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Re: Fwd: Three bits on MediaTypes and IANA

From: Mark Baker <distobj@acm.org>
Date: Tue, 15 Jan 2002 01:29:29 -0500 (EST)
Message-Id: <200201150629.BAA22859@markbaker.ca>
To: reagle@w3.org
Cc: www-tag@w3.org
> IANA/ISI directory
> 
> IANA has made progress in maintaining a living directory of assignments on
> the Web at http://www.iana.org/numbers.html . For media types, this
> directory now refers to:
>   http://www.iana.org/assignments/media-types/
> This is an improvement in that I have greater confidence in the
> persistence of this URI over that of the ISI:
>   http://www.isi.edu/in-notes/iana/assignments/media-types/
> However, under iana.org they now only provide a URI for the top level types
> (and we want a URI for every type and a way to encode their parameters.)
> For example:
>   http://www.iana.org/assignments/media-types/text/
> (There's no way to specify text/xml with a URI as one could do under ISI:
>   http://www.isi.edu/in-notes/iana/assignments/media-types/text/xml  )

Hmm, odd, it seems some types get their own URI and others don't.
For example, RTF gets one;

http://www.iana.org/assignments/media-types/text/rtf

A cursory glance of this directory suggests that any media type
registered through an RFC, doesn't get its own media type.
How's that for a disincentive?! 8-)

> Orthogonally, Eastlake has specified a way of mapping media-types and URIs
> amongst each other:
>   http://www.ietf.org/internet-drafts/draft-eastlake-cturi-03.txt
> This draft addresses much of the tricky character encoding and parameter
> issues within a URI but relies on the provision of a new URI scheme
> "Content-Type:" (Additionally, Eastlake provides a URI to Media Type
> mapping which is a neat proof-of-concept but I'm not sure its worth the
> complexity in that spec.)
> 
> Consequently, it'd be best if we could use Eastlake's encoding and
> parameter rules for URIs hosted at iana.org (instead of creating a
> Content-Type URI scheme) where there was a single de-referencable URI for
> every registered media type and its possible parameters.

I'm all for more HTTP URIs, though I don't know that Eastlake's encoding
(or any standardized one) is required.  The relationship between;

  http://www.iana.org/assignments/media-types/text/plain

and

  http://www.iana.org/assignments/media-types/text/plain?charset="foo"

(or whatever URI structure IANA decides to use)

should be made explicit through linking.  See Tim's Opacity "axiom",
which is quickly becoming a favorite of mine;

   http://www.w3.org/DesignIssues/Axioms.html#opaque

MB
-- 
Mark Baker, Chief Science Officer, Planetfred, Inc.
Ottawa, Ontario, CANADA.      mbaker@planetfred.com
http://www.markbaker.ca   http://www.planetfred.com
Received on Tuesday, 15 January 2002 01:28:21 GMT

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