FlexNet: A Optical Switching Architecture for Optical Data Center Networks

Past few years have witnessed the rapid development of Optical Circuit Switches (OCSes), which support high and dynamic bandwidth with low cost in the data center network. As a result, some optical network architectures based on OCSes, such as OSA, Mordia and Rotornet, have been proposed one after another. Rotornet, as a typical optical network architecture, requires all switches to rotate independently through a fixed set of configurations to provide uniform bandwidth between across all endpoints. The configuration algorithm in RotorNet is extremely insensitive to traffic, resulting in poor performance under non-uniform traffic. A mismatch between the network topology and traffic pattern can result in wasted bandwidth on links with minimal or no traffic. In this paper, an optical switching architecture, FlexNet, is proposed to improve the utilization of optical link resources. In FlexNet, a centralized controller is added to estimate traffic demands, and a more flexible configuration algorithm is designed to change the network topology efficiently, which can also be well applied to Rotornet. We evaluated the latency and throughput performance of FlexNet, Rotornet, and Mordia using the OMNET ++ simulator. The experimental results show that FlexNet has better performance than Rotornet and Mordia in different traffic patterns.