Re: [Dots] Alissa Cooper's Discuss on draft-ietf-dots-signal-channel-31: (with DISCUSS and COMMENT)

[<[e-mail]>]

Hi Ben, 

I already went with the s/by default, .... MUST/SHOULD to address the comment from Alissa. I also implemented the other change proposals. 

FWIW, the updated version is available at: https://github.com/boucadair/draft-ietf-dots-signal-channel/blob/master/draft-ietf-dots-signal-channel-31.txt.

Cheers,
Med

> -----Message d'origine-----
> De : Benjamin Kaduk [mailto:[e-mail]]
> Envoyé : lundi 6 mai 2019 18:02
> À : Konda, Tirumaleswar Reddy
> Cc : Alissa Cooper; BOUCADAIR Mohamed TGI/OLN; draft-ietf-dots-signal-
> [e-mail]; Liang Xia; [e-mail]; [e-mail]; IESG
> Objet : Re: [Dots] Alissa Cooper's Discuss on draft-ietf-dots-signal-channel-
> 31: (with DISCUSS and COMMENT)
> 
> On Fri, May 03, 2019 at 07:17:55AM +0000, Konda, Tirumaleswar Reddy wrote:
> > Hi Alissa,
> >
> > Please see inline
> >
> > From: Dots <[e-mail]> On Behalf Of Alissa Cooper
> > Sent: Thursday, May 2, 2019 8:50 PM
> > To: [e-mail]
> > Cc: [e-mail]; Liang Xia
> <[e-mail]>; [e-mail]; IESG <[e-mail]>; dots-
> [e-mail]
> > Subject: Re: [Dots] Alissa Cooper's Discuss on draft-ietf-dots-signal-
> channel-31: (with DISCUSS and COMMENT)
> >
> >
> > CAUTION: External email. Do not click links or open attachments unless you
> recognize the sender and know the content is safe.
> >
> >
> > ________________________________
> > Hi Med,
> >
> >
> > On May 2, 2019, at 3:18 AM,
> [e-mail]<mailto:[e-mail]> wrote:
> >
> > Hi Alissa,
> >
> > Please see inline.
> >
> > Cheers,
> > Med
> >
> >
> > -----Message d'origine-----
> > De : Alissa Cooper via Datatracker [mailto:[e-mail]]
> > Envoyé : jeudi 2 mai 2019 03:56
> > À : The IESG
> > Cc : [e-mail]<mailto:draft-ietf-dots-signal-
> [e-mail]>; Liang Xia; dots-
> > [e-mail]<mailto:[e-mail]>;
> [e-mail]<mailto:[e-mail]>;
> [e-mail]<mailto:[e-mail]>
> > Objet : Alissa Cooper's Discuss on draft-ietf-dots-signal-channel-31: (with
> > DISCUSS and COMMENT)
> >
> > Alissa Cooper has entered the following ballot position for
> > draft-ietf-dots-signal-channel-31: Discuss
> >
> > When responding, please keep the subject line intact and reply to all
> > email addresses included in the To and CC lines. (Feel free to cut this
> > introductory paragraph, however.)
> >
> >
> > Please refer to https://www.ietf.org/iesg/statement/discuss-criteria.html
> > for more information about IESG DISCUSS and COMMENT positions.
> >
> >
> > The document, along with other ballot positions, can be found here:
> > https://datatracker.ietf.org/doc/draft-ietf-dots-signal-channel/
> >
> >
> >
> > ----------------------------------------------------------------------
> > DISCUSS:
> > ----------------------------------------------------------------------
> >
> > = Section 3 =
> >
> > "By default, a DOTS signal channel MUST run over port number TBD as
> >   defined in Section 9.1, for both UDP and TCP, unless the DOTS server
> >   has a mutual agreement with its DOTS clients to use a different port
> >   number.  DOTS clients MAY alternatively support means to dynamically
> >   discover the ports used by their DOTS servers (e.g.,
> >   [I-D.boucadair-dots-server-discovery])."
> >
> > MUST implies an absolute requirement, so "MUST .... unless" is a
> problematic
> > construction.
> >
> > [Med] It seems that you missed "By default, “.
> >
> > Even with “by default” this still is problematic. MUST indicates an
> absolute requirement.
> >
> > [TR] “MUST (NOT)..unless” construction is used in several specifications,
> please see https://tools.ietf.org/html/rfc8094#section-3.1 and
> https://tools.ietf.org/html/rfc7232#section-2.2.1
> 
> Alissa is correct that MUST is absolute within the realm that it applies
> to, so we need to be clear about what domain the requirement applies to.
> The text in the -31 here is particularly problematic because of the
> following "MAY alternatively" which is in a different sentence and has a
> confusing relationship to the previous text.  A (hopefully clearer)
> proposal:
> 
> In some cases, a DOTS client and server may have mutual agreement to use a
> specific port number, such as by explicit configuration or dynamic
> discovery [I-D.boucadair-dots-server-discvory].  Absent such mutual
> agreement, the DOTS signal channel MUST run over port number TBD as defined
> in Section 9.1, for both UDP and TCP.
> 
> -Ben