RE: last call comment on draft-ietf-ccamp-gmpls-sonet-sdh-00.txt

["Mannie, Eric" <Eric.Mannie@ebone.com>]

Hello Alan,

>The LSP Hierarchy draft introduces Link Mux Capability.  There is a value
>defined for TDM Switch Capable.  In order to support the hierarchy in the
>above paragraph, TDM Switch Capable would need to be split into multiple
>values, one for each level of the SDH/SONET multiplexing structure.

The text that you indicated don't restrict to only two levels, you could
open an LSP inside an LSP, inside an LSP, etc... The example was given with
two levels. The important point is that whatever is the LSP that you want to
open you have a higher part and a lower part. So we don't have to define
plenty of different labels, not only per layer (higher order versus lower
order) but also as a whole since we could want to directly indicate a VC-11
in the whole multiplex (in that case the full label is significant). Having
different labels makes it much more complex without adding any additional
functionality.

Kind regards,

Eric

-----Original Message-----
From: Kullberg, Alan [mailto:akullber@netplane.com]
Sent: Thursday, May 24, 2001 5:44 PM
To: Mannie, Eric; 'Kireeti Kompella'
Cc: 'ccamp@ops.ietf.org'; 'mpls@UU.NET'
Subject: last call comment on draft-ietf-ccamp-gmpls-sonet-sdh-00.txt


The following paragraph is from section 3 of
draft-ietf-ccamp-gmpls-sonet-sdh-00.txt.

  When hierarchical SDH/SONET LSPs are used, an LSP with a given
   bandwidth can be used to tunnel lower order LSPs.  The higher
   order SDH/SONET LSP behaves as a virtual link with a given
   bandwidth (e.g. VC-3), it may also be used as a Forwarding
   Adjacency. A lower order SDH/SONET LSP can be established through
   that higher order LSP. Since a label is local to a (virtual) link,
   the highest part of that label is non-significant and is set to
   zero.

The LSP Hierarchy draft introduces Link Mux Capability.  There is a value
defined for TDM Switch Capable.  In order to support the hierarchy in the
above paragraph, TDM Switch Capable would need to be split into multiple
values, one for each level of the SDH/SONET multiplexing structure.

What do you think?

Alan