IP Local Node Protection

Network survivability has become one of the most important QoS (quality of service) parameters in IP network services. IP protection can improve network resilience and avoid service disruption better than traditional routing recovery or other lower layer recovery technologies. In this paper, we proposed an IP local node-protection (IPLNP) scheme based on the characteristic of shortest path routing in IP networks. Our schemes working in an intra-area routing domain provide simple and efficient solutions to improve IP network survivability. Unlike source-routing-based MPLS (multiprotocol label switching) fast-reroute which needs an extra MPLS layer and complex control protocols, our scheme are applicable to a network employing only conventional IP routing and forwarding. Our scheme can prevent service disruption and packet loss caused by the loops which normally occur during the re-convergence of the network upon a failure. Because the backup next hops are predetermined in advance, the service interrupted time can be limited to a few milliseconds. In the simulation results, we observe that IP local node-protection scheme can efficiently improve network survivability while single node failure occurs.