Silicon Photonic Flex-LIONS for Bandwidth-Reconfigurable Optical Interconnects

This paper reports the first experimental demonstration of silicon photonic (SiPh) Flex-LIONS, a bandwidth-reconfigurable SiPh switching fabric based on wavelength routing in arrayed waveguide grating routers (AWGRs) and space switching. Compared with the state-of-the-art bandwidth-reconfigurable switching fabrics, Flex-LIONS architecture exhibits 21 less number of switching elements and 2.9 lower on-chip loss for 64 ports, which indicates significant improvements in scalability and energy efficiency. System experimental results carried out with an 8-port SiPh Flex-LIONS prototype demonstrate error-free one-to-eight multicast interconnection at 25 Gbs and bandwidth reconfiguration from 25 Gbs to 100 Gbs between selected input and output ports. Besides, benchmarking simulation results show that Flex-LIONS can provide a 1.33 reduction in packet latency and > 1.5 improvements in energy efficiency when replacing the core layer switches of Fat-Tree topologies with Flex-LIONS. Finally, we discuss the possibility of scaling Flex-LIONS up to N 1024 ports (N M W) by arranging M-2 W-port Flex-LIONS in a Thin-CLOS architecture using W wavelengths.