This paper describes a comparative study of the performance of VoIP over wireless networks using OPNET tool. The simulation study is completed by running VoIP application in different network scenarios with IEEE 802.16 (UGS, ertPS) and IEEE 802.11 (b, g) with best effort service and interactive service The result clearly illustrated that the WiMax type ertPS has the best performance among all tested cases
Azeddien M. Sllame, Hana Soso, Mona Aown, Lamya Abdelmajeed(9-2016)

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)

Network availability is a key consideration in disaster planning, but it also has critical impacts on everyday life and work. For organizations, network downtime or sluggishness equates to business downtime, at considerable cost to organizations through inefficiency, lost sales, lack of critical data for decisions, and other harmful effects. First hop redundancy protocols (FHRP) are an essential tool for improving the availability of IP networks. In this paper, we evaluate the three particular protocols of FHRPs, namely the Hot Standby Router Protocol (HSRPv6), Virtual Router Redundancy Protocol (VRRPv3), and Gateway Load Balancing (GLBPv6) using GNS3 tools. The First Hop Redundancy Protocols have been implemented, tested, optimized, and compared to one another in terms of CPU Utilization, Traffic flow, packet loss and convergence time. The comparison indicates which protocol is best in which scenario and which is best among the three protocols.
Mahmud Mansour, Mohamed Alamin Alqomati, Mohmed K. Al-said(3-2022)