Re: [CCAMP] Moving the WSON discussion forward (Was Re: TR: New Version Notification fordraft-peloso-ccamp-wson-ospf-oeo-03.txt)

[Greg Bernstein <[e-mail]>]

Hi CCAMPers, none of the changes to the current WSON WG drafts listed 
below are necessary to achieve the stated goals, i.e., the current 
mechanisms suffice please see details below. We can offer an offline 
tutorial session to interested parties in Quebec city as it seems there 
is a lack of understanding of (a) the current WSON drafts, and (b) GMPLS 
protocols in general.

Best Regards
Greg

On 7/4/2011 8:02 AM, PELOSO, PIERRE (PIERRE) wrote:
> Hello CCAMPer's,
>
> Following Lou's suggestion, this email intends to summarize the main changes introduced by draft-peloso-ccamp-wson-ospf-oeo, viewed from the information model, we end-up with 3 of them:
>      0. IMPORTANT REMINDER OF ONE OF THE PIECES THAT WAS NOT CHANGED: Resource block = group of devices with same features and same connectivity constraints.
>
>      1. Introduction of the Resource Pool entity inside the model, which allows the definition of several resource entites per node independantly floodable.
> MOTIVATION: to decrease the size of flooding upon LSP changes (setup or tear down). (Resource Pool = group of resource blocks with same connectivity constraints)
--> There is already a standard mechanism in OSPF-TE for achieving this 
(multiple LSA instances) which is already in common use in MPLS and 
GMPLS so this change is unneeded. The current WSON encoding model 
includes very fine granularity in sub-TLVs hence this change would not 
achieve the stated "MOTIVATION" any better than the current approach.
>      2. Use of the connectivity matrix defined inside the node entity in order to describe connectivity constraints between node-external links and the resource pools.
> MOTIVATION: a/ to gather static information inside node entity (for OSPF-TE inside a LSA never flooded upon LSP updates). b/ to limit the number of connectivity representations introduced by current extensions (draft-ietf-rwa-info proposes similar TLVs in different LSAs).
>
--> This change mixes information from "general constraints" with "wson 
specific constraints" and hence goes against the decision made by the 
CCAMP WG at the March 2009 San Francisco IETF. This proposed change does 
not result in any space savings and results in an undesirable mixing of 
separate concepts.  All current WSON drafts include separation of 
relatively "static" from more "dynamic" information, hence this change 
is unnecessary.
>      3. Reduction of the scope of Resource Block Information, to keep only resource/device description (moved the number of devices away).
> MOTIVATION: a/ to share resource description for all the (same devices) blocks (of a node), then decreasing the total size of information. b/ to create an independent flooding entity holding all the resource descriptions (which are static), the decreasing the size of updated information.
--> This change (a) does not result in any size savings, and (b) is not 
necessary to "to create an independent flooding entity holding all the 
resource descriptions".  Resource block information is already a 
separate sub-TLV and the current resource block set mechanism provides a 
highly efficient method to indicate which resources blocks are 
associated with a particular type of resource.


> Best regards,
>
> Cyril, Giovanni, Julien and Pierre
>
> -----Message d'origine-----
> De : [e-mail] [mailto:[e-mail]] De la part de Lou Berger
> Envoyé : mardi 28 juin 2011 16:57
> À : Leeyoung; [e-mail]
> Cc : [e-mail]
> Objet : [CCAMP] Moving the WSON discussion forward (Was Re: TR: New Version Notification fordraft-peloso-ccamp-wson-ospf-oeo-03.txt)
>

-- 
===================================================
Dr Greg Bernstein, Grotto Networking [phone]