Performance Analysis of the Modified Vigenere Algorithm to Secure Data
Abstract— The Vigenere algorithm is simple but considered unbreakable. However, the repeating key is its
weakness and is still widely developed by researchers to increase the key length of the algorithm. This study
aims to test and evaluate the security performance of the modified Vigenere cipher algorithm to address its
vulnerability. The results show that the modified algorithm effectively overcomes Kasiski attack. Moreover,
the frequency analysis test shows that the frequency of occurrence of alphabetic letters I and O obtained 9.0
curve value whereas M and V have 6.7 curve value. This frequency analysis result indicates that the
enhanced Vigenere algorithm has reduced the effect of cryptanalysis. The modified algorithm has also passed
the randomness ciphertext test when the frequency (monobit) test was performed. The result shows that the
p-value computed is 0.841 which is higher than 0.01; hence, the generated ciphertext is considered random.
Index Terms— key generation, security evaluation, Vigenere algorithm
Daniel A. Neri, Ruji P. Medina
Technological Institute of the Philippines, PHILIPPINES
Ariel M. Sison
Emilio Aguinaldo College, PHILIPPINES
Cite: Daniel A. Neri, Ariel M. Sison, Ruji P. Medina, "Performance Analysis of the Modified Vigenere Algorithm to Secure Data," Proceedings of 2019 the 9th International Workshop on Computer Science and Engineering, pp. 789-794, Hong Kong, 15-17 June, 2019.