An improvement of weighted round robin cell scheduling in ATM networks

Weighted round robin (WRR) is a common cell scheduling method in ATM switches. In this paper, we study the delay performance of WRR cell scheduling and show that burstiness in input traffic is a major factor in performance degradation. We propose a new WRR scheme: WRR with save and borrow (WRR/SB), that helps improving delay characteristics in real-time traffic, and we provide an analysis of WRR and WRR/SB that describes their delay performance. We show that WRR/SB can provide an improved maximum delay bound over that of WRR alone.