The MPLS WG Archive

["Eric Osborne" <eosborne@cisco.com>]

 > -----Original Message-----
 > From: owner-mpls@UU.NET [mailto:owner-mpls@UU.NET] On Behalf 
 > Of Alexander Attsik
 > Sent: Tuesday, April 13, 2004 6:51 AM
 > To: MPLS wg
 > Subject: Are RSVP-TE messages labeled?
 > 
 > 
 > Another question about MPLS-TE.
 > Are IP-packets, carrying RSVP (TE) messages (e.g. Path, 
 > Resv), sent labeled in MPLS-TE domain? 
 > 

No, at least not in the implementation I'm familiar with.

 > Path message with ERO object could be sent with label = 1 
 > (RouterAlert)  forcing neighbour LSR to examine ERO. 
 > Analogously it is possible to send Path without a label, but 
 > only with IP-header with  Router Alert Option.
 > 

Sure, but why?  For both Path and Resv, all RSVP messages are destined for
the device on the other end of the link, so label-switching (basically
router-alert with imp-or exp-null underneath) seems a waste of time and
energy.
 
 > Resv's destination address is next hop, is there a reason to 
 > label this message for such transmission? 

None that I can see.

 > On the other hand 
 > use of labeled RSVP-TE messages make message transmission 
 > unified all over MPLS domain. (Except for LDP and IGP, I suppose).
 > 

What exactly is "unified message transmission"?  And excepting LDP and RSVP
from MPLS signalling, aren't you only left with BGP?  Targeted LDP sessions
nonwithstanding, I suppose.



eric

 > I'll be very grateful for your help.
 > 
 >                                                              
 >                                        Alexander Attsik
 > 
 >