Re: Last Call: <draft-ietf-teas-yang-te-topo-15.txt> (YANG Data Model for Traffic Engineering (TE) Topologies) to Proposed Standard

[Xufeng Liu <[e-mail]>]

Hi Tom,

Agree what you said. We have brought this issue up in the NETMOD WG, but
our proposal got shot down.

https://mailarchive.ietf.org/arch/browse/netmod/?q=augment+grouping

We will try again later, but this is what we have for now.

Thanks,
- Xufeng

On Tue, Jun 19, 2018 at 7:11 AM, tom p. <[e-mail]> wrote:

> I just got a sight of where this I-D leads to and find it challenging.
>
> This I-D provides a template in Appendix C for other technologies to use
> to augment the base YANG module:
>
> draft-ietf-ccamp-otn-topo-yang
>
> is such a technology and the YANG module therein consists of about 90
> statements of the form
>
>   /* Augment label hop of route-include of connectivity-matrices (added)
> */
>   augment "/nw:networks/nw:network/nw:node/tet:te/"
>         + "tet:te-node-attributes/tet:connectivity-matrices/"
>         + "tet:optimizations/tet:algorithm/tet:metric/"
>         + "tet:optimization-metric/"
>         + "tet:explicit-route-include-objects/"
>         + "tet:route-object-include-object/"
>         + "tet:type/tet:label/tet:label-hop/"
>         + "tet:te-label/tet:technology" {
>     when "../../../../../../../../../../../../../../"
>        + "nw:network-types/tet:te-topology/"
>        + "otntopo:otn-topology" {
>       description "Augment OTN TE label";
>     }
>     description "OTN label.";
>     case otn {  uses otn-types:otn-path-label; }
>   }
>
> The YANG tree diagram, which is 'used to provided a simplified graphical
> representation of a data model' runs to 15 pages and is almost harder to
> follow.
>
> It does seem to me that something has gone wrong here, with the
> capabilities of YANG or the way it is used or ...  My knowledge of YANG
> is not enough to know whether or not there is a different approach in
> this I-D which would make the augmenting module easier to understand
> (e.g. a data tree of fewer than 20 levels, use of relative XPath paths
> or replacing 'when' with 'if-feature') but it does seem that what we
> have now is hard to review in a meaningful way.  Yes, tools can tell us
> that the augmenting module is syntactically correct but whether or not
> it does what is says on the tin I find very hard to form a view on.
>
> Tom Petch
>
>
> ---- Original Message -----
> From: "tom p." <[e-mail]>
> To: "tom p." <[e-mail]>; <[e-mail]>
> Cc: <[e-mail]>; <[e-mail]>;
> <[e-mail]>; <[e-mail]>
> Sent: Wednesday, June 06, 2018 10:26 AM
>
> > Further thoughts on -16 (as my previous comments included below are).
> >
> > What is the status of Appendix B?  I find this a thorny question.
> > Appendices are usually regarded as not Normative, with a statement
> > called for when it is otherwise.  This is a YANG module which non-NMDA
> > servers will implement so that says it is Normative, to me.  On the
> > other hand, the world is going NMDA - I do not know how fast - so this
> > is more like Historic; or non-Normative?
> >
> > I do not know the answer but do know we can expect to see this several
> > times, so I am thinking that some thought and guidance from an Ops AD
> > would be valuable.
> >
> > IANA Considerations should have a
> >       reference:    RFC XXXX
> > for each module registered
> >
> > Additionally, my comments about the YANG module in the body of the
> > document apply to Appendix B and C namely
> > - [RFC ... looks wrong in a YANG module
> > - import without reference
> >
> > Does the YANG module in Appendix C need a Copyright statement?
> >
> > Should the YANG module in Appendix C be registered?  It took a while
