Re: SHOULD vs MUST

Iljitsch van Beijnum <iljitsch@muada.com> Fri, 27 June 2008 13:49 UTC

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From: Iljitsch van Beijnum <iljitsch@muada.com>
To: Dave Cridland <dave@cridland.net>
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Subject: Re: SHOULD vs MUST
Date: Fri, 27 Jun 2008 15:48:53 +0200
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On 25 jun 2008, at 9:58, Dave Cridland wrote:

> I think we should be biting the bullet and doing so, however -  
> otherwise we risk having the old behaviour used in new  
> implementations more than it would be otherwise. The primary reason  
> for doing the behaviour you describe is a kind of political  
> correctness, and introduces a political-SHOULD I'm not sure I care  
> for.

This shows that it's very important to avoid the situation where there  
exist implementations of insufficiently mature specifications: once  
those implementations are out there, the protocols must virtually  
forever support them.

This is of course not compatible with "let's ship a 80% workable spec  
and hammer out what's missing in the next version" thinking that is  
not uncommon in the IETF.

-- 
The trouble with doing something right the first time is that nobody  
appreciates how difficult it was. - Walt West

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