Performance of dilated banyan network with back-pressure mechanism

Abstract

A dilated banyan network is one solution that can overcome the internal blocking problem in a banyan network. However, tremendous routing capacity is wasted in the dilated banyan network because d − 1 links of each input port in the first stage are unused. In this paper, we propose a dilated banyan network with back-pressure mechanism to fully utilize the wasted routing capacity. The proposed switch has input and output queues, and employs a priority scheme to prevent out-of-sequence. We also design a non-blocking element in order to reduce the hardware complexity of the dilated banyan network. The performance of the proposed switch is analyzed under uniform traffic assumption. Numerical and simulation results show that the proposed switch yields a significant improvement of the maximum throughput as compared to that of the pure dilated banyan network. Moreover, with dilation degree of d = 3, the maximum throughput of about 1 is achieved.