Cryptanalysis of the RC4 Stream Cipher using Evolutionary ...

makes this paper relevant to the research proposed is that the problem is encoded as a
permutation problem.
As a result, the authors examine several ordered crossover (OX)
methods including partially mapped crossover (PMX) and edge recombination crossover
(ER) as well as a method called cycle crossover (CX) that was not chosen for this task
due to its larger computational needs over the other methods proposed. The authors also
experimented with both the swap mutation method (SwM) and the inversion mutation
method (InvM). The paper ultimately used a method created by the authors which claimed
to be superior to the standard OX methods previously stated but since no algorithm for
this method was stated, it cannot be replicated or utilized in this Thesis.
In Brown et al. the use of a genetic algorithm was used to attack a substitution permutation
network. While the study was intended to find weak keys, it was later noted that a
GA would be a good tool to attack the scheme [8]. The paper is important to this research
as it used SwM to attack the network and it was also a method proposed to attacking other
relevant crypto systems such as AES and 3DES.
3.2.2 Cryptanalysis Using Particle Swarm Optimization
The use of PSOs in cryptanalysis is relatively new to the field but it seems to be showing
promise as a successful avenue of thought. In 2012 Valarmathi et al. attacked a simplified
version of the Advanced Encryption Standard (S-AES). The research yielded a great amount
of success in the recovery of the key used to encrypt data. One main observation of this
paper was that utilizing this method, as the amount of ciphertext used increased, the
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