Random S-boxes in Symmetric Ciphers

This description is about a new 256-bit block symmetric substitution-permutation cipher, called a managed substitution cipher. This is a cipher with single-layer permutated transformations in each cycle. The management of substituted transformations occur by including them in a chain so that the output value of the previous SL transform is fed to the input of the current fortified 32-bit substituted transformation (SL conversion) along with the current value of the input data block through the adder for modulo 2. It is shown that such construction of cycled function allows to use random substitutions without any selection in a cipher while not reducing its strength.