NOVA scienceNOW's "Can Science Stop Crime" introduced you to Tadayoshi Kohno, a University of Washington computer scientist who's made it his mission to take over networked machines, identifying ...

1. Introduction -- 2. From Julius Caesar to simple substitution -- 3. Polyalphabetic systems -- 4. Jigsaw ciphers -- 5. Two-letter ciphers -- 6. Codes -- 7. Ciphers for spies -- 8. Producing random ...

Introduction to ciphers and substitution. Alice and Bob and Carl and Julius: terminology and Caesar Cipher ; The key to the matter: generalizing the Caesar Cipher ; Multiplicative ciphers ; Affine ...