基于关键网络状态的域内路由可用性研究

业界通常采用路由保护方案来提高域内路由可用性.然而已有的路由保护方案存在下面两个方面的问题:a)没有考虑网络中链路的失效概率,同等对待网络中所有的链路,事实上在互联网中,不同链路的失效概率是不同的,因此应该在路由保护方案中考虑链路的失效概率;b)将保护链路的数量作为设计目标,事实上方面某些链路出错的概率非常低,保护这些链路反而会增加开销,而另一方面某些链路出错的概率非常高,需要重点保护这些链路.因此应该将路由可用性作为路由保护方案的设计目标.针对上述两个问题,提出了一种基于关键网络状态的域内路由保护方案(RPBCNS),该算法首先通过链路失效概率计算出所有的关键网络状态,然后在每种关键网络状态下计算节点对之间相应的路径,保证节点对之间路径的多样性,从而使得尽可能多的节点对满足路由可用性需求.仿真实验将RPBCNS算法与主流算法ECMP、DC、path splicing分别在三个真实网络中进行对比,在网络可用性和节点对可用性满足率上RPBCNS的性能明显优于其他三种算法.仿真结果表明,RP-BCNS不仅具有较高的网络可用性,并且能够使得尽可能多的节点对满足路由可用性目标,更符合实时应用的实际需求.

Research on intra-domain routing availability based on critical network state

The industry usually adopts route protection scheme to improve the availability of intra-domain routing. However, the existing routing protection schemes have the following two problems: a) the failure probability of links in the network is not considered, and all links in the network are treated equally. In fact, in the Internet, the failure probability of different links is different, so the failure probability of links should be considered in the routing protection scheme. b) In fact, the protection of some links with high probability of error will increase the protection cost of some links. Therefore, routing availability should be the design goal of route protection scheme. To solve these two problems, this paper proposed an intra-domain routing protection scheme based on critical network state(RPBCNS). The algorithm first calculated all the critical network states through the link failure probability, and then calculated the corresponding paths between node pairs in each critical network state to ensure the diversity of paths between nodes, so as to make as many nodes as possible meet the routing availability requirements. The simulation experiment compared the RPBCNS algorithm with the mainstream algorithms ECMP, DC, and path splicing in three real networks. The performance of RPBCNS is better than the other three algorithms in terms of network availability and node availability satisfaction rate. Simulation results show that RPBCNS can make as many node pairs as possible to meet the routing availability goal, which is more in line with the actual needs of real-time applications.