[Gen-art] GenART post-telechat comment on draft-ietf-tram-turn-mobility-08

[Pete Resnick <[e-mail]>]

Greetings,

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Document: draft-ietf-tram-turn-mobility-03
Reviewer: Pete Resnick
Review Date: 2016-09-06
IESG Telechat date: 2016-09-01

Summary: This is an odd post-telechat review, but I think the draft has 
gone from "Ready" to "Ready with an issue" because of an IESG Eval 
change.

Details:

I did not get to my post-Last Call GenART review of 
draft-ietf-tram-turn-mobility until after the telechat. Had I done so, 
which would have been on version -05, I would have said "Looks fine to 
me". However, I happened to look at the latest version, figuring I would 
just confirm. I found that a change was made in response to an IESG 
Evaluation comment from Suresh 
<https://mailarchive.ietf.org/arch/msg/tram/SYVAXc1dF6xUcm0OQ9xyuaknJco>:

> ----------------------------------------------------------------------
> COMMENT:
> ----------------------------------------------------------------------
>
> * Section 3.2.1
>
> The section on sending a Refresh when the IP address does not change
> needs a little bit more tightening. Given that the server would reject
> the request with a mobility ticket in this case, it would be good to 
> put
> in an explicit restriction to not add the mobility ticket in the
> following statement
>
> OLD: If a client wants to refresh an existing allocation and update 
> its
> time-to-expiry or delete an existing allocation, it will send a 
> Refresh
> Request as described in Section 7.1 of [RFC5766]
>
> NEW:
> If a client wants to refresh an existing allocation and update its
> time-to-expiry or delete an existing allocation, it MUST send a 
> Refresh
> Request as described in Section 7.1 of [RFC5766] and MUST NOT include 
> a
> MOBILITY-TICKET attribute.

I'm not sure if the "MUST NOT" in the latter part of the sentence is 
correct: Since the server will reject it anyway, I don't see the harm in 
including the attribute that the "MUST NOT" implies, but perhaps this is 
belt-and-braces protocol description. On this point, I can't complain 
too much. However, I believe Suresh was incorrect in suggesting the 
first "MUST", and it should be removed. There is no harm being prevented 
here. "If a client wants X, it MUST send Y" is absolutely no different 
protocol-wise from "If a client wants X, it will send Y". The "MUST" is 
a misuse. I believe that this change should be undone before 
publication.

pr
-- 
Pete Resnick <http://www.qualcomm.com/~presnick/>
Qualcomm Technologies, Inc. - [phone]