Subject: Doubt on LSP Modification Using CR-LDP draft

From: "Nagabhushana Ramaswamy Nadig" <[email-masked]>
Date: Tue, 30 Oct 2001 15:29:31 +0400 (RET)

Hi all,
     In draft draft-ietf-mpls-crlsp-modify-03.txt, it was given the method
for modifying the existing CRLSP to Increase/Decrease Bandwidth.
     Here it specifies that the Modify has to allocate new labels, but
reserves the Difference Bandwidth only. Also the ingress will switch the
traffic to the new Label, so that the transition would be smooth.
      I have doubt regarding using new label, but reserving only difference
BandWidth. When I install label binding in the Link layer ( say, in FR, I
create PVC using two end points with incoming and outgoing DLCIs on the
incoming and outgoing port respectively), I have to specify the Reservation.
Now, if I have 2 label pairs, its like I have 2 PVCs in the link layer.
      Also Draft says that Ingress will switch data to the new path before
it releases the old one. Thus my  Transit node should have both the
connections active at the same time for smooth transition ( and they are 2
different connections for the link layer). Now, with the different BW
reservation on the second PVC, how the traffic can be transmitted ?, when
can I allocate the BW reserved for the first PVC to the modified PVC without
affecting the Data flow ?

Thanks in advance,
Bhushana