A Packet Scheduling To Enhance Quality of Service in IEEE 802.16

Wireless Broadband Network like the standardized IEEE 802.16, popularly referred to as WiMAX is known for its differentiation of Quality-of-Service (QoS) feature based on the traffic requirement. However the QoS differentiation process is often unfair especially to traffic classes which do not require high QoS. Such traffic classes are often starved to the extent that they experience extremely low throughput. In this paper, we look into a scheduling algorithm for providing QoS in Wireless Broadband Networks which alleviates this unfairness. The algorithm implements two queuing theory principles - Earliest Deadline First (EDF) and Weighted Fair Queuing (WFQ) to assure QoS to various classes of traffic. We propose an enhancement to the EDF queuing principle to ensure that lower priority traffic do not starve. We simulated the algorithm in dot net framework using the programming language C#. Our simulation results show considerable improvement in the throughput of low priority traffic while retaining the packet delay constraint of the high priority traffic classes.