In the SPN (Substitution-Permutation Network) structure, it is very important to design a diffusion layer to construct a secure block cipher against differential cryptanalysis and linear cryptanalysis. The purpose of this work is to prove that the SPN structure with a maximal diffusion layer provides a provable security against differential cryptanalysis and linear cryptanalysis in the sense th...

Deterministic symmetric encryption is widely used in many cryptographic applications. The security of deterministic block and stream ciphers is evaluated using cryptanalysis. Cryptanalysis is divided into two main categories: statistical cryptanalysis and algebraic cryptanalysis. Statistical cryptanalysis is a powerful tool for evaluating the security but it often requires a large number of pla...

This paper presents an approach for the comparative study on Data Encryption Standard (DES) using Differential Cryptanalysis and Linear cryptanalysis. In this paper, cipher text only attack is adopted and varieties of optimum keys are generated based on the cost function values. The goal of this paper is two fold. First we want to make a study about how evolutionary computation techniques can e...

The linear cryptanalysis proposed by Matsui is one of the most effective attacks on block ciphers, and he demonstrated an experimental cryptanalysis against DES at CRYPTO 1994. In this paper, we show how to optimize the linear cryptanalysis on modern microprocessors. Nowadays, there are two methods of implementing the linear cryptanalysis. Method 1 reduces the time complexity by reducing the nu...