Subject: Progressing MAM

From: "Francois Le Faucheur (flefauch)" <[email-masked]>
Date: Fri, 7 Mar 2003 13:41:15 -0000

All,

Now that we have closed on the BC Model approach and decided to document
both the Russian Dolls Model and the Maximum Allocation Model in
separate documents, we need an "official" document for MAM
specification.

Although discussed in a number of I-Ds, MAM was only:
    - defined very succinctly in the diff-te-reqts draft
    - discussed in drafts providing some elements of analysis of the
merits/shortcomings of various models.

This is why I put together a diff-te-mam- draft which is the "mirror
draft" of the Russian Dolls draft (diff-te-russian). This draft aims at
giving a short yet exhaustive specification of MAM (including case where
Local Overbooking is used), examples of CAC formulas to make everything
really unambiguous and include a brief highlight of the main properties
of this model using the WG conclusions that were reached on the mailing
list on this very point.
I would not expect any of its content to be controversial.

I would like to get a sense of the list about using this document as the
basis for the WG MAM specification and for accepting this as a WG
document. Thoughts anyone?

The material providing analysis of the various merits/shortcomings of
various models is very useful stuff for the WG, but I would suggest
keeping this information in a document separate from the MAM
specification. Rationale include:
    - MAM definition has been thoroughly discussed/agreed in WG and
could be finalised very quickly, while detailed analysis still requires
more WG time.
    - pros/cons analysis is of informational nature while the MAM
specification has MUST/SHOULD.

Cheers

Francois

>> 
>> Title : Maximum Allocation Bandwidth 
>> Constraints Model for 
>> Diff-Serv-aware MPLS Traffic Engineering
>> Author(s) : F. Le Faucheur
>> Filename : draft-lefaucheur-diff-te-mam-00.txt
>> Pages : 8
>> Date : 2003-2-25
>> 
>> This document provides specification for one Bandwidth Constraints 
>> model for Diff-Serv-aware MPLS Traffic Engineering, which is 
>> referred 
>> to as the Maximum Allocation Model.
>> 
>> A URL for this Internet-Draft is: 
http://www.ietf.org/internet-drafts/draft-lefaucheur-diff-te-mam-00.txt

---

From: "Ash, Gerald R (Jerry), ALABS" <[email-masked]>
Date: Fri, 7 Mar 2003 09:40:28 -0500

> document. Thoughts anyone?

There is another proposed MAM specification draft at http://www.ietf.org/internet-drafts/draft-wlai-tewg-bcmodel-01.txt.  This I-D  should also be considered for the MAM specification.  I believe it would be best to combine the efforts into a unified specification draft.
 
> could be finalized very quickly, while detailed analysis 
> still requires more WG time.

I disagree.  The pros/cons analysis should be an integral part of the specification (as in an Appendix) to provide critical guidance to users' implementation of the models in their networks.  There are some very important guidelines which users should be aware of before choosing a BC model for their network.  

Unless this essential information is progressed together with the specification, it may well get lost, delayed, or at least be hard for users to come by.  We already have analysis already in hand in http://www.ietf.org/internet-drafts/draft-wlai-tewg-bcmodel-01.txt, so there should be no delay caused by its inclusion or need for more WG time.  There is no down-side to including the analysis in an Appendix to the specification.

Furthermore, the Russian Doll BC specification draft http://www.ietf.org/internet-drafts/draft-ietf-tewg-diff-te-russian-01.txt lacks this kind of critical analysis, which should be added before the draft goes forward (will post this comment when RD specification goes to last call).

