Scheduling techniques in an integrated hybrid node with electronic buffers

Integrated hybrid optical packet/circuit switched architectures enable networks with the guaranteed service transport (GST) of circuit switching and the statistical multiplexing known from packet switching. The utilization of the optical lightpaths is increased by inserting low priority statistically multiplexed (SM) traffic in the guaranteed circuit switched traffic gaps. Previous studies of these nodes have used optical packet switches together with reservation techniques to minimize the SM packet losses while giving absolute priority to circuit switched traffic. In this paper we propose a novel scheduling technique that applies electronic buffers and multiple queues to find a suitable SM packet to fit in a GST gap. Additionally, two schemes of managing the output buffer are introduced, the dedicated queue per input and the length-aware buffering. Simulation results demonstrate that their combination significantly increases the utilization of the available capacity and the maximum rate of SM traffic inserted in the network.