Performance analysis and comparative study of voice over IP using hybrid codec

This paper investigates and compares the performance of the popular VoIP codecs G.711, G.723.1 and G.729A over an IP network based on SIP architecture, using RTP as a transport protocol. This is based on different simulations in order to evaluate the performance of each codec and to find the optimal codec. For this objective this paper analyzes Quality of service (QoS) parameters, principally delay, jitter, Mean Opinion Score (MOS) and throughput. The OPNET Modeler 14.5 has been used for implementing this work and monitoring all results in order to choose the best codec for transporting the voice over an IP backbone.