Content:
1. A brief history of cryptography
2. Rotary encryption machines and the first samples of Enigma
3. Enigma and its significance during the Second World War
4. The internal structure and principle of operation of Enigma
5. Decoding the Enigma code
1. A brief history of cryptography
1.1 Fundamentals and Principles of Cryptography
Cryptography is the science of creating and decrypting messages, the meaning of which is more or less secret from persons trying to intercept them. The message to be forwarded is called plaintext, while the message directly forwarded is called ciphertext. The main task of the encryption system is to ensure that it is impossible or extremely difficult to decrypt a message being forwarded without knowing the key - a special message encryption algorithm. The recipient of the message can easily decode it using this key.
1.2 The birth of cryptography
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