冗余PW机制的研究与实现

摘要

Redundant PW is to improve the self-healing of fault. By disposing one or more reserve PW for two communication nodes, the redundant PW group is composed by main and reserve PW. Because of complex network,the redundant PW is variety, which is divided into two modes;stand-alone mode and master-slave mode. Redundancy PW switching consists of an external switching and signaling switching. Redundancy PW switching is achieved via signaling interaction. The establishment and maintenance of PW is realized by extending the LDP (label distribution protocol) ,and based on the message encoding and decoding TLV which is defined by LDP,PW STATUS TLV is added,which can be carried in the MAPPING and Notification message. Simulation results show that the system of redundancy PW can improve the self-healing of communication nodes' fault,so as to improve the whole reliability of the network communication.%冗余PW是为了提高故障的自愈能力,通过为两个通信节点部署一条或多条备用PW,主备PW构成一个冗余PW组.网络的拓扑复杂多变,冗余PW的模型也是多样化的,主要有独立模式和主从模式两种.冗余PW切换主要分为外部切换和信令切换.冗余PW的切换是通过信令的交互实现的.PW的建立和维护是通过扩展LDP( label distribution protocol)协议实现的,其在LDP所定义消息编解码TLV的基础上增加了PW STATUS TLV,该TLV可以在MAPPING消息和Notification消息中携带.研究和实验表明冗余PW机制可以提高通信节点故障的自愈能力,从而提高网络通信的可行性.