The Algebra Properties of the S-Boxes of Several Block Ciphers

S-boxes bring nonlinearity to block ciphers and strengthen their cryptographic security. A detailed analysis of the cryptographic properties of S-boxes of several block ciphers, such as SMS4, AES, Camellia and SEED, are made in this paper. Some algebraic properties of boolean function of S-boxes such as balanceness, non-linearity, algebraic degree and walsh spectrums are well investigated. We reveal the advantages and disadvantages of those S-boxes used in SMS4, AES, Camellia and SEED as compared with each other.