Title: PERFORMANCE EFFICIENCY OF MODIFIED AES ALGORITHM USING MULTIPLE S-BOXES

Issue Number: Vol. 5, No. 1
Year of Publication: March - 2015
Page Numbers: 1-9
Authors: Felicisimo V. Wenceslao, Jr.
Journal Name: International Journal of New Computer Architectures and their Applications (IJNCAA)
- Hong Kong
DOI:  http://dx.doi.org/10.17781/P001620

Abstract:


In our previous paper, we modified the Advance Encryption System (AES) algorithm by proposing to use multiple substitution boxes (S-Boxes). While many studies have been conducted specifically on modifying the S-box, these studies were made to replace the Rijndael S-box in the AES cipher. Our version of the AES algorithm used two substitution boxes where the first S-box is the Rijndael S-box and was used as is. The second S-box was constructed by performing an XOR operation and affine transformation. Furthermore, the second S-Box replaced the MixColumns operation within the internal rounds in the cipher. This paper aims to determine the performance efficiency of the modified AES algorithm using multiple S-Boxes. Based on the result of the experiments, it was found out that the modified AES algorithm using multiple S-Boxes has an achieved execution time performance efficiency of 22.986% for encryption and 109.76% for decryption processes. However, when tested using the avalanche effect, the changes in the output bits were below the minimum expected rate at 24.219% and 19.531% respectively.