RE: New Version Notification for draft-leiba-rfc2119-update-00.txt

"Dearlove, Christopher (UK)" <> Thu, 11 August 2016 11:27 UTC

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From: "Dearlove, Christopher (UK)" <>
To: Barry Leiba <>, IETF discussion list <>
Subject: RE: New Version Notification for draft-leiba-rfc2119-update-00.txt
Thread-Topic: New Version Notification for draft-leiba-rfc2119-update-00.txt
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Date: Thu, 11 Aug 2016 11:27:52 +0000
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Grammatically, RECOMMENDED is sometimes useful, as using SHOULD instead can produce less clear sentences. In principal the same applies to OPTIONAL, but I've never had cause to use it.

I wouldn't miss SHALL. Except that SHALL is often the word used outside the IETF rather than must, and there may be many RFCs using it, so do need to keep the explanation, even if deprecated to use it in new documents.

Christopher Dearlove
Senior Principal Engineer
BAE Systems Applied Intelligence Laboratories

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-----Original Message-----
From: ietf [] On Behalf Of Barry Leiba
Sent: 09 August 2016 21:09
To: IETF discussion list
Subject: Re: New Version Notification for draft-leiba-rfc2119-update-00.txt

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This draft should be self-explanatory -- and please be sure to look at Section 1.1 for some explanations that may short-cut some of the discussion.

The bottom line is to update BCP 14 (RFC 2119) to
(1) make it clear that the key words MUST(/NOT), SHOULD(/NOT), and MAY are only key words when they're in ALL CAPS, and
(2) deprecate the use of the variants (SHALL, RECOMMENDED, OPTIONAL) so as to avoid reserving an unnecessarily number of key words.

Discussion here, please, before Ben, who has kindly agreed to AD-sponsor this, sends it out for last call.  And we do expect there to be some significant discussion on this one.


On Tue, Aug 9, 2016 at 2:55 PM,  <> wrote:
> A new version of I-D, draft-leiba-rfc2119-update-00.txt has been 
> successfully submitted by Barry Leiba and posted to the IETF 
> repository.
> Name:           draft-leiba-rfc2119-update
> Revision:       00
> Title:          Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words
> Document date:  2016-08-09
> Group:          Individual Submission
> Pages:          4
> URL:  
> Status:
> Htmlized:
> Abstract:
>    RFC 2119 specifies common key words that may be used in protocol
>    specifications.  This document aims to reduce the ambiguity by
>    clarifying that only UPPERCASE usage of the key words have the
>    defined special meanings, and by deprecating some versions of the key
>    words.

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