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From: Jim Allan <jimallan@tsbvi.edu>
Date: Thu, 31 Jan 2013 11:52:17 -0600
Message-ID: <CA+=z1W=kpRzGze0p3R-30ZSm1m455S+HG+r-j8L7u-egtKYWuw@mail.gmail.com>
To: WAI-ua <w3c-wai-ua@w3.org>
Just before the meeting.
below is my current musings trying to make sense of our conformance.
I start with the Definition of UA, That is followed by our expansion of the
definition found in the Implementation document.
I added some examples and conformance claims. I could not think of any for
the web-based.

This is what was done in UAAG10
Huge and complex.

Definition of User Agent

A user agent is any software that retrieves, renders and facilitates
end-user interaction with Web content.

*What qualifies as a User Agent?*

These guidelines employ the following tests to determine if software
qualifies as a user agent. UAAG 2.0 divides potential user agents into

   - platform-based application
   - extension or plug-in
   - web-based application


 If the following three conditions are met, then it is a platform-based

   1. It is a standalone application, and
   2. It interprets any W3C-specified language, and
   3. It provides a user interface or interprets a procedural or
   declarative language that may be used to provide a user interface

This includes desktops, and mobile devices.

Full UAAG 2.0 Conformance

A user agent conforms to UAAG20 at A, AA or AAA level when it meets the all
of the SCs appropriate for the level of conformance. The UA may meet the
appropriate SCs wholly on its own or must list extensions necessary to meet
specified SCs that the UA cannot meet alone.

Partial UAAG 2.0 Conformance - Platform Limitations (Level A, AA, or AAA)

This conformance option may be selected when a user agent is unable to meet
one or more success criteria because of intrinsic limitations of the
platform. The conformance should explain what platform features are missing.


         if a requirement refers to color, but the device only has a
monochrome screen

         if a requirement refers to a keyboard interface, but the device
OS lacks a keyboard interface

         f a requirement refers to a platform accessibility service, but
the device lacks a platform accessibility service

Partial UAAG 2.0 Conformance.

User-Agent A only conforms to the following Success Criteria:

         all met SC are listed.

We do not conform to the following SC  and the reasons are listed


If the following two conditions are met then it is an extension or plug-in:

   1. It is launched by, or extends the functionality of a platform-based
   application, and
   2. Post-launch user interaction is included in, or is within the bounds
   of the platform-based application

This includes most extensions and plugins. It excludes AT, as they are
standalone applications separate from the browser (rule 2 above). It
excludes web-based application plugins (see the definition below).

Conformance for an extension or plugin can be claimed for specific SCs and
the SCs related to configuration behavior.

UAAG 2.0 Conformance for Extension:

A "mouseless browsing" extension allows the following listed browsers (UA1,
UA2) to meet UAAG success criterion 2.3.3 ("Direct activation of Enabled
Elements: The user can move directly to and activate any enabled element in
rendered content."). Additionally we meet these SCs related to user
interface components (Guideline 2.1 2.3.4(?? AA), 2.7.1, 2.7.1, 2.8.1,
3.3.1, 3.3.2)


If the following three conditions are met then it is an web-based

   1. The user interface is generated by a procedural or declarative
   language; and
   2. The user interface is embedded in an application that renders web
   content, and
   3. User interaction is controlled by a procedural or declarative
   language, or if user interaction does not modify the Document Object Model
   of its containing document.

This includes plugins (e.g. media player in object element

UAAG 2.0 Conformance for Web-based User Agent

Jim Allan, Accessibility Coordinator & Webmaster
Texas School for the Blind and Visually Impaired
1100 W. 45th St., Austin, Texas 78756
voice 512.206.9315    fax: 512.206.9264  http://www.tsbvi.edu/
"We shape our tools and thereafter our tools shape us." McLuhan, 1964
Received on Thursday, 31 January 2013 17:52:45 UTC

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