TY - JOUR AU - Salim A.Abbas, AU - Mohamed H. Albawi, PY - 2020/09/20 Y2 - 2024/03/29 TI - USEs OF GA, PSO and MPSO TO BREAK TRANSPOSITION CIPHER SYSTEM: comparative study JF - مجلة المستنصرية للعلوم والتربية JA - Mustansiriyah.J.Sci.Edu VL - 17 IS - 5 SE - DO - UR - https://edumag.uomustansiriyah.edu.iq/index.php/mjse/article/view/68 SP - 207-226 AB - <p>GA is an adjustable search method that has the ability for search in<br>smart way to find the best solution and trying to reduce the time that required<br>for obtaining the optimal solution. Particle Swarm Optimization (PSO)<br>algorithm emulate the behavior of a swarm of fish and bird flocks. It's a<br>heuristic global optimization method which can be implemented and<br>applying to solve various optimization problems. The most attractive of using<br>PSO is that it has a fast convergence than the other global optimization<br>methods. Modify PSO (MPSO) is a relatively new approach to attacks<br>transposition cipher which it depends on using multi swarms rather than<br>single swarm and allowing the particles in all swarms to exchange<br>information between them in order to obtains the best solution from all<br>swarms.<br>This research focuses on use GA, PSO and MPSO to cryptanalyze<br>transposition cipher based on a new tools to determine the fitness function by<br>calculating the Diagram(DG), Trigram(TG) and Quadgram (QG) frequency<br>of letters. It is shown that such algorithms can be used to reduce the number<br>of trails which are needed to determined the initial states of the attacked<br>systems using ciphertext only attack.<br>Experimental results show the successful applications of GA, PSO and<br>MPSO in cryptanalysis of transposition cipher system. Also, the experimental<br>results indicate that the MPSO is more powerful than the other techniques in<br>cryptanalysis transposition depending on the accuracy of results.</p> ER -