基于FDL和TWC的光突发竞争解决方案及性能分析

在光突发交换(OBS)网络中,突发竞争是影响网络性能的一个重要因素,因此如何有效地解决它,成了OBS网络非常重要的问题.在分析当前文献中的解决方案的优缺点后,提出了一种突发竞争解决方案的系统实现.该实现将光纤延迟线(FDL)时城缓存与波长转换器(TWC)波长变换、空城技术结合在一起,构造了一个基于前向转发缓存和反馈循环缓存的两级交换结构.最后从多方面对该系统实现的竞争解决有效性进行了性能分析和计算机仿真,结果表明:它在适当的业务强度(小于0.6)下,能有效改善突发丢失率和突发延迟;同时能降低系统所需的光器件数目.

Optical Burst Contention Resolution Scheme Based on FDL and TWC and Its Performance Analysis

How to resolve the burst contention has become one of core issues of optical burst switching architecture. A systematic implementation for contention is resolution proposed. The implementation mainly builds on broadcast-and-select space switch using tunable wavelength converter(TWC) as feedback wavelength conversion and using fiber delay line(FDL) as forward and feedback buffering. This scheme exploits the simplicity of forward lines and the flexibility of feedback-loop lines in the time domain buffering, and combines the TWC's conversion in the wavelength domain with regeneration for distorted signal. The simulation results show that the scheme can efficiently use FDL buffering and TWC wavelength conversion capacities, and obviously improve the contentions in terms of burst loss probability(BLP) and burst delay under moderate traffic load (<0.6).