Weighted scheduling based on queue length and delay for AOPS

Abstract

Packet scheduling plays an important role in the asynchronous optical switched networks for node performance. A weighted scheduling algorithm based on the queue length associated with waiting delay was proposed to solve the packet starvation of queue length weighted scheduling for the length variable OPS. The contention is resolved either in wavelength domain by limited range wavelength converters and in time domain by fiber delay lines. The work has contributed with a very powerful scheduling mechanism which reduces resource contention at the asynchronous OPS core nodes and guarantees a reasonable packet delay thanks to its weighted scheduling algorithm based on queue length and waiting delay for variable length OPS network. The scheduler calculates every input ports with N×K virtual output queue (VOQ) weight and schedules the maximal weight queue packets to available output channel. The analysis and simulation results show that the proposed scheduling has high throughput and low packet loss ratio.