Performance Evaluation of VOIP Codecs Over Wi-Fi WIMAX

Voice over IP (VoIP) applications such as Skype, Google Talk, and FaceTime are promising technologies for providing low cost voice calls to customers over the existing data networks. Wireless networks such as Wi-Fi and WiMAX focus on delivering Quality of Service (QoS) for VoIP applications. However, there are numerous aspects that affect quality of voice connections over wireless networks. In this paper, we evaluate performance of three VoIP codecs over Wi-Fi and WiMAX networks. OPNET Wi-Fi and WiMAX simulation models are designed to generate and evaluate performance metrics such as Mean Opinion Score (MOS), average end-to-end delay, and jitter.