Re: Comment on draft-shiomoto-ccamp-gmpls-mrn-reqs-00.txt

["Adrian Farrel" <adrian@olddog.co.uk>]

Hi Stephen,

> I was not able to be at the CCAMP meeting today but do have some comments on
> draft-shiomoto-ccamp-gmpls-mrn-reqs-00.txt

Glad you were able to review the draft. Thanks for taking the time.
The slides for this and the other CCAMP drafts discussed at the meeting can be found at
http://www.olddog.co.uk/61/ccamp.htm

> It seems that the goals of the draft could be accomplished more simply by
> adopting the layer architecture as defined in ITU-T Recommendations G.805
> and G.809.  By doing this, the specific boundaries between TDM, LSC, etc.
> don't have to be articulated as they are just layer networks.  Also, the
> designation of TDM does not include the notions of the layers within that
> (e.g., DS3, STS-1, VC4, etc.) which are important to transport equipment.
> Adopting the layer architecture also enables a client layer to be supported
> by an inverse multipling layer such as provided by Virtual Concatenation.
> Here a layer of finer granularity is use to support a layer of coarser
> granularity.

Thank you for the pointer to G.805 and G.809.  It is very important to attempt to align
the terminologies so that we can discover whether the architectures are the same and
whether they are trying to address the same problem space. It is also always good to try
not to reinvent the wheel.

As you have no doubt noticed, the GMPLS architecture and problem space require the
capability to signal and route across multiple instances of what the ITU-T terms a
transport layer. We would gladly look at any architecture you have in this space. Can you
point us at the ITU-T document(s) that describe the architecture and solutions for routing
and signaling across multiple layers?

Thanks,
Adrian

PS As pointed out by several people in other emails, I'm not sure if we mean exactly the
same thing when we say multi-region
and multi-layer. It would be valuable if you could read the GMPLS architecture RFC and the
hierarchy draft and comment on whether you see these terms in the IETF context as matching
perfectly with ITU-T terms.