International Association
for Cryptologic Research

The Cryptographics Algorithms AES and Twofish guarantee a high diffusion

with the use of fixed MDS matrices of size 4 x 4. In this article variations to the Cryptographics Algorithms AES and Twofish are made. They allow that the process of cipher-decipher come true with MDS matrices selected randomly from an algorithm that obtaining an MDS matrix of set of all the MDS matrices possible. A new Schedule of key with a high diffusion is designed for the Algorithm Cryptographic AES. Besides it is proposed a new S-box that he varies in function of the key.