Modelling Avalanche in DES-Like Ciphers
نویسنده
چکیده
In this paper, we examine the avalanche characteristics of private-key block ciphers constructed using a DES-like architecture. Avalanche is a desirable cryptographic property that is necessary to ensure that a small diierence between two plaintexts results in a seemingly random diierence between the two corresponding ciphertexts. In order to examine the behaviour of DES-like ciphers in relation to the avalanche property, a model of the cipher is developed which allows us to analyze the avalanche characteristics of the cipher for diierent cipher parameter values. In particular, the results suggest that large, symmetric S-boxes which satisfy the guaranteed avalanche property are eeective in combining eeciency and good avalanche characteristics of the cipher.
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