SAT-based cryptanalysis of modified versions of Feistel Network

It is well known that Feistel Network (FN) is the foundation of many symmetric ciphers used in practice. In this paper we present some remarks and experimental results on SAT based cryptanalysis of several modified versions of FN. We investigate different cryptographic functions used in FN schema for better understanding their properties from a security point of view. In our work we study the notions widely used in many ciphers: the xor function, bits rotations, permutations and S-boxes.