Cryptanalysis of Mono-Alphabetic Substitution Ciphers using Genetic Algorithms and Simulated Annealing

  • Shalini Jain Marathwada Institute of Technology, Dr. Babasaheb Ambedkar Marathwada University, India
  • Nalin Chhibber University of Waterloo, Ontario, Canada
  • Sweta Kandi Marathwada Institute of Technology, Dr. Babasaheb Ambedkar Marathwada University, India
Keywords: Cryptanalysis, Mono-Alphabetic Substitution Cipher, Genetic Algorithms, Simulated Annealing


In this paper, we intend to apply the principles of genetic algorithms along with simulated annealing to cryptanalyze a mono-alphabetic substitution cipher. The type of attack used for cryptanalysis is a ciphertext-only attack in which we don’t know any plaintext. In genetic algorithms and simulated annealing, for ciphertext-only attack, we need to have the solution space or any method to match the decrypted text to the language text. However, the challenge is to implement the project while maintaining computational efficiency and a high degree of security. We carry out three attacks, the first of which uses genetic algorithms alone, the second which uses simulated annealing alone and the third which uses a combination of genetic algorithms and simulated annealing.


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