Subject: Re: [Fwd: draft-ietf-pwe3-control-protocol-02.txt]

From: "W. Mark Townsley" <[email-masked]>
Date: Sat, 22 Mar 2003 21:23:56 +0100

Eric Rosen wrote:
> David> The  draft currently  uses  label withdraw  as  a fault  notification
> David> mechanism.
> 
> I agree that label withdrawal is a poor fault notification method, as it has
> various side-effects which may not be desired (as David indicates).
> 
> If the  control plane is used  to pass status, it  might be better  to use a
> "status"  TLV,  such  as  is proposed  in  draft-shah-pwe3-control-protocol-
> extension-00.txt.  This eliminates a lot of the unpleasant side-effects. 
> 
> If it is desired to pass status or fault information reliably, passing it in
> the control plane may be better, as the data plane does not provide reliable
> transport.   Note also  that passing  the info  in the  data plane  does not
> necessarily preserve the  sequencing of the fault info  with the data, since
> the data is not necessarily sequenced.  

This is what we do in the L2TPv3 draft now. A "Circuit Status" AVP is defined 
and included in PW setup messages for conveying initial circuit status, and 
included in the SLI control message if the status changes over the life of the 
PW. It works well for us.

- Mark

> 
> 
> 
> 
> _______________________________________________
> pwe3 mailing list
> [email-masked]
> https://www1.ietf.org/mailman/listinfo/pwe3
>