Discover the science of cryptology! This book is a complete introduction to codes, ciphers and secret messages. You will discover: - How codes and ciphers work - How secret messages can be concealed in apparently innocuous messages (steganography) - How codebreakers and cryptanalysts break codes and ciphers - Many examples of how codes and ciphers have changed history and continue to shape the world to this day
Enigma (see Chapter 8) was an electromechanical machine that enciphered and deciphered messages. It was used by Germany in the interwar years and during World War II. The general principle of Enigma was that messages would be enciphered by the sender using the machine and then transmitted by Morse code over the radio as encoded ciphertext. The recipient would transcribe the Morse code, and then enter it into their own Enigma machine to decipher the message. The radio signals could of course be intercepted by the German’s enemies, but the Germans (wrongly) believed that their messages were secure, since they did not think that Allied cryptanalysts would be able to break the cipher.
Introduction: What are Codes, Ciphers and Steganography?
Chapter 1: Codes used for Communication Flag Code Semaphore Code Polybius Square Optical Telegraph Codes Electrical Telegraph Codes - International Morse Code - Baudot Code - Murray Code and ITA 2 - ASCII Computer Codes
Chapter 2: Caesar Ciphers Using a Caesar Cipher Variations of the Caesar Cipher - ROT13 - ROT5 - ROT18 - ROT47 - Avgad and Albam Breaking Caesar Ciphers
Chapter 8: Enigma The Enigma Machine How Enigma was Broken - Early British Efforts - Polish Cipher Bureau - Polish Cooperation with the Western Allies - PC Bruno - Cadix - British Efforts Against Italian Naval Enigma - The British Focus on Cribs - British and American Bombes - German Suspicions
Chapter 9: Perfect Ciphers Vernam Cipher One-Time Pads Difficulties of Implementing a Perfect Cipher - Protecting the Key - Not Reusing the Key - Randomness in the Key - The Equipment Used Must Be Secure Lorenz Cipher - Cryptanalysis of the Lorenz Cipher