IP Fast Re-Route with Fast Notification
Ericsson
Ericsson
Ericsson
Telcordia
Telcordia
This document describes the benefits and main applications of sending explicit fast notification (FN) packets to routers in an area. FN packets are generated and processed in the dataplane, and a single FN service can substitute existing OAM methods for remote failure detection, such as a full mesh of multi-hop BFD session. The FN service, therefore, decreases network overhead considerable. The main application is fast reroute in pure IP and in IP/LDP-MPLS networks called IPFRR-FN. The detour paths used when IPFRR-FN is active are in most cases identical to those used after Interior Gateway Protocol (IGP) convergence. The proposed mechanism can address all single link, node, and SRLG failures in an area; moreover it is an efficient solution to protect against BGP ASBR failures as well as VPN PE router failures. IPFRR-FN can be a supplemental tool to provide FRR when LFA cannot repair a failure case, while it can be a replacement of existing ASBR/PE protection mechanisms by overcoming their scalability and complexity issues.