Issue No. 09 - September (1995 vol. 44)
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/12.464391
<p><it>Abstract</it>—This paper develops analytical models for the avalanche characteristics of a class of block ciphers usually referred to as substitution-permutation encryption networks or SPNs. An SPN is considered to display good avalanche characteristics if a one bit change in the plaintext input is expected to result in close to half the ciphertext output bits changing. Good avalanche characteristics are important to ensure that a cipher is not susceptible to statistical attacks and the strength of an SPN’s avalanche characteristics may be considered as a measure of the randomness of the ciphertext. The results presented in this paper demonstrate that the avalanche behavior of encryption networks can be improved by using larger S-boxes. As well, it is shown that increasing the diffusion properties of the S-boxes or replacing the permutations by diffusive linear transformations is effective in improving the network avalanche characteristics.</p>
Avalanche, block ciphers, cryptography, S-boxes, substitution-permutation encryption networks.
H. M. Heys and S. E. Tavares, "Avalanche Characteristics of Substitution-Permutation Encryption Networks," in IEEE Transactions on Computers, vol. 44, no. , pp. 1131-1139, 1995.