Multi-cabinet implementation for Load-Balanced Optical Switch

Load-Balanced Optical Switch (LBOS) 20] ensures close-to-100% throughout and all-optical transmission between linecards. In this paper, we extend LBOS for multi-cabinet implementation. The challenges lie in the fact that the practical implementation requirements in single-cabinet LBOS become un-scalable for multi-cabinet scenario. First of all, we remove the restriction on LBOS that propagation delay (t_p) between adjacent linecards must equal to the transmission time (t_pkt) for sending one packet. The delay t_p is relaxed to be any value, which can accommodate the long and unequal distances fibers among cabinets. Secondly, we outstrip the upper bound of switch size N = 160 in LBOS. The basic idea is that the adjacent linecards share an identical channel/wavelength. Then LBOS can be scaled to support the large switch size of multi-cabinet. Last but not least, a more feasible fair scheduler is devised to replace the original one in LBOS. The simulation results show that multi-cabinet LBOS yields a much better delay/throughput performance than other multi-cabinet optical switches (e.g. Fasnet 8]).