英文原版书 部分目录 FOREWORD ix PREFACE xi ABOUT THE AUTHOR xvii CHAPTER 1 APERITIFS 1.1 The Lexicon of Cryptography 1 1.2 Cryptographic Systems 4 1.3 Cryptanalysis 4 1.4 Side Information 6 1.5 Thomas Jefferson and the M-94 6 1.6 Cryptography and History 7 1
A one-time pad system is the only system known that cannot be cracked by others. This system is also called the Vernam-cipher or perfect cipher. A message using this system cannot be broken because the encryption key is a random number and because t
