Faster variants of the MESH block ciphers

Abstract

This paper describes new variants of the MESH block ciphers, that use the same group operations of the IDEA cipher but operate on 8-bit words, and are estimated to be faster than the AES on 8-bit processors. These results corroborate the high flexibility of the MESH cipher design, demonstrating their high adaptability to 8-bit smart card processors, such as the 8051. All the design features of the original 16-bit word-oriented MESH ciphers were preserved for the 8-bit variants: complete diffusion in a single round; MA-boxes alternating modular addition and multiplication; asymmetric key-mixing layers for odd and even rounds; new key schedule algorithms with fast key avalanche; the same computational framework holds for encryption and decryption. Preliminary Square and algebraic attack results are described, and resistance to other modern cryptanalytic techniques is also expected. © Springer-Verlag 2004.