Fast control plane for flexible and scalable optical interconnects

The growth of data centers (DC) and high-performance computing (HPC) requires higher bandwidth, but traffic usually occurs between a small number of computing nodes, and the location of the communication bottleneck dynamically changes as the application runs. Therefore, the traditional static network that solves the communication bottleneck by providing excessive bandwidth cannot meet the demand of high performance and low cost at the same time. The reconfiguration of optical interconnects greatly improves the flexibility of the network, which can allocate unutilized bandwidth to node pairs with dense communication and improve resource utilization. However, this flexibility relies on a fast control plane to achieve efficient interaction between devices in the network. We made improvements in traffic collection, topology calculation, and optical switch configuration, and built an experimental platform to evaluate our control plane. The flexibility of optical interconnects shows a good acceleration effect when running applications that solve large-scale problems, and the experimental results show that a proper reconfiguration cycle can reduce the completion time of 3-D Fast Fourier Transform application by up to 53%.