一种按需域间路径构建方法

摘要

在域间路由中,BGP的最优路径转发规则使得节点无法控制自身能够收到哪些路径.针对该问题,提出了一种按需的域间路径构建方法,其主要特点为上游节点可以对其下游节点的选路过程施加影响,根据自身需求定制路径.首先对BGP进行扩展,提出了一种支持在路径通告中嵌入更多策略信息的域间路由协议P-BGP,嵌入在路径通告中的策略能够指导中间节点如何选路.在P-BGP的基础上,进一步提出了支持按需的域间路径构建方法OIPBM,OIPBM以BGP保证源端与目的端的可达性,需要构建特殊路径的源端将路径构建的需求信息发送至目的端,由目的端协助其发起一个带策略的P-BGP收敛过程获取满足需求的路径.在理论分析的基础上,通过实验验证了OIPBM具有较好的性能.%In inter-domain routing,the optimal path forwarding rule of BGP makes nodes not control what paths they can receive.An on-demand inter-domain path building method (OIPBM) is proposed,whose main feature is that nodes can lay control over the path selecting process of their downstream nodes and customize the routes according to their own requirements.Firstly,by extending BGP,a new protocol called P-BGP is proposed,which adds more policy options into routing advertisements.The inserted policies can be referred by the intermediate nodes when selecting paths.Secondly,based on PBGP,OIPBM is proposed.OIPBM uses BGP to ensure that the source and the destination nodes are reachable,and any source node that requires a special path to destination node can request the destination to start a politic P-BGP convergence process to find the satisfying path.Based on theoretical analysis,OIPBM is demonstrated to have good performance by experiments.