Novel scheduling algorithm based on packet aggregation effect for optical switches

The packet scheduling in optical switches has to be frame based because the configuration consumes much time. The frame size is usually selected to be large enough in order to improve transmission efficiency, leading packet aggregation effect. With consideration of the packet aggregation effect, a novel packet scheduling algorithm called permutation-based longest queue first + hold (p-LQF + Hold) was proposed. A set of permutations were calculated by using of the traffic requirement matrix. The permutation with the largest matched occupancy was used to find the matching on each frame boundary. Simulation was made on a 4 × 4 virtual output queue (VOQ) optical switch under uniform, nonuniform and diagonal Bernoulli and ON/OFF traffic patterns, respectively. The simulation results show p-LQF + Hold can achieve 100% throughput under any admissible traffic that satisfies the strong law of large numbers, and has close to or even lower average packet delay than the popular LQF + Hold algorithm, p-LQF + Hold can guarantees bandwidth requirement and short-term fairness and efficiently accommodate the dynamical packet arrivals.