Proposed Novel Architectures for Constructing Lightweight Dynamic S-Boxes

The Substitution Box (S-Box) is the only nonlinear component in block ciphers, playing a crucial role in ensuring the security of the cipher. Various methods for generating S-Boxes have been studied. In this paper, we propose the construction of lightweight dynamic S-Boxes based on controlled elements. The primary objective is to enhance the security of S-Boxes by identifying architectures that achieve high nonlinearity. The results show that the proposed architectures produce 4 × 4 dynamic S-Boxes with 4 bits control. These S-Boxes exhibit nonlinearity levels of up to 112, outperforming other S-Boxes of the same size, and meet other cryptographic criteria such as Strict Avalanche Criterion (SAC), Bit Independence Criterion (BIC), Linear Approximation Probability (LP), and Differential Approximation Probability (DP). Furthermore, the hardware implementation demonstrates that the resource usage remains compact, meeting the requirements for lightweight block cipher algorithms.