Experimental evaluation of multimedia services in WiMAX

WiMAX is a new technology that can provide long distance broadband wireless access based on IEEE 802.16 standards. After a short overview of IEEE 802.16 and the WiMAX network architecture, we center on the Quality of Service (QoS) support for multimedia applications in WiMAX. Inherent QoS support is an important factor differentiating WiMAX from other wireless access technologies, but so far has not been studied using off-the-shelf equipment. We fill this gap by empirically quantifying the performance of different multimedia applications and scheduling services in a WiMAX testbed. Specifically, the performance attained by multimedia applications over fixed WiMAX links, configured with Best Effort and Real Time Polling scheduling service classes is presented. We measure performance under both over-provisioned and under-provisioned configurations. When resources are substantially over-provisioned, the WiMAX equipment performs well and application requirements are fulfilled as expected. On the other hand, in under-provisioned conditions, applications using the Real Time Polling scheduling service enjoy better performance than those using the Best Effort scheduling service, but we note that proper configuration of the service flows may not be straightforward in practice.