Last Call Review of draft-ietf-pce-lsp-setup-type-07
review-ietf-pce-lsp-setup-type-07-rtgdir-lc-ceccarelli-2018-01-10-00

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-pce-lsp-setup-type-07

Reviewer: Daniele Ceccarelli

Review Date: 2018-01-10

IETF LC End Date: date-if-known

Intended Status: Standards Track

Summary:

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

Comments:

The draft is a bit confusing on some aspects. I had to read it again a couple
of times to understand that 2 TLVs are defined (probably my fault). If you
could make it clearer in the intro that 2 TLVs are defined each of which with a
precise scope, that would make things easier.

Also the list of the PSTs is a bit confusing. Since each PST is a byte field
why don’t you adopt and encoding like the one used in RFC7138 section 4.1.1.
for the muxing stages? You could encode the PST values like the Stage#1…Stage#
below.

   0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Type = 1 (Unres-fix)   |             Length            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  Signal Type  | Num of stages |T|S| TSG | Res |    Priority   |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    Stage#1    |      ...      |   Stage#N     |    Padding    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  Unreserved ODUj at Prio 0    |             .....             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  Unreserved ODUj at Prio 7    |     Unreserved Padding        |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                   Figure 3: Bandwidth Sub-TLV -- Type 1

Major Issues:

No major issues found.

Minor Issues:

  *   Section 3: definition of the Length field is missing. Further reading the
  document I found it later in section 3. Ordering the definitions of the
  fields accordingly with the order they appear in the TLV improves the
  readability. *   Section 3: why is the PST length needed? Why is not enough
  to use the Length field of the PSTCapability TLV? *   Section 3: “This
  document defines the following PST value:

          o  PST = 0: Path is setup using the RSVP-TE signaling protocol.”
          …please see general comment above.

Nits:

  *   Abstract: I’d suggest substituting “Traffic Engineering paths (TE paths)”
  with Traffic Engineering (TE) paths. *   Requirement language: usually this
  section is a subsection in the body of the draft, not in the abstract. It
  could be put as 1.1? *   Section1: “by sending the ERO and characteristics of
  the LSP”…shouldn’t a “THE” be used between “and” and “characteristics”?

Thanks

Daniele