[netmod] Opstate solutions discussions: update and request for WG input

[Lou Berger <[e-mail]>]

All,

We want to provide an update based on the off line discussions
related to OpState Solutions that we have been having and solicit
input from the WG.

All authors of current solution drafts [1,2,3] together with those
who helped conduct the solutions analysis* were invited to the these
discussions -- with the objective of coming up with a single
consolidated proposal to bring to the WG. (I/Lou acted as facilitator
as Kent and Juergen were and are involved with the technical details.)

The discussions have yielded some results but, unfortunately,
not a single consolidated proposal as hoped, but rather two
alternate directions -- and clearly we need to choose one:

    1) Adopt the conventions for representing state/config
       based on Section 6 of [1].

       From a model definition perspective, these conventions
       impact every model and every model writer.

    2) Model OpState using a revised logical datastore definition
       as introduced in [4] and also covered in [5]. There is
       also a variant of this that we believe doesn't significantly
       impact this choice.

       With this approach, model definitions need no explicit
       changes to support applied configuration.

>From a technology/WG standpoint, we believe an approach
that doesn't impact every model written (i.e., #2) is superior.
The counterpoint to this is that the conventions based
approach (i.e., #1) is available today and being followed in
OpenConfig defined models.

We would like to hear opinions on this from the WG before
declaring one of the following as the WG direction:

    A) models that wish to support applied configuration MUST
       follow conventions based on [1] -- and the WG needs to
       formalize these conventions.
or
    B) no explicit support is required for models to support
       applied configuration -- and that the WG needs to
       formalize an opstate solution based on the approach
       discussed in [4] and [5].

We intend to close on this choice before Berlin.

Thank you,
Lou (and co-chairs)

[1] https://tools.ietf.org/html/draft-openconfig-netmod-opstate-01
[2] https://tools.ietf.org/html/draft-kwatsen-netmod-opstate-02
[3] https://tools.ietf.org/html/draft-wilton-netmod-opstate-yang-02
[4] https://tools.ietf.org/html/draft-schoenw-netmod-revised-datastores-00
[5] https://tools.ietf.org/html/draft-wilton-netmod-refined-datastores-00
* - Chris H. and Acee L.