Re: [apps-discuss] "X-" revisited

Dave CROCKER <> Fri, 01 July 2011 03:13 UTC

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Date: Thu, 30 Jun 2011 20:13:40 -0700
From: Dave CROCKER <>
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Subject: Re: [apps-discuss] "X-" revisited
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On 6/30/2011 4:22 AM, Eric Burger wrote:
> The difference between protocol parameters and domain names is domain names are meant for human consumption, while protocol parameters are arbitrary strings of ASCII or UTF-8 text. A protocol might use the string "kritisch" to mean "something critical." Great -- people building user interfaces will read the RFC, know that parameter is "kritisch" and will display "critical," "crucial," "krytyczny," or whatever is appropriate for the user. For that matter, one could really use the string "foobar" to mean "something criticial" or even the number 42. The protocol will work just fine, and users (who do NOT read what is on the wire) can have a great experience.

You have the theory down exactly correctly, IMO.  The practice however matches 
the theory only partially.  Were all fieldnames fully registered, it would 
probably match completely, but they aren't.

In point of fact, most header fields are meant for human consumption and that 
includes their fieldnames, which frequently are entirely ad hoc and can't be 
predictably translated.

> The point is *this* name space is huge and fungible, whereas the DNS is large and NOT fungible.

I guess I'm missing what the import is, for the distinction(s) you are making.


   Dave Crocker
   Brandenburg InternetWorking