Performance Evaluation of Quality of Service Classes in WiMAX Networks

Abstract

Nowadays, the desire of internet access has influenced quite a large number of users to access high quality video application. In wireless medium, video applications still have high resource requirements, for example, bandwidth and traffic priority. For this challenges, The IEEE 802.16e defined five different Quality of Service (QoS) classes including UGS, ertPS ,rtPS, nrtPS and BE. It is well known that UGS is designated to support QoS for voice without silence suppression and video conference applications and ertps is designed also to support real time application but with silence suppression, as for rtps is designed to support video and audio streaming. The other two classes have different applications .In this research we investigate the performance of UGS, ertps and rtPS QoS classes in terms of multimedia applications such as videoconferencing and voip over WiMAX network scenarios .There were six scenarios have been implemented at the same topology but different traffic type, three of them used video conferencing application and others used voip application, also a certain combination of users that are allocated a QoS and a selected application. These selected application had priority of allocating resource by QOS classes for each scenario .The OPNET modeler 14.5 simulator is employed for simulation purposes in order to evaluate the performance of UGS, ertps, and rtPS of video conferencing and voip applications. The results show that the user with UGS QoS class could provide higher throughput which 37% and 33% more than rtPS class , lower end to end delay which is 66% and 52% more than rtPS class ,finally lower packet delay variation which are 80% and 68% more than rtps class for video and VoIP respectively. So UGS offered the highest performance.