I've seen the transport address being used in some cases where the LDP router-ID is not advertised in IGP (for whatever reason), but these were corner cases..
I've had to use it when there were vendor interop-problems, the LDP session wouldn't come up otherwise. I even posted to the IETF MPLS list regarding the fact that I couldn't figure out where in the standard it was said what address should be used where, but I received no reply so I am still none the wiser how it should work so I know what vendor to tell to go fix their stuff.
-- Mikael Abrahamsson email: [EMAIL PROTECTED] _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
