Frame-based Matching Algorithms for Optical Switches

Virtual Output Queuing is widely used by fixedlength high-speed electronic switches to overcome head-of-line blocking. This is done by means of matching algorithms. These matching algorithms have typically been cell-based. That is, in every time slot, a new matching set is calculated and the switch fabric is updated to connect matched inputs and outputs. Fabric reconfiguration in an optical switch is not as fast as in an electronic switch. During reconfiguration, no data can be transferred. Given this overhead, it is not efficient to update connections between inputs and outputs for every time slot. In this paper frame-based matching algorithms for optical packet switches are presented, so that connections can be updated less frequently to reduce the bandwidth loss. The implementation complexity and performance of these schemes are studied. Zndex Termsoptical switching, scheduling, Virtual Output Queueing, exhaustive service, polling systems.