Preferential Forwarding Status bit definition

This document describes a mechanism for standby status signaling of redundant PWs between their termination points. A set of redundant PWs is configured between PE nodes in SS-PW applications, or between T-PE nodes in MS-PW applications. In order for the PE/T-PE nodes to indicate the preferred PW path to forward to one another, a new status bit is needed to indicate a preferential forwarding status of active or standby for each PW in the redundancy set. This draft specifies a new PW status bit for this purpose.