An Evaluation of Deficit Round Robin Fair Queuing Applied in Router Congestion Control

In this paper, we evaluate the performance of Deficit Round Robin Fair Queuing applied in router congestion control. Two parameters affect the performance of a DRR router: the number of flows and the buffer size. We study the influence of the two parameters on fairness. The results show that the optimal region can be achieved by means of one-dimensional optimization. Then, we investigate the impact of the packet size, bandwidth, and queuing management on a flow in a simple network by means of 2 factorial design. Three factors are considered to analyze the performance of the delay and the packet arrival ratio for a flow: the packet size, bandwidth, and queue type. In the performance study on the packet arrival ratio, we find that the effects of the bandwidth and packet size are predominant. However, in the performance study on the delay, we find that the effect of the queue type is as great as that of the bandwidth. Active queuing management, such as DRR, which allocates bandwidth fairly, can also improve the delay performance of a flow.