Retransmission Schemes for Lossless Transparent Optical Packet Switching in Large-Scale Datacentre Networks

We propose a transparent optical packet-switched network as a solution to providing a high-capacity datacentre core network, interconnecting electronically-switched cluster switches. We show that optical packet switches, with limited optical buffer capabilities, can support heavy inter-cluster traffic without packet loss when used with an optical packet retransmission scheme, that uses the already-available electronic buffering capacity in cluster switches. Through simulations, we show good latency performance under both uniform and hot-spot traffic patterns. The impact of extending link lengths on retransmission performance is also investigated.