Urgency-based round robin: a new scheduling discipline for packet switching networks

Packet scheduling is one of the key mechanisms that will be employed in the network nodes (routers and switches) for supporting multiple quality of services. We propose a new packet scheduling algorithm called urgency-based round robin which computes an index for flows in order to keep track of instantaneous bursts. With this approach, flows which might be in need of momentary service can be detected. Also, we propose a novel weight allocation scheme to be used together with the scheduler with the aim of preventing network under-utilization. Our algorithm can be considered as a version of the weighted round robin (WRR) with improved delay characteristics. After an introduction about the necessity of a scheduler, we describe related work and necessary background for the rest of the paper. Next we describe the operation of our algorithm. We then give some simulation results showing the delay performance of the proposed algorithm comparing it to that of the WRR. Also, we remark on the issue of necessary bandwidth reservation. We conclude by describing future extensions to the algorithm