Data Privacy and Security.

By David Salomon. Published by Springer Verlag May 2003. ISBN 0-387-00311-8. LCCN QA76.9.A25S65 2003. xii+470 pages.

A BibTeX style file and an Errata list are available.

Both classical (paper and pen) and modern (computer-based) cryptographical methods are described. A large part of the book is devoted to steganography, the art and science of hiding information. Again, older methods as well as modern, computer-based methods are included.

Table of Contents

Preface vii
Introduction 1

Part I Data Encryption 19

1 Monoalphabetic Substitution Ciphers 21
2 Transposition Ciphers 39
3 Polyalphabetic Substitution Ciphers 59
4 Random Numbers 91
5 The Enigma 107
6 Stream Ciphers 131
7 Block Ciphers 155
8 Public-Key Cryptography 195
9 Quantum Cryptography 235

Part II Data Hiding 243

10 Data Hiding in Text 245
11 Data Hiding in Images 269
12 Data Hiding: Other Methods 339

Part III Essential Resources 367

A Convolution 369
B Hashing 377
C Cyclic Redundancy Codes 383
D Galois Fields 387

Answers to Exercises 401
Cryptography Timeline 419
Glossary 429
Bibliography 441
Index 453

Extra Material

This section contains extra material added by the author from time to time. These documents add new material or shed new light on material already included in the book.

1. Secure Socket Layer (SSL) is an important protocol used for secure communications on the Internet. Private information should be encrypted before it is transmitted on the Internet. The encryption algorithm is known and security is obtained by the key. Each data transmission uses a different key, selected at random, and the SSL protocol is applied to securely communicate the key over an unsecure communications line. This short document (PDF, 9 pages, 308K) explains the process in detail (thanks to Stephen Fuld for corrections). It also includes a description of the MD5 hashing algorithm.

2. The Enigma cipher machine and the breaking of its code are described in the book in detail. Recent news about advanced Enigma codes were published in on 2 March 2006 and are available here, for the readers' convenience, in PDF format.

3. Hedy Lamarr and the invention of spread spectrum technology are mentioned on page 297. Richard Rhodes has written a nice, detailed book titled Hedy's Folly: The Life and Breakthrough Inventions of Hedy Lamarr, the Most Beautiful Woman in the World (published by Doubleday in November 2011). The book describes the lives of Hedy and her coinventor George Antheil, as well as the background and principles of their invention.

4. (May 2017) Page 257 describes a simple proposal for semantic steganography. A somewhat similar approach, proposed and implemented in Python by Mok-Kong Shen, has recently come to my attention. It is freely available here.

5. Appendix A discusses the term "convolution." A better explanation, with examples, of this important term can be found here.

Review (SIGACT News vol. 36, #2, 2005)

Overall, Data Privacy and Security is a handy and concise volume on cryptography and steganography. While the more advanced reader will find alternative references - such as Bruce Schneier's Applied Cryptography - more satisfying, this book is clearly written and self contained. All the important cryptosystems are covered, and the discussion of recent developments, including Rijndael and quantum cryptography, is welcome.

Last Updated 5 May 2017.