Abstract: The analysis of performance criteria for different
cryptographic algorithms has increasingly been concerned in the
last few years and that is because the majority of life applications
need cryptographic algorithms to be involved in their structure to
provide security for these applications such as banking services,
e-government and online applications [1]. In this paper, the
analytic study is executed on the most specific popular
cryptographic algorithm which is “AES” technique [2][3] in
order to research the impact of utilizing different models which
are named “modes” on the behavior of “AES” technique and
hence increases the cryptographic strength of “AES” technique.
The criteria utilized to aid in judging on the influence of modes
on the behavior of “AES” technique are enciphering time,
throughput and strict avalanche criteria (SAC). Such influence
has been clarified and presented through providing comparative
analysis among modes of operation according to previously
mentioned parameters. First the analytic study is proposed
utilizing the traditional substitution box formula in constructing
AES technique then an enhanced version of substitution box
equation is included in AES technique to provide more complex
and securing substitution box in constructing AES algorithm so
as to measure the impact of changing the formula of substitution
box on the behavior of AES technique and its cryptographic
capabilities. Finally, the results of executing the modes on the
behavior of AES technique in case of utilizing the traditional sbox
and the enhanced version of s-box are listed in terms of the
previously mentioned criteria enciphering time, throughput and
(SAC) and consequently we come up with the conclusion that
SAC parameter is the only criterion that shows the impact of
utilizing different modes on the behavior of AES technique but
the enciphering time and throughput has no role in showing the
influence of utilizing distinctive modes on the behavior of AES
technique regardless of changing the substitution box equation
utilized in “AES” technique. |
