DLFSR is promising for enhancing the security of stream ciphers. However, good inviolability and statistical properties of the DLFSR generator are only achievable when the parameters of the switching algorithm are properly selected. This paper describes a new experimental method for choosing suitable parameters for the algorithm of switching the polynomial in DLFSR. This method was used to enhance the Grain-128 stream cipher. The randomness of the modified Grain was evaluated using the NIST suite, and the results are encouraging. The modified Grain was also compared to the original, and the results indicated that the modified algorithm outperforms the original in several tests. arabic 12 English 82
Fayrouz Aljadi, Ibrahim Almerhag, Fardous Eljadi(3-2019)

This paper is presenting a discrete-event simulator written in C++ for modeling and simulating Fat tree network-on-chip systems based on MPLS technique. The simulator contains main component that construct butterfly Fat tree structure and other components that generate suitable number of switches and IP nodes (cores). The designed switch consists of input ports, output ports, input/output link controller, multi-buffers, crossbar switch, routing and arbitration components and MPLS unit. The correctness and the efficiency of the MPLS based Fat network-on-chip system is measured against well-known wormhole+ virtual channels technique. The produced results are clearly demonstrated the efficiency of the MPLS technique for future NoC designs. arabic 45 English 189
Azeddien M. Sllame, Nagwa Abobaker Salama(2-2018)

in wireless networks, mobility is an important issue because Internet connectivity can only be effective if it is available during the movement of a node. To enhance mobility, the IEEE802.16e standard has set procedures to design wireless access systems to operate on the move without any disruption of services. The major difference between mobile WiMAX and fixed WiMAX is mobility support. However, speed and trajectory of nodes are unpredictable and can vary even in identical circumstances. In this paper mobile node trajectory is studied under different codecs schemes in order to evaluate the effect of node movement, towards or away from the base-station, on end to end delay, jitter, mean opinion score and throughput of a VoIP application. The results showed that trajectory inward improves network performance since mobile node gets closer to the base-station and hence signal is improved and less power is required. arabic 12 English 67
I. Almerhag, N. Aboalgasem(5-2017)