An Integrated Uplink Scheduler in IEEE 802.16

The absence of algorithms for quality of service (QoS) scheduling algorithms in the 802.16 standard allows vendors to develop their own algorithms for bandwidth allocation and service differentiation of their product. Deficit round robin (DRR) scheduling algorithm which provides fair queuing at O(1) complexity. However, due to its round robin structure, it is not adequate for handling latency critical applications, such as voice. For this reason, this paper proposes a modified version of the DRR algorithm to solve this problem, while preserving the simplicity available in the original DRR design. This algorithm is designed to serve different types of service flows in the uplink, which guarantees lower latencies. In this paper the performance of this schema with deficit round robin is compared using the OPNET WIMAX model. The comparison is carried out via simulation, by investigating the latency and bandwidth sharing properties of the algorithms.