Re: Uppercase question for RFC2119 words

"Scott O. Bradner" <> Mon, 28 March 2016 13:58 UTC

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Subject: Re: Uppercase question for RFC2119 words
From: "Scott O. Bradner" <>
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Date: Mon, 28 Mar 2016 09:57:58 -0400
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> On Mar 28, 2016, at 9:28 AM, John Leslie <> wrote:
>   Nonetheless, I restate my opinion:
> ] IMHO, the intent (when 2119 was written), was to define new words
> ] using ASCII uppercase, not to redefine English words.  As evidence,
> ] I cite the three uses of lowercase "must", four uses of lowercase
> ] "should", and five uses of lowercase "may", which are a true challenge
> ] to interpret as 2119 keywords.

well, not quite - it was to make more consistent an existing practice

the use of capitalized words in IETF documents predates RFC 2119 by quite a bit - see,
for example, RFC 1023.  The use became codified by RFC 1122, where the definitions in 
RFC 2119 come from.

As an AD I became frustrated by the number of IDs I was reviewing that used upper case words
but did not include any statement of what the reader was to make of the fact that some words were 
capitalized.  I, and the rest of the IESG at the time, were returning the IDs requesting that the 
authors add some explanation.  The explanations that were added were , to say the least, 
inconsistent. After rather many of these I wrote what became RFC 2119 so that we would at
lets have a consistent explanation of the capitalized words that authors could use if they wanted to.  
There was some interaction on the list that resulted in what is now section 6 of RFC 2119 to
provide guidance on when to use the capitalized words

The wishy washy descriptive rather than proscriptive language in the abstract was because I,
the IESG and the community were not of one mind to say that the use of such capitalized
terms should be mandatory - quite a few people felt that the english language was at 
least good enough to convey  the writer’s intent without having to aggrandize specific words.
Thus the abstract basically was saying: if you want to use capitalized words here is a standard
way to say what they mean - as I recall some RFCs even after 2119 was published included
their own definitions for the capitalized terms because the authors thought they had better