Non-Binary Cryptographic Functions for Symmetric Ciphers

This article explores the methods of mathematical description of regular nonlinearity replacement nodes, computing techniques for their design and evaluation of cryptographic indicators. Non-binary functions are also studied with the help of which we form regular nonlinearity replacement nodes. The results of a computational search for S-boxes using the proposed approach are presented. In terms of nonlinearity and autocorrelation, the formed replacement nodes are shown to have improved properties.