基于SRLG不相关的共享保护算法的研究

通过对共享保护算法的深入分析,使用K条最短路和迭代思想的方法,提出了两种共享风险链路组不相关的共享保护算法,并在仿真平台上对两种算法的性能进行了仿真.KWFF算法借鉴了传统的K条最短路策略,并且在每一个波长平面上,都对新到业务进行了K条工作路由的计算,极大挖掘了网络中潜在的波长资源.而IFF算法由于引入了迭代的思想,避免了共享风险链路组问题中,所特别有“陷阱”问题的出现,并且利用两套权重计算公式,在计算工作路由和保护路由的时候,充分考虑了网络资源的实时变化情况.通过仿真数据可以看到,与以往算法相比,KWFF和IFF算法大大降低了网络阻塞率,并且提高了网络资源的使用效率.

The Study of Shared Protection Algorithms Under Share Risk Link Group Constraints

Network survivability has been one of the key topics when researching the optical network.For network survivability,select two routes should be selected that are disjoint when computing the working route and protecting route or restoring route.The purpose of the shared-protection algorithms under Shared Risk Link Group (SRLG) constraint is to search two routes that are disjoint from SRLG.Two shared-protection algorithms under Shared Risk Link Group (SRLG) constraint will be presented;they are KWFF and IFF algorithms.In the KWFF algorithm,the K-Shortest-Path (KSP) strategy is introduced on every wavelength plane to search usable resources adequately in the network,the working route and protecting route on every wavelength plane can be selected from the backup route set.And with the iterative strategy and the double weights of link,IFF algorithm could avoid the trap that can result in deteriorating the network performance.The simulation and results analysis will be in terms of two parts,the one is from the network performance, and other one is from the resources utilization.From the simulation results,it will be found that compared with other algorithms,KWFF and IFF algorithms could decrease the block probability and improve the performance in the network.