弹性光网络中面向可靠性的链路故障概率保护与保护资源重配置策略

Reliability-oriented Links Failure Probability Protection and Backup Reprovisioning Strategy for Elastic Optical Networks

为解决弹性光网络中多链路故障保护的高保护资源冗余度问题,该文提出一种面向可靠性的多链路故障概率保护与保护资源重配置(ROPP-BR)策略。在ROPP-BR策略中,该文综合考虑频谱资源消耗和链路故障概率,分别设计了工作与保护路径的链路代价函数,以较小代价分别选择业务可靠性高且频谱资源消耗少的备选工作与保护光路。为满足业务差异化的可靠性需求,ROPP-BR策略设计了一种面向可靠性的概率保护机制,建立了业务可靠性评估模型,在满足业务的可靠性需求的限制下灵活地配置概率保护路径。当业务将要被阻塞时,该文提出一种基于极大团的保护光路重配置方法,对网络中的业务保护资源进行重配置,提高保护频隙的共享度。仿真表明,所提策略兼顾了带宽阻塞率与可靠性性能,有效地降低了保护资源冗余度。

Due to the high resource redundancy of full protection for request＇s multi-link failure in elastic optical networks, a strategy of Reliability Oriented Probability Protection and Backup Reprovisioning（ROPP-BR） is proposed. In the ROPP-BR, an adaptive adjustment working and protection link cost functions are devised to effectively select the alternative working and protection light-paths respectively which have high reliability and consume a small amount of spectrum resources in the multi-link failure. The cost function sufficiently considers the spectrum resources consumption and the link failure probability for both working and protection paths. Meanwhile, in order to satisfy the differentiated reliability requirements, a reliability oriented probability protection mechanism is introduced. And a theoretical analysis model is established to estimate the service reliability for lightpaths in optical networks with probability protection, so the probability protection path can be flexibly configured under the restriction of the reliability requirements of the request. Moreover, for further improving protection sharing efficiency, when the request will be blocked for shortage of idle spectrum resource, a backup reprovisioning method based on maximum clique, is put forward to reconfigure the protection paths and spectrum resources. The simulation results indicate that the proposed ROPP-BR strategy can synthetically consider the performance of bandwidth blocking probability and service reliability, and effectively reduce the redundancy of protection resources.