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Document: draft-ietf-ippm-twamp-yang-11
Reviewer: Pete Resnick
Review Date: 2018-06-19
IETF LC End Date: 2018-04-27
IESG Telechat date: 2018-06-21

Summary:

Ready with maybe Issues, but probably just Nits. Not my area of expertise by any means, but the document looks generally solid. Could definitely use a bit of copy editing.

Major issues:

None.

Minor issues:

I don't think there are any issues here. However, some of the things I've got as Nits in the below section could amount to actual issues if I've misunderstood what you meant. The editorial suggestions I give below should be fine if they are nits, but do make sure that I haven't identified a real issue.

Nits/editorial comments: 

3.1 - s/The test session name that MUST be identical/The test session name, which MUST be identical
(Unless you mean something really weird that I don't think you mean. If you don't see the difference, then trust me, you mean "which", not "that".)

4.1 -

OLD
   Specifically, mode-preference-chain lists the
   mode and its corresponding priority, expressed as a 16-bit unsigned
   integer, where zero is the highest priority and subsequent integers
   increase by one.
   
This is a bit confusing. I think you mean:

NEW
   Specifically, mode-preference-chain lists the mode and its
   corresponding priority, expressed as a 16-bit unsigned integer.
   Values for the priority start with zero, the highest priority, and
   subsequent priority value increases by one.

OLD
   In turn, each ctrl-connection holds a list of test-session-request.
   test-session-request holds information associated with the Control-
   Client for this test session.

A bit awkward. I suggest:

NEW
   In turn, each ctrl-connection holds a test-session-request list. Each
   test-session-request holds information associated with the
   Control-Client for this test session.

OLD
   The Control-Client is also responsible for scheduling TWAMP-Test
   sessions so test-session-request holds information related to these
   actions (e.g. pm-index, repeat-interval).

The word "so" in there is weird. Do you mean "therefore", or "such that", or something else? I just had a bit of trouble understanding what you meant.

4.2 - In the penultimate paragraph, change "key-id" to either "The key-id" or "The KeyID".

Please note: I did not thoroughly review the YANG in section 5.2 or the examples in Section 6 or Appendix A. I gave them a quick run through, but did not check for complete consistency with the rest of the text. The below two items are simply things I happened to spot because I was looking at particular pieces of the module.

5.2 -

           leaf priority {
             type uint16;
             description
               "Indicates the Control-Client Mode preference priority
                expressed as a 16-bit unsigned integer, where zero is
                the highest priority and subsequent values
                monotonically increasing.";
           }

I am almost positive that you don't mean "monotonically increasing". I'm guessing you mean "increase by one".

              Depending on the Modes available in the TWAMP Server
              Greeting message (see Fig. 2 of RFC 7717), the
              this Control-Client MUST choose the highest priority
              Mode from the configured mode-preference-chain list.";

Typo: "the this Control-Client"