IP fast reroute with failure inferencing

Abstract

Five nines availability is being expected from IP networks due to the growing popularity of IP telephony and the increasing usage of the Internet for mission-critical applications. This necessitates enhancing the resiliency of IP networks against transient failures that are observed to happen relatively frequently even in well-managed networks. Towards that end, we proposed failure inferencing based fast rerouting (FIFR) approach that exploits the existence of a forwarding table per line-card, for lookup efficiency in current routers, to provide fast rerouting similar to MPLS, while adhering to the destination-based forwarding paradigm. Earlier, we have shown that FIFR can deal with either single link or single node failures in a network consisting of point-to-point links with symmetric link weights. In this paper, we generalize FIFR to handle both link and node failures in networks with asymmetric link weights and multi-access links too. Furthermore, we apply FIFR for protecting against inter-AS failures also. With these extensions, we argue that FIFR elevates the resiliency of any IP network with minimal changes to the forwarding and routing planes.