With increasing deployment of Loop-Free Alternates (LFA) [RFC5286], it is clear that a complete solution for IP and LDP Fast-Reroute is required. This specification provides that solution. IP/LDP Fast- Reroute with Maximally Redundant Trees (MRT-FRR) is a technology that gives link-protection and node-protection with 100% coverage in any network topology that is still connected after the failure. MRT removes all need to engineer for coverage. MRT is also extremely computationally efficient. For any router in the network, the MRT computation is less than the LFA computation for a node with three or more neighbors.