Re: SHOULD vs MUST case sensitivity

Dave Crocker <> Mon, 30 June 2008 00:31 UTC

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Date: Sun, 29 Jun 2008 17:31:34 -0700
From: Dave Crocker <>
Organization: Brandenburg InternetWorking
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Subject: Re: SHOULD vs MUST case sensitivity
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Randy Presuhn wrote:
>> In what universe does that make sense?
> ...
> One in which when the photocopier's paper jam light goes, the operator SHOULD
>  open the cover and remove any crumpled pieces of paper, which should resolve
>  the problem.
> These are very distinct senses of the word

Wow. I was not aware that the photocopier manual conformed to RFC 2119.

The most distinctive characteristic of the postings arguing in favor of imposing
case sensitivity in documents asserting RFC 2119 semantics is their spontaneous
invocation of relativity.

2119 specifies the meaning of these words... but not relative to whatever other,
particular interpretation that the posters wants to have held as higher
precedence.  And certainly not relative to the long-term reality that English
usage of case has no import on semantics.

Let's be clear.  No matter its own marginal choices for wording, the document's

> In many standards track documents several words are used to signify the 
> requirements in the specification. These words are often capitalized. This 
> document defines these words as they should be interpreted in IETF documents.
>  Authors who follow these guidelines should incorporate this phrase near the 
> beginning of their document:

states that the words be used as defined.  Not as defined -- except according to
the whim of whoever is imposing additional meaning.

English is not case sensitive.  RFC 2119 does not specify case sensitivity.

Assertion that case sensitivity is relevant is, therefore, a matter of personal
whim.  On the average one SHOULD NOT use personal whim as a basis for
interpreting a technical specifications.



   Dave Crocker
   Brandenburg InternetWorking
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