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Re: definition of User Agent

From: Loretta Guarino Reid <lguarino@adobe.com>
Date: Thu, 03 Nov 2005 07:34:54 -0800
To: John M Slatin <john_slatin@austin.utexas.edu>, Christophe Strobbe <christophe.strobbe@esat.kuleuven.be>, <w3c-wai-gl@w3.org>
Message-ID: <BF8F6E1E.2B4A%lguarino@adobe.com>

I think we need a clarification somewhere, either in the definition of "user
agent" or the definition of "programmatically determined", that points out
the interaction between these two definitions.

I worry because I see comments from the working group that "of course X can
be programmatically determined, since the user agent is rendering it".
Although the visual rendering portion of the user agent may have the
information, the assistive technology part may not.


On 11/3/05 7:18 AM, "John M Slatin" <john_slatin@austin.utexas.edu> wrote:

> 
> For what it's worth, the Introductory material for the 30 June working draft
> discusses (and tries to clarify) the definition of user agent.  We quote both
> parts of the UAAG definition, then go on to point out that UAAG generally uses
> the first part of the definition while WCAG 2 generally uses the second part.
> Here's the relevant content:
> 
> <blockquote>
> WCAG 2.0 uses the term user agents according to the definition published in
> the Glossary for the W3C's User Agent Accessibility Guidelines (UAAG) 1.0.
> UAAG
> 1.0 defines user agents in two ways.
> List of 2 items
> 1.The software and documentation components that together, conform to the
> requirements of the User Agent Accessibility Guidelines 1.0
> [UAAG10].
> 2.Any software that retrieves and renders Web content for users. This may
> include Web browsers, media players, plug-ins, and other programs - including
> assistive technologies - that help in retrieving and rendering Web content.
> list end
> 
> UAAG 1.0 most often uses the first definition. By contrast, WCAG 2.0 most
> often uses the second definition. It is important to note that assistive
> technologies
> are included in this definition. (Assistive technologies include screen
> readers, screen magnifiers, on screen and alternative keyboards, single
> switches,
> and a wide variety of input and output devices that meet the needs of people
> with disabilities.)
> 
> </blockquote>
> 
> Maybe the explanatory paragraph could be added as a note to the definition as
> it appears in the Gloassary? This way we stay consistent with UAAG while
> highlighting how WCAG differs.
> 
> John
> 
> <blockquote>
> WCAG 2.0 uses the term user agents according to the definition published in
> the Glossary for the W3C's User Agent Accessibility Guidelines (UAAG) 1.0.
> UAAG
> 1.0 defines user agents in two ways.
> List of 2 items
> 1.The software and documentation components that together, conform to the
> requirements of the User Agent Accessibility Guidelines 1.0
> [UAAG10].
> 2.Any software that retrieves and renders Web content for users. This may
> include Web browsers, media players, plug-ins, and other programs - including
> assistive technologies - that help in retrieving and rendering Web content.
> list end
> 
> UAAG 1.0 most often uses the first definition. By contrast, WCAG 2.0 most
> often uses the second definition. It is important to note that assistive
> technologies
> are included in this definition. (Assistive technologies include screen
> readers, screen magnifiers, on screen and alternative keyboards, single
> switches,
> and a wide variety of input and output devices that meet the needs of people
> with disabilities.)
> 
> </blockquote>
> 
> 
> 
> "Good design is accessible design."
> 
> Dr. John M. Slatin, Director
> Accessibility Institute
> University of Texas at Austin
> FAC 248C 
> 1 University Station G9600
> Austin, TX 78712 
> ph 512-495-4288, fax 512-495-4524
> email jslatin@mail.utexas.edu
> Web http://www.utexas.edu/research/accessibility
> 
> 
> 
> -----Original Message-----
> From: w3c-wai-gl-request@w3.org [mailto:w3c-wai-gl-request@w3.org] On Behalf
> Of Christophe Strobbe
> Sent: Thursday, November 03, 2005 7:49 AM
> To: w3c-wai-gl@w3.org
> Subject: Re: definition of User Agent
> 
> 
> 
> Hi,
> 
> At 05:00 30/10/2005, Gregg Vanderheiden wrote:
> <blockquote>
> I just noticed the definition of user agent in our guidelines
> (...)
> 1.      The software and documentation components that together, conform to
> the requirements of the User Agent Accessibility Guidelines 1.0 (UAAG 1.0).
> This is the most common use of the term in this document and is the usage
> in the UAAG checkpoints.
> 
> 2.      Any software that retrieves and renders Web content for users. This
> may include Web browsers, media players, plug-ins, and other programs 
> including assistive technologies  that help in retrieving and rendering
> Web content.
> 
> (...)
> Isn't the second definition the one we mean most?  Not the first? In fact
> isn't the second definition the only thing we mean by the term user
> agent?
> </blockquote>
> 
> In my opinion, we can only use the second definition. We can't safely
> assume that user agents conform to UAAG: for some technologies, the user
> agent is not something that is installed on a device controlled by the
> user. For VoiceXML applications, the user agent is the VoiceXML processor
> [1] or the "VoiceXML interpreter context" [2]. This is software that is
> installed on a machine that a user accesses by telephone. It acts upon
> events caused by user action (e.g. spoken or character input, disconnect,
> ...) and retrieves files from a document server (e.g. a Web server) when
> necessary.
> 
> 
> [1] In VoiceXML 2.0:
> http://www.w3.org/TR/2004/REC-voicexml20-20040316/#dmlAConformanceProcessor -
> in VoiceXML 2.1 CR:
> http://www.w3.org/TR/2005/CR-voicexml21-20050613/#sec-conform-processor
> [2] http://www.w3.org/TR/voicexml20/#dml1.2.1
> 
> Regards,
> 
> Christophe Strobbe
Received on Thursday, 3 November 2005 15:35:13 GMT

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