A slotted dynamic traffic scheduling algorithm in time-domain wavelength interleaved networks

We consider the scheduling problem in a new optical transport network called time-domain wavelength interleaved networks (TWIN). Due to the innovative architecture of TWIN, four issues are essential in the designing of scheduling schemes: there are no transmitting/receiving conflicts; propagation delays are observed; throughput is maximized; queueing delay and delay variance are kept as small as possible. We formulate the scheduling problem into an integer linear programming (ILP) problem and present a novel heuristic algorithm - the destination slot set (DSS) algorithm. We compare the performance of DSS with an existing algorithm in TWIN - dynamic scheduling (DS), and show that while achieving the maximum throughput, DSS introduces much smaller queueing delay and delay variance than DS. We highlight that this is a requisite for providing QoS in TWIN, which was overlooked by previous works. We also show that DSS has a smaller computing complexity than DS, which makes it feasible for real-time scheduling.