Last Call Review of draft-ietf-i2rs-yang-network-topo-14
review-ietf-i2rs-yang-network-topo-14-rtgdir-lc-robles-2017-07-24-00

Hello,

I have been selected as the Routing Directorate reviewer for this draft. The
Routing Directorate seeks to review all routing or routing-related drafts as
they pass through IETF last call and IESG review, and sometimes on special
request. The purpose of the review is to provide assistance to the Routing ADs.
For more information about the Routing Directorate, please see
​http://trac.tools.ietf.org/area/rtg/trac/wiki/RtgDir

Although these comments are primarily for the use of the Routing ADs, it would
be helpful if you could consider them along with any other IETF Last Call
comments that you receive, and strive to resolve them through discussion or by
updating the draft.

Document: draft-ietf-i2rs-yang-network-topo-14.txt
Reviewer: Ines Robles
Review Date: 07-25-2017
Intended status: Standards Track

Summary:
I have some minor concerns about this document that I think should be resolved
before publication.

Comments:

I believe the draft is technically good. This document is well written and
clear to understand. The figures are clear and helpful.

Major Issues:

No major issues found.

Minor Issues:

Since this document specifies a data model, I would include some text related
to the Information Model [RFC 3444]. How would it be in this context?

1- Section 1

  1.a following Figure 1 (Page 4):

    I would add in the figure the corresponding section that explain the
    module. e.g. Abstract Network Model, I would add in the figure "Abstract
    (base) Network Model" and "section 4.1". The same for "Abstract Topology
    Model", should it be section 4.2?

  1.b -following Figure 2 (Page 5):

      1.b.1- " X1 and X2 - mapping onto... ",  I think it would be "X1 and X3
      mapping onto..."

      1.b.2- " a single L3 network element", I would add in this case (Y2) "a
      single L3 (Y2) network element", the same for "The figure shows a single
      "L3" network element mapped onto multiple "Optical" network elements.", I
      would add "The figure shows a single "L3" network element (Y2) mapped
      onto multiple "Optical" network elements [Z] and [Z1]."

      1.b.3- I would expand ROADMs --> Reconfigurable Optical Add/Drop
      Multiplexers (ROADMs)

2- Section 2:

  2.1- I would add a reference to RFC 6020, since the document uses terminology
  e.g container, augment, etc. which are defined in 6020. Even if this RFC is
  mentioned in the normative reference, still I would add it here as well.

3- Section 3:

  3.1-  ReST is mentioned here but not in the rest of the draft, is this
  correct?

Nits:

1- Pag. 18: is that correct?: "(a string is a string is a string)"

2- pag. 34: I would expand NMS -> NMS (Network Management System)

3- pag. 34: I would add a definition about TE Topology : "TE-Topology: The TE
Topology is a schematic arrangement of TE nodes
   and TE links in a given TED. It forms the basis for a graph suitable
   for TE path computations."
   [https://tools.ietf.org/html/draft-ietf-teas-yang-te-topo-12]

4- pag. 34: topoogical -> topological

5- pag 35: "uber-network device" -> over-network device?

Thanks,

Ines.