Key Terms, Review Questions, and Problems 60 Chapter 3 Block Ciphers and the Data Encryption Standard 66 3.1 Block Cipher Principles 68 3.2 The Data Encryption Standard (DES) 77 3.3 A DES Example 85 3.4 The Strength of DES 88 3.5 Differential and Linear Cryptanalysis 89 3.6 Block Cipher Design Principles 92 3.7 Recommended Reading and Web Site 96 3.8 Key Terms, Review Questions, and Problems 97 Chapter 4 Basic Concepts in Number Theory and Finite Fields 101 4.1 Divisibility and the Division Algorithm 103 4.2 The Euclidean Algorithm 105 v vi CONTENTS 4.3 Modular Arithmetic 108 4.4 Groups, Rings, and Fields 116 4.5 Finite Fields of the Form GF(p) 120 4.6 Polynomial Arithmetic 122 4.7 Finite Fields of the Form GF(2n) 129 4.8 Recommended Reading and Web Sites 141 4.9 Key Terms, Review Questions, and Problems 141 Appendix 4A The Meaning of mod 144 Chapter 5 Advanced Encryption Standard 47 5.1 The Origins AES 148 5.2 AES Structure 150 5.3 AES Round Functions 155 5.4 AES Key Expansion 166 5.5 An AES Example 169 5.6 AES Implementation 174 5.7 Recommended Reading and Web Sites 178 5.8 Key Terms, Review Questions, and Problems 179 Appendix 5A Polynomials with Coefficients in GF(28) 180 Appendix 5B Simplified AES 183 Chapter 6 Block Cipher Operation 192 6.1 Multiple Encryption and Triple DES 193 6.2 Electronic Codebook Mode 198 6.3 Cipher Block Chaining Mode 201 6.4 Cipher Feedback Mode 203 6.5 Output Feedback Mode 205 6.6 Counter Mode 206 6.7 XTS Mode for Block-Oriented Storage Devices 210 6.8 Recommended Web Site 214 6.9 Key Terms, Review Questions, and Problems 214 Chapter 7 Pseudorandom Number Generation and Stream Ciphers 218 7.1 Principles of Pseudorandom Number Generation 219 7.2 Pseudorandom Number Generators 226 7.3 Pseudorandom Number Generation Using a Block Cipher 229 7.4 Stream Ciphers 232 7.5 RC4 234 7.6 True Random Numbers 237 7.7 Recommended Reading 238 7.8 Key Terms, Review Questions, and Problems 239 PART TWO ASYMMETRIC CIPHERS 243 Chapter 8 More Number Theory 243 8.1 Prime Numbers 245 8.2 Fermat’s and Euler’s Theorems 248 8.3 Testing for Primality 251 8.4 The Chinese Remainder Theorem 254