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
${64} \times {200}\;{\rm Gb/s}$
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.