Redundant trees for fast IP recovery

Slow convergence of IP routing in case of network component failures represents a problem for emerging time-critical network applications. It has motivated work on IP fast reroute mechanisms that use local, proactive recovery in order to immediately provide alternative routes for the affected data packets. We present a new mechanism for IP fast recovery called IP Redundant Trees (IPRT). IPRT builds two redundant trees per network destination and pre-calculates backup next hops based on them. Combined with a smart forwarding scheme, IPRT provides proactive, local and loop-free recovery in connectionless IP networks. IPRT is simple and flexible, and requires a low increase of the routing state amount. We evaluate several key performance metrics in IPRT and other actual IP fast recovery proposals and argue that IPRT indeed has very attractive properties.