This feature provides the capability to specify the label stack of the return path from the S-BFD reflector to the S-BFD initiator on the S-BFD initiator, which can be a different path from the shortest/best IGP path from the S-BFD reflector back to the S-BFD initiator, in order that the forwarding of the S-BFD packets would not be impacted by IP routing convergence, i.e., the stability of S-BFD session is not impacted by the IP routing convergence time. 

This feature monitors the BGP session status. When a BGP session goes down, traffic originally forwarded to the next hops learned from the downed BGP peer is quickly diverted to a backup path if any, or in the case of ECMP, remaining ECMP members.