A load-balanced crosspoint-queued switch fabric

Abstract

The fast growth of Internet has created the need for high-speed switches. Recently, the crosspoint-queue switch has attracted attention because of its scalability and high performance. However, the Cross-point-Queue switch does not perform well under non-uniform traffic. To overcome this limitation, the Load-Balanced Cross-point-Queued switch architecture has been proposed. In this architecture, a load-balance stage is placed ahead of the Cross-point-Queued stage. The load-balance stage transforms the incoming non-uniform traffic into nearly uniform traffic at the input port of the second stage. To avoid out-of-order cells, this stage employs flow-based queues in each crosspoint buffer. Analysis and simulation results reveal that under non-uniform traffic, this new switch architecture achieves a delay performance similar to that of the Output-Queued switch without the need for internal acceleration. In addition, its throughput is much better than that of the pure cross-point-queued switch. Finally, it can achieve the same packet loss rate as the cross-point-queue switch, while using a buffer size that is only 65% of that used by the cross-point-queue switch.