核心链路感知的可生存虚拟网络链路保护方法

针对现有可生存虚拟网络链路保护方法无差别对待所有虚拟链路、备份资源消耗多且故障后网络恢复时延长的问题，该文提出一种核心链路感知的可生存虚拟网络链路保护(CLA-SVNLP)方法。首先，综合考虑虚拟链路动态和静态两方面因素构建虚拟链路核心度度量模型，依据虚拟网络生存性需求，对核心度较高的虚拟链路进行备份保护；其次，将p圈引入可生存虚拟网络链路保护，依据虚拟网络特点构建p圈，为核心虚拟链路提供1:N保护，即每条核心虚拟链路平均消耗1/N条的备份链路带宽资源以减少备份链路资源消耗，并将单物理链路保护问题转化为多个p圈内的单虚拟链路保护问题；最后网络编码技术与p圈结合，将备份链路对核心虚拟链路提供的1:N保护转化为1+N保护，避免了故障后定位、检测及数据重传。仿真结果表明，该方法提高了备份资源利用率且缩短了故障后的网络恢复时延。

Core Link Aware Survivable Virtual Network Link Protection Method

In order to solve the problems of all virtual links take without discrimination, high backup resource consumption and long network recovery delay after failures in existing survivable virtual network link protection methods, a Core Link Aware Survivable Virtual Network Link Protection (CLA-SVNLP) method is proposed. At first, the core degree metric model of virtual link is constructed by considering virtual link dynamic and static factors. According to virtual network survivable needs, virtual links with high core degrees are protected by backup resources. Then the p-cycle is introduced into survivable virtual network link protection and the p-cycle is constructed based on the characteristics of virtual network to provide 1:N protection for core virtual links. That means each core virtual link consumes 1/N backup link bandwidth resources and the backup link resource consumption is reduced. It also transforms the single physical link protection into single virtual link protection in multiple p-cycles. At last, the network coding and p-cycle are both used to transform the 1:N protection into 1+N protection for core virtual links which avoids fault location, detection and data retransmission after failures. Simulation results show that the proposed method can improve the utilization of backup resource and shorten the network recovery delay after failures.