Comparison of VoIP Performance over WiMAX, WLAN and WiMAX-WLAN Integrated Network Using OPNET

Voice over IP is expected to be in practice in the next generation communication networks. The target of this paper is to analyse its performance in the next generation networks. Among the most competing networks like WiMAX, Wifi, etc., WiMAX having higher bandwidth accommodates more users but with degraded performance. Hence, an integrated network using WiMAX backbone and WLAN hotspots has been developed and VoIP has been setup using SIP. Since, OPNET 14.5.A provides a real life simulation environment, it is chosen as the simulation tool. Quality of the service is critically analysed with parameters like jitter, MOS and delay for various voice codecs. Finally, it is concluded that the WiMAX-WLAN integrated network provides improved and optimal performance over WLAN and WiMAX network with respect to network capacity and quality of service.