Jerry

---

From: "Lai, Wai S (Waisum), ALABS" <[email-masked]>
Date: Fri, 7 Mar 2003 18:15:13 -0500

The Requirements draft calls for a consideration of BC model selection
criteria.  I believe that any specification documents, including RDM,
MAM, or MAR, should provide proper and adequate coverage of these
criteria before they can be ready for WG Last Call.
Thanks, Wai Sum

-----Original Message-----
From: Francois Le Faucheur (flefauch) [mailto:[email-masked]]
Sent: Friday, March 07, 2003 8:41 AM
To: Jim Boyle; Ed Kern (ejk); [email-masked]
Subject: Progressing MAM

All,

Cheers

Francois

---

From: "Choudhury, Sanjaya" <[email-masked]>
Date: Mon, 10 Mar 2003 09:57:21 -0500

Hi! In my opinion, the most interesting part of the draft
"draft-wlai-tewg-bcmodel-01" lies in the Appendix (and not
in the brief specification of the MAM). May be the authors,
should consider presenting this document as a comparative
study/analysis of existing BC Models.

Although, the detailed (comparative) analysis of different
BC Models is quite useful, I am not sure it belongs in the
individual BC Model specification (Are we going to add this
as an appendix to all BC Model Specifications?)

Thanks,
sanjay

> From: Ash, Gerald R (Jerry), ALABS [mailto:[email-masked]]
> Sent: Friday, March 07, 2003 9:40 AM
> To: [email-masked]
> Cc: Ash, Gerald R (Jerry), ALABS; Lai, Wai S (Waisum), ALABS; Francois
> Le Faucheur (flefauch); Jim Boyle; Ed Kern (ejk)
> Subject: RE: Progressing MAM
> 
> 
> There is another proposed MAM specification draft at 
> http://www.ietf.org/internet-drafts/draft-wlai-tewg-bcmodel-01
> .txt.  This I-D  should also be considered for the MAM 
> specification.  I believe it would be best to combine the 
> efforts into a unified specification draft.
>  
> I disagree.  The pros/cons analysis should be an integral 
> part of the specification (as in an Appendix) to provide 
> critical guidance to users' implementation of the models in 
> their networks.  There are some very important guidelines 
> which users should be aware of before choosing a BC model for 
> their network.  
> 
> Unless this essential information is progressed together with 
> the specification, it may well get lost, delayed, or at least 
> be hard for users to come by.  We already have analysis 
> already in hand in 
http://www.ietf.org/internet-drafts/draft-wlai-tewg-bcmodel-01.txt, so there
should be no delay caused by its inclusion or need for more WG time.  There
is no down-side to including the analysis in an Appendix to the
specification.

Furthermore, the Russian Doll BC specification draft
http://www.ietf.org/internet-drafts/draft-ietf-tewg-diff-te-russian-01.txt
lacks this kind of critical analysis, which should be added before the draft
goes forward (will post this comment when RD specification goes to last
call).

Jerry

---

From: "Francois Le Faucheur (flefauch)" <[email-masked]>
Date: Thu, 13 Mar 2003 13:48:44 -0000

Hello,

>> From: Choudhury, Sanjaya [mailto:[email-masked]] 
>> Sent: 10 March 2003 15:57
>> To: 'Ash, Gerald R (Jerry), ALABS'; [email-masked]
>> Cc: Lai, Wai S (Waisum), ALABS; Francois Le Faucheur 
>> (flefauch); Jim Boyle; Ed Kern (ejk)

I support Sanjaya's suggestion. I also believe it would be very
beneficial to progress tewg-bcmodel into a document focusing on the BC
Model comparisons. Perhaps it could be the base for a "BC Model
Applicability Statement"  (ie when is this model more applicable than
this one).
Cheers
Francois

>> http://www.ietf.org/internet-drafts/draft-wlai-tewg-bcmodel-0
1.txt, so there
should be no delay caused by its inclusion or need for more WG time.
There
is no down-side to including the analysis in an Appendix to the
specification.

Furthermore, the Russian Doll BC specification draft
http://www.ietf.org/internet-drafts/draft-ietf-tewg-diff-te-russian-01.t
xt
lacks this kind of critical analysis, which should be added before the
draft
goes forward (will post this comment when RD specification goes to last
call).

Jerry