The MPLS WG Archive

[schultz@io.iol.unh.edu]

Hello,

I apologise if you receive this email twice, I sent it 10 days ago and it
has not yet been posted.

I assume that the Srefresh message is a local exchange between two LSRs
however, I can not find the specifics of this.  From my understanding of
RSVP, a router will always know it's neighbor's IP address once RSVP
messages have been exchanged due to the PHOP object.

RFC 2961 Section 4 states:
"Message identification and acknowledgment is done on a per hop basis."

This implies that the Message_Identifier is generated locally.

RFC 2961 section 5.2 states:
"Srefresh messages that are addressed to a session's destination IP
address MUST be sent with the Router Alert IP option in their IP headers.
Srefresh messages addressed directly to RSVP neighbors SHOULD NOT be sent
with the Router Alert IP option in their IP headers."

Is this piece referring to the penultimate hop, or to potential end to end
communication?

Is the MESSAGE_ID object generated at the ingress/egress router, or is it
generated locally?  (I believe it is, but...)

Is it legal to send Srefresh messages end to end in the network?

I suspect that both MESSAGE_ID and Srefresh messages are generated locally
(like Bundle messages), but I can not find a place in the RFC that
specifies this.  I can't think of a situation where the Srefresh message
would be addressed directly to RSVP neighbors.  If this situation exists,
please explain it.

Please let me know what you think.

Thanks,
-Ben