> for
> > the IETF to see the need to define formally such things as
> > example.com
> > so I am thinking it probably should be lest we get many different
> > varieties in the wild.
> >
> > And I would like a Note to the RFC Editor asking them to update the
> > dates with the date of publication especially since there are five
> such
> > dates rather than the usual two.
> >
> > Tom Petch
> >
> > ----- Original Message -----
> > From: "tom p." <[e-mail]>
> > To: <[e-mail]>
> > Cc: <[e-mail]>; <[e-mail]>;
> > <[e-mail]>; <[e-mail]>
> > Sent: Tuesday, June 05, 2018 6:01 PM
> >
> >
> > > Lou et al
> > >
> > > I note that the YANG module in this I-D has Reference statements to
> 20
> > > other RFC, which is good, but only one of the twenty appear in the
> > > References for the I-D, which I think is not good, and needs to be
> > > fixed.
> > >
> > > Also, some of the RFC which appear in Reference clauses of the YANG
> > > module appear in [square brackets] e.g. [RFC6001] which I think
> should
> > > not be there.
> > >
> > > In the same vein, there are imports of four other YANG modules but
> no
> > > indication as to which RFC they can be found in - again, I think
> that
> > > that needs fixing with a Reference statement.
> > >
> > > A quick pass suggests the missing references are to
> > > 1195 missing
> > > 3209 missing
> > > 3272 missing
> > > 3471 missing
> > > 3630 missing
> > > 3785 missing
> > > 4201 4202 4203 4206 all missing
> > > 4872 missing
> > > 5152 missing
> > > 5212 missing
> > > 5305 missing
> > > 6001 missing
> > > 6241 ok Norm
> > > 7471 missing
> > > 7752 missing
> > > 7579 missing
> > >
> > > Russ's comment about Section 1.1 does not seem to have been
> addressed.
> > >
> > > Tom Petch
> > >
> > >
> > > ----- Original Message -----
> > > From: "The IESG" <[e-mail]>
> > > To: "IETF-Announce" <[e-mail]>
> > > Cc: <[e-mail]>; <[e-mail]>;
> > > <[e-mail]>; <[e-mail]>
> > > Sent: Wednesday, May 16, 2018 3:40 PM
> > >
> > > > The IESG has received a request from the Traffic Engineering
> > > Architecture and
> > > > Signaling WG (teas) to consider the following document: - 'YANG
> Data
> > > Model
> > > > for Traffic Engineering (TE) Topologies'
> > > >   <draft-ietf-teas-yang-te-topo-15.txt> as Proposed Standard
> > > >
> > > > The IESG plans to make a decision in the next few weeks, and
> > solicits
> > > final
> > > > comments on this action. Please send substantive comments to the
> > > > [e-mail] mailing lists by 2018-05-30. Exceptionally, comments
> > may
> > > be
> > > > sent to [e-mail] instead. In either case, please retain the
> > > beginning of
> > > > the Subject line to allow automated sorting.
> > > >
> > > > Abstract
> > > >
> > > >
> > > >    This document defines a YANG data model for representing,
> > > retrieving
> > > >    and manipulating Traffic Engineering (TE) Topologies. The model
> > > >    serves as a base model that other technology specific TE
> Topology
> > > >    models can augment.
> > > >
> > > >
> > > >
> > > >
> > > >
> > > > The file can be obtained via
> > > > https://datatracker.ietf.org/doc/draft-ietf-teas-yang-te-topo/
> > > >
> > > > IESG discussion can be tracked via
> > > >
> > https://datatracker.ietf.org/doc/draft-ietf-teas-yang-te-topo/ballot/
> > > >
> > > >
> > > > No IPR declarations have been submitted directly on this I-D.
> > > >
> > > >
> > > > The document contains these normative downward references.
> > > > See RFC 3967 for additional information:
> > > >     rfc5212: Requirements for GMPLS-Based Multi-Region and
> > Multi-Layer
> > > Networks (MRN/MLN) (Informational - IETF stream)
> >
>
>