TY - JFULL AU - Phyu Phyu Mar and Khin Maung Latt PY - 2008/1/ TI - New Analysis Methods on Strict Avalanche Criterion of S-Boxes T2 - International Journal of Mathematical and Computational Sciences SP - 898 EP - 903 VL - 2 SN - 1307-6892 UR - https://publications.waset.org/pdf/9381 PU - World Academy of Science, Engineering and Technology NX - Open Science Index 24, 2008 N2 - 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 each output bit with probability one half. If a function (cryptographic transformation) is complete, then each output bit depends on all of the input bits. Thus, if it were possible to find the simplest Boolean expression for each output bit in terms of the input bits, each of these expressions would have to contain all of the input bits if the function is complete. From some important properties of S-box, the most interesting property SAC (Strict Avalanche Criterion) is presented and to analyze this property three analysis methods are proposed. ER -