Revisiting WFQ: Minimum Packet Lengths Tighten Delay and Fairness Bounds

In this paper we consider the bounds on the sample path discrepancy between the ´idealized´ generalized processor sharing (GPS) and the ´practical´ weighted fair queueing (WFQ) scheduling disciplines. We show that when both the minimum packet lengths and the weights are non zero, the discrepancy bounds can possibly be tighter than that in (A. Greenberg, et al., 1992) and (A. Parekh, et al., 1993) This new upper bound on the delay discrepancy is then used to provide an upper bound on the discrepancy in the instantaneous throughput, which can also be significantly tighter than those in (A. Greenberg, et al., 1992) and (A. Parekh, et al., 1993)