Cipher Applets

Shift Cipher - add a constant to each plaintext character

Affine Cipher - multiply each plaintext character by one constant, then add another constant

Vigenere Cipher - add each plaintext character to the next character in the repeated key

Simple Substitution Cipher - each letter of the alphabet is replaced by some other letter, like a cryptogram in the newspaper

Feistel (a simplified DES) - a block cipher: XOR half of the block with a function of the other half, and repeat

RC4 - a simple stream cipher used in SSL (which protects HTTPS secure web pages)

RC4 encryption
Probability distribution after key setup
Dependency on the first few bytes of the key

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