一种新的WDM光网中的共享链路保护策略

研究了WDM光网中的链路保护问题.提出了一种新的共享链路保护策略--基于SRLG的共享链路保护策略(SRLG-SLP).SRLG(共享风险链路组)定义了对一条工作光通道分配保护资源时的资源可用性的约束.它规定任意两条有着同样故障风险或者说处于同一个SRLG的工作光通道不能利用同样的保护资源.另外,还提出了一种更加符合实际的单链路故障模型,其中链路故障间隔时间和链路故障保持时间被考虑作为两个独立的变量.基于该链路故障模型,通过大量的仿真试验,比较了专用链路保护(DLP)、共享链路保护(SLP)和提出的SRLG-SLP保护策略的资源利用率、保护效率以及业务中断率.结果显示,我们提出的SRLG-SLP在保护效率和业务中断率方面的保护性能远好于DLP和SLP,但会牺牲一些资源利用率.

A New Shared Link Protection Scheme in WDM Optical Networks

The problem of link protection schemes in WDM networks with dynamic traffic demands is addressed. A new link protection method is proposed, i.e. SRLG-based shared link protection (SRLG-SLP). The SRLG (Shared Risk Link Group) constraint defines the availability of protection resources to a working path, which requires that any two working paths sharing the same risk of failure (or in the same SRLG) cannot share the same protection resources. Furthermore, in this study, a more practical single-link failure model is considered, in which the link-failure-interarrival time and link-failure-holding time are considered as two independent factors. Based on this link-failure model, extensive numerical simulations are done to compare the resource utilization, protection efficiency and service disruption ratio between SRLG-SLP, shared link protection (SLP) and dedicated link protection (DLP) schemes. Simulation results show that the developed SRLG-SLP protection scheme performs very well in terms of protection efficiency and service disruption ratio, while will sacrifice some performance in terms of resource utilization.