Virtual Private Network (VPN) technology provides a way of protecting information being transmitted over the Internet, by allowing users to establish a virtual private “tunnel” to securely enter an internal network, accessing resources, data and communications via an insecure network such as the Internet. A VPN is a communications environment in which access is controlled to permit peer connections only within a defined community of interest, and is constructed though some form of partitioning of a common underlying communications medium, where this underlying communications medium provides services to the network on a nonexclusive basis. arabic 6 English 50
Mariam Abojela Msaad, Amer R. Zerek, Hana H. saleh(1-2012)

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)

This paper describes the place of MPLS in current state-of-the-art networking as a quality of service means through performing performance analysis of VoIP and video conferencing applications by comparing the effect of different protocols (OSPF, IS-IS, EIRGP) and the effect of various queuing techniques (PQ, WFQ, MWRR) in order to find the good combination of MPLS, routing, and queuing type that provides efficient suitable quality of service levels. The obtained results illustrate a competent combination of MPLS with queuing discipline, and routing could be achieved for each application, such as MPLS and EIGRP with WFQ queuing is an efficient arrangement for video conferencing application
Azeddien M. Sllame, Reema A. Saad, Mariam Abojella Msaad(5-2021)