抗毁WDM网中单SRLG故障的共享子通路保护

该文针对抗毁WDM网中单个共享风险链路组(Shared Risk Link Group,SRLG)故障,提出了一种动态共享子通路保护(Dynamic Shared Sub-Path Protection,DSSPP)算法.DSSPP为每条业务请求选择一条工作通路后,按照参数m把工作通路划分成若干条等长的子通路,其中m为子通路的长度,并为每条子通路各选择一条SRLG分离的保护通路.如果两条子通路SRLG分离,则它们对应的保护通路可以共享相同资源.在进行路由选择时,DSSPP考虑了负载均衡度和资源共享度,因此能有效地提高资源利用率和降低业务阻塞率.仿真表明,DSSPP不仅能保护单SRLG故障,而且能灵活地在资源利用率(阻塞率)和保护切换时间之间进行性能折衷.

A Shared Sub-path Protection for a Single SRLG Failure in Survivable WDM Networks

This paper proposes an algorithm, called Dynamic Shared Sub-Path Protection (DSSPP), for protecting a single Shared Risk Link Group (SRLG) failure in survivable WDM mesh networks. DSSPP firstly searches a primary path for a connection request, and it follows to segment the primary path into several equal length sub-paths according to the m, where the m is the length of the sub-path, and searches a SRLG-disjoint backup path for each sub-path. If two sub-paths are SRLG-disjoint, then their corresponding backup paths can share the common resources. When computing paths, DSSPP considers the load balance and the resources sharing degree, so that the paths are the minimum cost, and the resource utilization ratio can be improved and the blocking ratio can be reduced. The simulation results show that DSSPP not only can completely protect a single-SRLG failure but also can make the trade-offs between the resource utilization ratio (or blocking ratio) and the protection-switching time.