Development and Implementation of the Genetic Algorithm for Encryption Systems Cryptanalysis Using a Cardan Grille

Nowadays the problem of transferring the information via the Internet or with digital electronic devices is as crucial as it has always been. With the rapid development of the computers, the complexity of encryption methods will only grow, ensuring the confidentiality of storing and transferring the information. However, at the same time, new improved methods of breaking these codes are developed by different specialists. The main goal of this paper is to create a genetic algorithm for cryptanalysis of encryption systems using the Cardan grille and develop a program product, using these algorithms. Genetic algorithms are rarely used in the cryptanalysis field, thus, creating another goal of this research – to find, whether or not the genetic algorithms can be used there successfully. As a result, two program modules were created: the encryption system, which uses the Cardan grille method as well as a method of generating new proper grids, and a decryption system, where the developed genetic algorithm was implemented. Besides that, there was developed an algorithm for counting bigrams in a text. We have not only managed to successfully encrypt the given text with the Cardan grille method and then decrypt it, using the genetic algorithm, but also managed to prove the credibility of using the genetic algorithms in breaking simple symmetric ciphers like the Cardan grille. This work consists of three chapters, 35 pictures, four formulas, two tables and two appendices.