Proposed Hybrid Technique in Cryptanalysis of Cryptosystem Based on PSO and SA

Modern ciphers are one of the more difficult to break cipher systems because these high security, speed, non - propagation error and difficulty in breaking it. One most important weaknesses stream is a matching or correlation between output key-stream shift registers. This work considers new investigation methods for cryptanalysis using ciphertext only attack depending on Particle Swarm Optimization (PSO) automatic extraction key. It also introduces system based PSO with suggestion enhancement performance PSO, by Simulated Annealing (SA). Additionally, it presents comparison results that were obtained proposed technique, which called Modified (MPSO) classical GA. These algorithms can be used reducing number attempts trials key space, needed reach optimal solution (the exact initial setting Linear Feedback Shift Register (LFSR)),and increase speed search process find best solution. Based results, shown effective at finding MPSO method operates better compared term time accuracy. Well known attacked two soft computing as cases study, Geffe , Brȕer Shrinking systems.