An upper bound on blocking probability of vertical stacked optical benes networks

Abstract

Directional coupler (DC)-based optical switching networks can switch signals at the rate of several terabits per second. Benes networks are widely employed for their small depth and self-routing capability. Crosstalk between two optical signals passing through the same DC is an intrinsic drawback in DC-based optical networks. Vertical stacking of multiple copies of an optical Benes network has been intensively studied by researchers to build non-blocking optical networks. The resulting network is called vertically stacked optical Benes network (VSOBN). However, no rigorous analysis has been done to predict the behavior of VSOBN. In this paper, we study the deterministic conditions for strictly non-blocking VSOBN with and without worst case scenarios. We further analyze the blocking probabilities of VSOBN networks under a fixed load and develop their upper bound with respect to the number of planes in the networks. These performance measures can be used to predict the performance of VSOBN. © Springer-Verlag Berlin Heidelberg 2005.