Topology Independent Fast Reroute using Segment Routing
Cisco Systems
Cisco Systems
Orange
Orange
Individual Contributor
This document presents Topology Independent Loop-free Alternate Fast Re-route (TI-LFA), aimed at providing protection of node and adjacency segments within the Segment Routing (SR) framework. This Fast Re-route (FRR) behavior builds on proven IP-FRR concepts being LFAs, remote LFAs (RLFA), and remote LFAs with directed forwarding (DLFA). It extends these concepts to provide guaranteed coverage in any IGP network. A key aspect of TI-LFA is the FRR path selection approach establishing protection over post-convergence paths from the point of local repair, dramatically reducing the operational need to control the tie-breaks among various FRR options.