A highly nonlinear S-box based on a fractional linear transformation View Article: PubMed Central - PubMed ABSTRACTWe study the structure of an S-box based on a fractional linear transformation applied on the Galois field \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$GF(2^{8})$$\end{document}GF(28). The algorithm followed is very simple and yields an S-box with a very high ability to create confusion in the data. The cryptographic strength of the new S-box is critically analyzed by studying the properties of S-box such as nonlinearity, strict avalanche, bit independence, linear approximation probability and differential approximation probability. We also apply majority logic criterion to determine the effectiveness of our proposed S-box in image encryption applications. No MeSH data available. © Copyright Policy - OpenAccess Related In: Results  -  Collection License getmorefigures.php?uid=PMC5037109&req=5 .flowplayer { width: px; height: px; } Fig4: SAC of different S-boxes Mentions: For any cryptographic design, when we change the input bits, the performance of the output bits is examined by this criterion. It is desired that a change in a single input bit must cause changes in half of the output bits. In other words a function is said to satisfy SAC if for a change in an input bit the probability of change in the output bit is 1/2. It is clear from the results shown in Table 4 and Fig. 4 that our S-box satisfies the requirements of this criterion.Fig. 4

A highly nonlinear S-box based on a fractional linear transformation
Related In: Results  -  Collection

We study the structure of an S-box based on a fractional linear transformation applied on the Galois field \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$GF(2^{8})$$\end{document}GF(28). The algorithm followed is very simple and yields an S-box with a very high ability to create confusion in the data. The cryptographic strength of the new S-box is critically analyzed by studying the properties of S-box such as nonlinearity, strict avalanche, bit independence, linear approximation probability&nbsp;and differential approximation probability. We also apply majority logic criterion to determine the effectiveness of our proposed S-box in image encryption applications.