FEC to NHLFE (FTN)

The "FEC to NHLFE" (FTN) maps each FEC to a set of NHLFE's. It is used for forwarding packets that arrive unlabeled i.e packets received from outside the MPLS domain at the ingress (or received from a higher layer), but which are to be labeled before being forwarded.

As in the case of an ILM-to-NHLFE map, if the FTN entry for a packet maps to a set of NHLFE's that contains more than one element, exactly one element of the set must be chosen before forwarding the packet. Having a set of NHLFE's mapped from a label in FTN is desirable in certain cases e.g in order to provide load balancing we could have multiple paths.