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Why an standalone image shall conform to WCAG 2.0? (was Re: BIG ISSUE -- re Delivery Units)

From: Carlos A Velasco <Carlos.Velasco@fit.fraunhofer.de>
Date: Mon, 13 Feb 2006 09:19:18 +0100
Message-ID: <43F04106.70806@fit.fraunhofer.de>
To: Gregg Vanderheiden <gv@trace.wisc.edu>
Cc: w3c-wai-gl@w3.org

Hi Gregg,

You keep ignoring the critical question I raised in my first email to 
this thread. Here is my last try. In [1] it is said:

<quote>
Conformance Notes

A delivery unit conforms to WCAG 2.0 at a given conformance level only 
if all content provided by that delivery unit conforms at that level.
</quote>

That is senseless. Many DUs contain media elements that are made 
accessible through the whole set of elements in the main DU, or via 
linked information (e.g., longdesc). Cumbersome example: I can have in 
two different iframes (or frames) a non-accessible PDF document and an 
accessible HTML version of the same document. I think the page is 
accessible, isn't it (ignore frame accessibility for the sake of the 
argument)? Thus the issues does not lie on DUs, but on this paragraph.

Into other issues, the document follows ...

<quote>
Note: If multiple representations can be retrieved from a URI through 
content negotiation, then the conformance claim would be for the 
delivery unit that is returned when no negotiation is conducted (unless 
the server returns an error for that condition, in which case one of the 
negotiated forms must comply).
</quote>

I believe this is an over-simplification of [2]. This paragraph also 
eliminates conformance claims linked to content-negotiation. For 
example, what if I claim the German version of my site (available via 
language negotiation) is accessible, but the english (default) is not?

regards,
carlos

[1] http://www.w3.org/TR/WCAG20/complete.html#N102E1
[2] http://www.w3.org/Protocols/rfc2616/rfc2616-sec12.html#sec12

Gregg Vanderheiden wrote:
>>> So we need to find a way to fix them or delete 8 or so of our core 
>>> success criterion.
> 
>> Which ones?
> 
> All of the ones that have delivery unit in them.
> 


-- 
Dr Carlos A Velasco - http://access.fit.fraunhofer.de/
Fraunhofer-Institut für Angewandte Informationstechnik FIT
   [Fraunhofer Institute for Applied Information Technology (FIT)]
   Barrierefreie Informations- und Kommunikationstechnologie für Alle
   Schloss Birlinghoven, D53757 Sankt Augustin (Germany)
   Tel: +49-2241-142609 Fax: +49-2241-1442609
Received on Monday, 13 February 2006 08:19:55 GMT

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