The MPLS WG Archive

["Feng, Mark" <m_feng@trillium.com>]

When the receiver receives the new Path message, it triggers a state change.
A new Resv message will be sent out, with the new sender added. 

When the transit nodes process the new Resv message, since there is a new
sender in the Resv message, it also triggers a state change. Resv message
will then be sent out at each of the transit node. 

If the new path tranverses through different nodes, at the new nodes, the
Resv message also triggers a state change, since it is new, resulting in the
Resv message being sent out.

In other words, the Resv message is not absorbed anywhere, as you suggested.

Samething applies to increase of bandwidth.

Hope this helps.

-Mark

> -----Original Message-----
> From: Rajesh P Jain [mailto:rpjain@sasken.com]
> Sent: Monday, August 13, 2001 8:00 AM
> To: MPLS UUNET Mailing List; mpls-ops@mplsrc.com
> Subject: Doubt on Make Before Break Concept
> 
> 
> Hi,
>                     I have some doubts on Smooth Re-Routing of LSP
> Tunnels.
> 
> 1. As I understand the draft, the make-before-break (Smooth 
> Re-Routing)
> should be initiated by the Sender Node (Path Message is sent new with
> new ERO object and ofcourse with a different LSP ID in the
> SENDER_TEMPLATE ). The receiver receives this Path Message.
> 
> 2. Now, the receiver HAS to send a RESERVE message with SE reservation
> style (Of course with Filter spec list containing the 
> SENDER_TEMPLATE of
> the old Path Message and SENDER_TEMPLATE of new Path Message i.e they
> differ only in their LSP ID's, and of course ERO's).
> 
> 3. Now, the New Path Message received  is AS GOOD AS A New Sender for
> this receiver and hence it MAY NOT send a RESERVE Message for this
> sender (The receiver sends only if it wants some reservation for this
> sender).
> 
> 4. In case, if the receiver chooses not to send the reserve message,
> then Smooth Re-Route WILL NOT happen.
> 
>                     So, can anyone explain whether the Smooth 
> Re-Routing
> is Sender-Based  or Receiver -Based (Who has the control of Re-Routing
> the traffic ??) ???
> 
>                     In case of Increase in Band-width (For a 
> particular
> LSP), the Sender indicates the increase in band-width BUT still the
> Receiver HAS to send the Reserve message for this increase in the
> Band-width. So, the same problem holds good for this case also????
> 
>                     Am I missing something???? Please throw light on
> this issue possibly with an example.
> 
> TIA
>         Rajesh P Jain
> 
> 
> 
>