A Dynamic Weighted Round-Robin Scheduling in ATM Multiplexer

Abstract

The weighted round-robin (WRR) scheduling in ATM multiplexer has been proven to be an effective and simple method to implement for priority traffics. However, it is hard to determine exactly how much weight should be assigned to a variable bit rate (VBR) source. Beside, its delay performance becomes poor under bursty traffic conditions, especially for VBR video sources. In order to improve performance of multiplexer, changing weight dynamically and, if handling video sources, smoothing video traffic are the ways. For multiplexing schedulers, we propose a new dynamic weight-based Round-Robin scheduling scheme. It shows that the new proposed scheme provides delay performance about 81% improvements over the WRR. In smoothing video traffic, we find that the demand of bandwidth and the cell loss probability can be greatly reduced, if we control the initial time of each video connection. Through these two ways, we can improve the system performance which includes reducing the bandwidth requested, the waiting time, and cell loss probability.