Caesar-Cipher

A basic encryption method that maps every letter to another by shifting each one by an offset.

Encryption: E: \mathbb{Z_{26} \times Z_{26}} \to Z_{26} is defined as E_{K}(M) = (M+K) mod 26

Decryption: E^{-1}: \mathbb{Z_{26} \times Z_{26}} \to Z_{26} is defined as E_{K}^{-1}(C) = (C-K) mod 26

This encryption encryption method uses a set of 26 permutations that are iterative applied to every letter of M or C.

With K = 13 we get E_{13} = E^{-1}_{13} since (13+13 \bmod 26) = 0 = 13-13.