Performance analysis of synchronous WDM optical packet switches with circular converters

In this paper, I study the performance of a synchronous buffer less WDM Optical Packet Switch (OPS) equipped with circular wavelength converters (CWCs) as compared to the conventional limited-range WCs (LWCs). CWCs allows an input wavelength to be converted to d (conversion distance) adjacent outgoing wavelengths on both of its upper and lower sides. A new scheduling algorithm along with its analytical model for the OPS with CWCs is presented. The model is validated via simulation and is used to study the performance, in terms of packet loss probability (PLP), of CWCs under various percentages of traffic loads. In addition, we study the minimum value of d under which P LP < 10−10 for both CWCs and LWCs. Analysis results show that, for the same PLP and under heavy traffic load, CWCs reduce the value of d by 40 % of that needed by LWCs. As the number of wavelengths increases, the reduction ratio ranges between 20 and 30% of the LWCs case. Under light traffic, packet contention is small; however, a small amount of improvement in the value of d can still be achieved by using CWCs

Keywords:

optical packet switch , synchronous WDM , performance analysis