Both inbound and outbound LDP label binding filtering is supported.
Inbound filtering (import policy) allows configuration of a policy to control the label bindings an LSR accepts from its peers. Label bindings can be filtered based on:
Neighbor: Match on bindings received from the specified peer
Prefix-list: Match on bindings with the specified prefix/prefixes
The default import behavior is to accept all FECs received from peers. The LDP export policy can be used to explicitly add FECs (or non-LDP routes) for label propagation and does not filter out or stop propagation of any FEC received from neighbors.
Export policy enables configuration of a policy to advertise label bindings based on:
Direct: All local subnets
Prefix-list: Match on bindings with the specified prefix or prefixes
The LDP export policy will not filter out FECs. It is only used to explicitly add FECs (or non-LDP routes) for label propagation.
The default export behavior originates label bindings for system address and propagate all FECs received.