Low-Loss High-Radix Integrated Optical Switch Networks for Software-Defined Servers

Abstract

Software-defined servers provide high flexibility and customizablility with low power consumption. To satisfy the ultrahigh bandwidth requirement of the interconnection of these servers, integrated optical switch networks, based on the recent development of silicon photonics, are promising candidates. In this study, we present a family of floorplan optimized delta optical networks (FODONs) with the proposed stage switches. Both the analytical approximation and the loss model based on the exhaustive search approach are developed to evaluate the loss parameters in the networks. The optimization of the stage switch radix is conducted as well. Results show that when 32 WDM channels are employed, the worst-case loss of the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$ 1024\times 1024$</tex-math></inline-formula> FODON with <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$ 4\times 4$</tex-math></inline-formula> stage switches is only 26 dB, which is 95, 63, 37 dB less than Beneš, Fat-tree, and Baseline networks of the same size, respectively. Furthermore, the average loss and the cost of hardware resources of FODONs are much lower than other networks.