Subject: [Pce] When LSP belongs to multiple association groups of the same association type...

From: Dhruv Dhody <[email-masked]>
Date: Fri, 12 Jul 2019 20:48:33 +0530

Hi Authors, WG,

Please refer to this exchange with Benjamin regarding
draft-ietf-pce-association-group

--

>    Multiple types of associations can exist, each with their own
>    association identifier space.  The definition of the different
>    association types and their behaviours is outside the scope of this
>    document.  The establishment and removal of the association
>    relationship can be done on a per LSP basis.  An LSP may join
>    multiple association groups, of different or of the same association
>    type.
>
> Is it possible for an LSP to join multiple association groups of the same
> type and then for configuration to be assigned to two groups in a manner
> that conflicts?  What procedure is used for conflict resolution in such a
> case?
>
[[Dhruv Dhody]] This should be handled per association type. I will
make sure that future documents that define association types include
text for this.

--

We should update the I-Ds that define association types to include text on
what should be done when an LSP tries to join multiple association group of
the same association-type? And if it is allowed, what to do in case of
conflicts.

There are cases where taking this input into account is straightforward.
Multiple association of a given type may either be natively supported (e.g.,
the diversity I-D already mentions it) or obviously excluded (e.g., the
bidirectional association falls into this kind).  Sometimes, the resulting
behavior may require more specification on failure techniques: e.g., what
should a PCC do if requested a 1:3 protection while it only supports dedicated
protection?

Request the authors to think about this and make suitable update based on the
individual association type. The post WGLC I-Ds could be updated as part of
directorate review update.

Thoughts?

Thanks!
PCE Chairs