Multicore fiber interconnects for multi-terabit spine-leaf datacenter network topologies

This work demonstrates the use of spatial division multiplexing (SDM) to implement spine-leaf datacenter network topologies. We consider two possible scenarios, with the first consisting of the direct use of high-capacity multicore fiber interconnects. This was implemented with an 8-core multicore fiber to support 64 x 200 Gb/s SDM wavelength division multiplexing (WDM) lanes and combined throughput of 12.8 Tb/s. We also demonstrate a scenario in which each multicore fiber interconnect is used to establish multiple connections between pairs of spin-leaf switches. An optical circuit switch is used between the spine and leaf layers to establish core selective connections, which significantly reduces the number of cables required to implement the network. We demonstrate this approach with a commercial optical circuit switch and 8-core and 4-core multicore fiber interconnects.