Utilization of PIM-DM in IP fast reroute

After a network node or a link fails, an unpredictable period of time ensues during which the network communication is disturbed. This period encompasses the time necessary for the network to reconverge on new shortest paths. This process may last from a few miliseconds up to tens of seconds. The time heavily depends on the physical topology and the routing protocol used. During the failure and reconvergence period, the network is experiencing serious connectivity issues in which different destinations may become unreachable causing other difficulties, e.g. with critical and sensitive services. Addressing these issues, IP Fast ReRoute (IP FRR) mechanisms have been developed. The main goal of IPFRR mechanisms is to minimize network recovery time by computing repair paths for possible node or link failures before they happen. Several IPFR mechanisms exist, ranging from selecting loop-free alternatives to other ones using tunneling mechanisms. In this paper we are proposing a new multicast based mechanism for IPFRR recovery in an IPv6 network. Our proposed mechanism uses a modified algorithm of the Reverse Path Forwarding (RPF) control used by Protocol Independent Multicast - Dense Mode (PIM-DM) multicast routing.