Weighted max-min fair scheduling in input-queued crossbar switches

Abstract

The input-queued switching architecture, because of its scalability, has become attractive for implementing high-speed switches and routers. For an input-queued switch, it is challenging to provide a scheduling scheme that is both highly efficient and fair in bandwidth allocation. Existing schedulers attempt to improve throughput by scheduling cells free of contention for transmission, at the expense of delay and fairness. In this paper, we proposed a weighted max-min fair scheduling (WMFS) scheme for input-queued switches that provides weighted max-min fair bandwidth allocation distribution among the flows. Results from simulation show that the scheme is able to achieve asymptotically 100% throughput and low cell latency under uniform traffic, and, provide approximately weighted max-min fair bandwidth allocation and normalized fair service guarantees in the presence of misbehaving traffic.