Proposed A Permutation and Substitution Methods of Serpent Block Cipher
DOI:
https://doi.org/10.30526/32.2.2120Keywords:
Serpent block cipher, initial and final permutation, substitutions boxes, key generation, logistic chaos map, standard chaos map.Abstract
Block cipher technique is one of cryptography techniques to encrypt data block by block. The Serpent is one of AES candidates. It encrypts a 128-bit block by using 32 rounds of a similar calculation utilizing permutations and substitutions. Since the permutations and substitutions of it are static. Then this paper proposes dynamic methods for permutation, substitution and key generation based on chaotic maps to get more security. The proposed methods are analyzed and the results showed that they were able to exceed the weakness resulting from the use of static permutations and substitutions boxes in the original algorithm and also can reduce number of rounds and time usage compared with a classical Serpent block cipher algorithm