MPLS LDP inbound-FEC filtering filters inbound label bindings on a MPLS router. You can control the amount of memory and CPU processing involved in installing and advertising label bindings not used for forwarding.
MPLS LDP inbound-FEC filtering also serves as a tool to avoid DOS attack. By creating a prefix-list, and specifying prefixes label mappings, the forwarding plane accepts and installs the label bindings. The prefix-list is applied to an individual LDP session or globally to all the LDP sessions.