

Articles
by
Z.A. Zukarnain 
Total Records (
2 ) for
Z.A. Zukarnain 





H.N. Jasem
,
Z.A. Zukarnain
,
M. Othman
and
S. Subramaniam


When using of the Internet increased dramatically; the congestion avoidance problem became even more important. The congestion is usually caused by the multiplexing for packets when the packets are at the bottleneck links. Efficiency and fairness are the important metrics in the performance of congestion avoidance mechanisms. And also all of the researches for the congestion avoidance algorithms, interest about this parameters metrics to evaluate the performance of the algorithms. This research studied the performance of the NewAdditive Increase Multiplicative Decrease (AIMD) algorithm as one of the core protocols for the TCP congestion avoidance and control mechanism. In addition, to evaluate the effect of using the AIMD algorithm after its development to measure the efficiency and fairness and find new enhancement results for our approach, which named as the NewAIMD algorithm. The NCTUns simulator is used to obtain the results after implementing the modifications to the mechanism. 




N. Jamil
,
R. Mahmod
,
M.R. Z`aba
,
N.I. Udzir
and
Z.A. Zukarnain


Hash function is an important cryptographic primitive used
in a wide range of applications, for example, for message authentication and
in digital signatures. MD 4/5 and SHA0/1/2 are examples of widely used hash
functions, but except for SHA2 (SHA224, 256, 384, 512), they were all broken
in 2005 after more than a decade of use. Since, then, the structure and components
of cryptographic hash functions have been studied and revisited extensively
by the cryptographic community. STITCH256 was introduced to overcome problems
faced by the MD and SHAfamily hash functions. STITCH256 employs the Balanced
Feistel network and its step operation runs in four parallel branches. The algorithm
was claimed to produce good diffusion and its outputs were claimed to be random.
To evaluate its suitability for such purposes, avalanche and empirical statisti
cal tests are commonly employed to show that there is empirical evidence supporting
the claims. In this study, we report on the studies that were conducted on the
1000 sample of 256 bit of output from STITCH256 algorithm. The studies include
the study of diffusion and statistical properties of STITCH256 using avalanche
test and nine statistical tests. The results suggest that the claims were true
where STITCH256 produces good avalanche effect, thus good diffusion property
and its outputs appear random. 





