Cryptanalysis of Two-Round DES Using Genetic Algorithms

摘要

Cryptanalysis with genetic algorithm has attracted much interest in recent years. This paper presents an approach for the cryptanalysis of two-round DES based on genetic algorithm. However, cryptanalysis of two-round DES using genetic algorithm is usually a difficult task. In this paper, we adopt known plaintext attack and produce a variety of optimum keys based on fitness function. Furthermore, we count every bit of optimal keys one by one, and find some valuable bits, which generate a significant deviation from the other observed bits. Finally, the 56-bit key is successfully gained without searching the whole search space. The experimental result indicates that this is a promising method and can be adopted to handle other complex block ciphers.