TCP/UDP port 646

dppagc

A bit of confusion i have here

Is the router that initiate the ldp session dependent on whether it is the highest loopback id or is it based on the port number 646?

EdTheLad

LDP by default advertises its RID as the transport address, the RID can be explicitly configured or the highest loopback, or if no loopback highest interface ip. The highest ip address between peers becomes active for the tcp session, the active side will have a src port of 646.