Techniques for performance improvement of VoIP applications

In order to effectively compete in today´s telecommunication market, service providers and enterprises are turning towards voice over IP (VoIP) technology. Initially, the goal of using VoIP in enterprises was a better utilisation of internal packet networks and avoiding long-distance toll charges. On the other side service providers need to rollout new revenue generating services quickly. There are many compelling reasons to migrate voice traffic to IP networks, but certain problems must be solved first. This paper introduces important concepts surrounding the performance of VoIP applications in corporate networks and in the Internet. We explain the problem of end-to-end delays, delay jitter, packet reordering and frame erasures and also emerging techniques for solving those problems. This paper focuses on the performance of VoIP applications in wide area networks.