Performance Evaluation of QoS Provisioning Techniques for VoIP

Voice over Internet Protocol (VoIP) or IP Telephony application is one of the most promising services that can be implemented over the Internet. It is gaining more and more popularity each day due to its bandwidth-efficient implementation and the possibilities of integrating VoIP with other Web-based applications. However, the lack of quality of service (QoS) in the IP network could deter the development of VoIP. Being a real time application, voice traffic is intolerant of delays, loss, and jitter. Thus, some measure of QoS provision is necessary. In this paper two QoS mechanisms for VoIP, namely integrated services (IntServ) and differentiated services (DiffServ), have been simulated and analyzed. The main objective of these simulations is to measure and compare the performance of the network that uses VoIP application under different types of QoS provisioning techniques.