This paper presents an approach to cryptanalysis of RSA cryptosystem based on the application of genetic algorithm. The search utilizes the idea of timing attack as computation time information may leak due to different modular operations throughout the RSA encoding. This approach suggests a speed up process, aiming at reducing the required number of plaintext-ciphertext samples needed for a successful timing attack. The proposed notion of timing attack outlined in this work with its preliminary implementation, have given encouraging results on RSA cryptosystem samples. Further work carried on to implement the idea of genetic algorithm technique to practical RSA system has demonstrated encouraging results.

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[12] Spillman R., Janssen M., Nelson B., and Kepner M., “Use of a Genetic Algorithm in the Cryptanalysis of Simple Substitution Cipher,” Cryptologia, vol. 17, no.1, 1993. Hamza Ali BSc in physics from Basrah University 1968, MSc in electronics from University of London 1973 and PhD in computer engineering from University of London, 1977. Previously he worked in Basrah University, Iraq, Shatt Alarab University College, Iraq, Aizu University, Japan, and currently associate professor at the Computer Science Department, Zarka Private University, Jordan. His research interest includes computer data and networks security, authentication and digital signature, recognition of Arabic script and neural networks. Mikdam Al-Salami obtained his MSc and BSc in computer science from Basrah University, Iraq, 1996 and 1999, respectively. Previously he worked at Ar-Rafidain University College, Iraq. Currently, he is a lecturer at the Computer Science Department, Zarka Private University, Jordan. His research areas include cryptography in computer systems, authentication and management of data protection.