Abstract
Genetic algorithms (GAs) are a class of optimization algorithms. GAs attempt to solve problems through modeling a simplified version of genetic processes. There are many problems for which a GA approach is useful. It is, however, undetermined if cryptanalysis is such a problem. Therefore, this work explores the use of GAs in cryptography. Both traditional cryptanalysis and GA-based methods are implemented in software. The results are then compared using the metrics of elapsed time and percentage of successful decryptions. A determination is made for each cipher under consideration as to the validity of the GA-based approaches found in the literature. In general, these GA-based approaches are typical of the field. Of the genetic algorithm attacks found in the literature, totaling twelve, seven were re-implemented. Of these seven, only three achieved any success. The successful attacks were those on the transposition and permutation ciphers by Matthews [20], Clark [4], and Griindlingh and Van Vuuren [13], respectively. These attacks were further investigated in an attempt to improve or extend their success. Unfortunately, this attempt was unsuccessful, as was the attempt to apply the Clark [4] attack to the monoalphabetic substitution cipher and achieve the same or indeed any level of success. Overall, the standard fitness equation genetic algorithm approach, and the scoreboard variant thereof, are not worth the extra effort involved. Traditional cryptanalysis methods are more successful, and easier to implement. While a traditional method takes more time, a faster unsuccessful attack is worthless. The failure of the genetic algorithm approach indicates that supplementary research into traditional cryptanalysis methods may be more useful and valuable than additional modification of GA-based approaches.
Library of Congress Subject Headings
Cryptography--Research; Genetic algorithms--Research; Data encryption (Computer science)--Research
Publication Date
7-1-2004
Document Type
Thesis
Department, Program, or Center
Computer Engineering (KGCOE)
Advisor
Shaaban, Muhammad
Advisor/Committee Member
Radziszowski, Stanislaw
Advisor/Committee Member
Yang, Shanchieh
Recommended Citation
Delman, Bethany, "Genetic algorithms in cryptography" (2004). Thesis. Rochester Institute of Technology. Accessed from
https://repository.rit.edu/theses/5456
Supporting Program Files
Campus
RIT – Main Campus
Comments
Note: imported from RIT’s Digital Media Library running on DSpace to RIT Scholar Works in December 2013. Physical copy available from RIT's Wallace Library at QA268 .D45 2004