Alternative of Strict Avalanche Criterion Test on Block Cipher Using Fisher’s Method
Andriani Adi Lestari, Anang Kurnia, Farit Mochamad Afendi · International Journal of Applied Mathematics & Statistics/International journal of applied mathematics and statistics · 2015
Block cipher was one of the cryptography techniques used to provide information security, especially confidentiality. Strict avalanche criterion (SAC) was a desirable characteristic of block cipher. If a block cipher satisfies strict avalanche criterion, then each output bit should change with a probability of one-half whenever a single input bit was complemented. Avalanche matrix was constructed to ascertain whether a block cipher satisfied SAC. A block cipher satisfies strict avalanche criterion if each entry of avalanche matrix was equal to one-half. Dawson proposed statistically based methods for determining whether a block cipher satisfies SAC. In this paper, we proposed an alternative statistical test to test the hypothesis that a block cipher satisfies SAC. The approach used to develop the alternative test statistic was by testing equality of each entry of the mean of avalanche matrices to one-half and then combined using Fisher’s method. That statistic was minus two times sum of the logarithm of p-value, where the p-value was tail area probabilities of z-statistic from each entry of the mean of avalanche matrices. The simulation showed that the power of the alternative SAC test was higher than the Dawson SAC test.