Strict Criterion of Graduation

Strict key avalanche criterion

A block cipher, such as the DES cipher, is used to encrypt binary plaintext in discrete blocks of length n using a key of length m, to form ciphertext blocks of length n. A block cipher is said to satisfy the strict key avalanche criterion if a one bit change in the key causes on the average one half of the ciphertext bit positions to change. In this paper the importance of the strict key avala...

Strict avalanche criterion over finite fields

Boolean functions on GF (2) which satisfy the Strict Avalanche Criterion (SAC) play an important role in the art of information security. In this paper, we extend the conception SAC to finite fields GF (p). A necessary and sufficient condition is given by using spectral analysis. Also, based on an interesting permutation polynomial theorem, we prove various facts about (n − 1)-th order SAC func...

The strict avalanche criterion randomness test

A new statistical test for randomness, the strict avalanche criterion (SAC) test, is presented, together with its results over some well-known generators in the literature. These results are analyzed and some possible applications of the test, as for measuring the strength of cryptographic primitives including block ciphers, stream ciphers and pseudorandom number generators, especially during t...

New Analysis Methods on Strict Avalanche Criterion of S-Boxes

S-boxes (Substitution boxes) are keystones of modern symmetric cryptosystems (block ciphers, as well as stream ciphers). S-boxes bring nonlinearity to cryptosystems and strengthen their cryptographic security. They are used for confusion in data security An S-box satisfies the strict avalanche criterion (SAC), if and only if for any single input bit of the S-box, the inversion of it changes eac...

A lower bound on the number of functions satisfying the strict avalanche criterion