Abstract
To provide safe data communication, substitution boxes are employed in a variety of frameworks and cryptosystems. The acceptance of the AES encryption standard posed a challenge for security experts to develop sustainable substitution boxes utilizing various underlying techniques. It is because they are solely responsible to determine whether a cryptosystem is resistant to differential and linear cryptanalyses. The present study revealed a novel algebraic scheme of designing S-boxes with almost optimal characteristics to satisfy the robustness criteria. In literature, many S-box generation techniques based on Galois field of order 256 have been developed. Unlike existing Galois fields-based S-box methods, we utilized two Galois fields GF(2(7)) of order 128 with different structures for the construction of initial seed S-box, that forms a solid foundation for further optimization of the proposed technique. Then, for the merit of non-linearity optimization, we consider the action of the permutation group C(6888 )x C-4 x C-4 on initial S-box to enhance the proficiency of generated S-box. The quality of anticipated S-box is examined through various well-known performance parameters. The encouraging outcomes of standard performance analyses confirm that the generated S-box fulfills all the requirements for secure communication and image encryption.