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Substitution box is a significant and only nonlinear constituent of block cipher. S-box plays a central role in converting the intelligible message or plain text, into an enciphered format. Construction of strong S-boxes is an important area of interest for security experts. In this work, we develop a new method to evolve S-boxes with the help of coset graph for the action of P S L 2 , Z on projective line over the finite field GF (28), a special type of bijective map g and the symmetric group S256 The capability of the proposed S-boxes to mitigate cryptanalysis is investigated through various performance analyzing parameters. The outcomes of the comparison with the familiar S-boxes indicate that the working abilities of newly designed S-boxes are better than that of many of the well-known S-boxes. [ABSTRACT FROM AUTHOR]

Substitution box is a basic nonlinear component in data encryption. It converts the plain text into an enciphered format. The formation of cryptographically secure S-boxes is the most important task for cryptographers to ensure the security of the system. In this paper, we have introduced a novel method to increase the working capability of an S-box without demolishing its basic mathematical structure, that is, Eigen values, characteristic polynomial and determinant of the S-box/ 16 × 16 matrix. We considered Skipjack, Xyi, Prime, Jakimoski, Tang and Iqtadar S-boxes and reshuffled their rows/columns in such a way that they become cryptographically stronger. Algebraically, this can be accomplished by using appropriate permutations of the symmetric group S 16 over rows/columns of the S-boxes. The proposed technique is very constructive in enhancing the performance of S-boxes based on fundamental idea; bijection over the same set. The outcomes of different analyses demonstrated that the improved versions of S-boxes are more reliable than the original ones. [ABSTRACT FROM AUTHOR]

In the modern era of secure communication, it is important to create uncertainty in the original data in order to avoid unauthorized entities to extract or manipulate information. From simple methods such as permutations of original data to different mapping algorithms, the security of the ciphers rely on the substitution process. There are many types of components proposed in literature that are evolved by different methodologies and ideas. The prevailing ciphers use substitution boxes (S-boxes) to do this transformation process. In this work, we present a literature review of the design, construction, and analysis of the S-boxes used in block ciphers. The performance of S-boxes depends on the design and algebraic structure used for the construction and is contingent upon its ability to resist against cryptanalysis. We present the details of the S-box synthesis process and issues pertaining to creating resistance against various types of attacks, and highlight the consequences of a particular design methodology. In the infancy of the development of modern block ciphers, Shannon (Bell Syst. Tech. J. 28(4):656–715, 1949 ) presented the idea of encryption with the implementation of substitution-permutation network (SPN). In this process, the data is initially transformed by the substation process and then permuted that ends the first round supported by the secret key for this step. This substitution-permutation process is repeated several times to ensure reliability of encrypted data. The objective of using the substitution-permutation network is to create confusion between cipher text and secret key, and add diffusion in the plaintext. [ABSTRACT FROM AUTHOR]