Editing Label Distribution Protocol (section)

==T-LDP==

Targeted LDP sessions are different because during the discovery phase hellos are unicast to the LDP peer rather than using multicast. A consequence of this is that tLDP can be set up between non-directly connected peers whereas non-targeted LDP peers must be on the same subnet. tLDP may still be used between connected peers if desired.

On a router running TiMOS when an SDP (Service Distribution Path) is configured, automatic ingress and egress labeling (targeted LDP) is enabled by default and ingress and egress "service" labels are signaled over a TLDP connection. If signaling is turned off on an SDP, ingress and egress “service” labels must be manually configured when the SDP is bound to a service.{{citation needed|date=April 2019}}