Fast scheduling for optical packet switches with minimum configurations

Scheduling optical packet switches with minimum configurations has been proven to be NP-complete. Moreover, an optimal scheduling algorithm produce as many as /spl theta/(log N) empty slots in each switching per time slot for an N /spl times/ N optical switch. The best known algorithm approximates the optimal solution in O (N/sup 3.5/) time. In this paper, we propose an algorithm called DNC with minimal time complexity /spl theta/(N/sup 2/) based on divide-and-conquer paradigm. The number of empty slots created by our algorithm is upper bounded by /spl theta/(N). However, simulation results indicate that it is approximately O(log N) on average. Therefore, our algorithm is more practical and beats the previous ones when optical switches have large reconfiguration overhead.