On the performance of a large-scale optical packet switch under realistic data center traffic

High-speed, submicrosecond-latency, large-port-count (thousands) optical packet switches (OPSs) for intercluster communication networks can become a key element in the deployment of cloud-oriented large-scale data centers. In this work we numerically investigate the performance of a large-port-count wavelength-division multiplexing (WDM) OPS based on a Spanke-type architecture with highly distributed control. We analyze it under a data center traffic modelto determine its suitability for this type of environment. Results indicate that the proposed architecture can be scaled to 4096 ports while providing packet loss below 10^-6 and latency under 1 μs, with a total switching capacity over 55 Tbits/s. Additionally, we propose and analyze two WDM OPS architectures. The first one detects and processes small and large-sized Ethernet packets with two parallel switches. The second architecture includes multiple receivers to decrease packet losses and latency while using very limited electronic buffers. Results indicate that both techniques can lead to substantial improvements. In terms of packet loss and latency, they allow up to 40% higher input load with respect to the original WDM OPS architecture.