Confusion, Diffusion, and Substitution-Permutation Networks
This is an article in a series on Cryptography for the Everyday Developer. Follow along to learn the basics of modern cryptography and encryption. A block cipher is a type if cipher that combines an encryption/decryption algorithm that works on blocks of data with a mode of operation that details the techniques to process sequences of data blocks. While many different block cipher algorithms exist, they all share a common structural design: they apply a series of transformations — known as rounds — that iteratively manipulate the input data. These rounds consist of small, repeatable operations that gradually transform the plaintext into ciphertext. ...