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WAI: Strategies, guidelines, resources to make the Web accessible to people with disabilities

Protocols and Formats Working Group (PFWG) Public Page

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Current Work

Technology Review

W3C invites public comment on the Working Drafts in Last Call. The WAI and the Protocols and Formats Working Group invite anyone who perceives an access problem with these drafts to comment. Submit your comments as directed in the individual drafts; the email addresses vary from document to document.

Technical Reports

W3C Working Drafts under development by this group:

Roadmap for Accessible Rich Internet Applications (WAI-ARIA Roadmap)
Describes accessibility of rich Web content using emerging technologies such as AJAX and DHTML. Information about the ARIA Roadmap work follows.
Accessible Rich Internet Applications (WAI-ARIA)
In partial fulfillment of ARIA Roadmap, describes mappings of user interface controls and navigation to accessibility APIs on different platforms and enables languages to add information about the behavior of elements.
WAI-ARIA Primer
Explains the accessibility problems posed by hybrid technologies such as DHTML and AJAX and introduces the technologies to map controls, AJAX live regions, and events to accessibility APIs. Also describes new navigation techniques to mark common Web elements such as menus, primary content, secondary content, banner information and other types of Web structures.
WAI-ARIA Best Practices
Provides recommended approaches to create accessible Web content using WAI-ARIA roles, states, and properties to make widgets, navigation, and behaviors accessible. Also describes considerations that might not be evident to most implementors from the WAI-ARIA specification alone.
Inaccessibility of Visually-Oriented Anti-Robot Tests: Problems and Alternatives
This paper evaluates the accessibility problems with CAPTCHA, a visual verification system popular on many Web sites, and evaluates a number of more-accessible alternatives to the same problems CAPTCHA claims to solve.
Natural Language Usage -- Issues and Strategies for Universal Access to Information
This paper suggests a possible implementation of a language annotation system to clarify meaning in potentially ambiguous terms.
XML Accessibility Guidelines
The discussions for XAG take place on the public wai-xtech list. This specification is developed by the Working Group.

Dynamic Web Content Accessibility Work effort

The working group has a focused effort to fix the accessibility of Rich Internet Applications. The inaccessibility of these applications has often been categorized as "JavaScript Accessibility Problem." These applications make use of script to re-purpose existing markup to create new application widgets not defined by the format. The accessibility of markup languages, such as XHTML and HTML, depends on the coordination of content and presentation. There is an accessibility problem when rich interaction semantics are added outside the markup. When this happens, the markup no longer expresses the information needed to populate accessibility metadata mapped by the browser to platform accessibility APIs. These accessibility APIs inform assistive technologies of essential knowledge about the interactive objects, and allow the assistive technologies to adapt the presentation of information and the acceptance of user input in a way suitable for the individual user.

Similar problems arise in many other circumstances. A common example is when authors using the HTML <table> element for layout. Likewise, it is formally valid to have an SVG document containing only low-level drawing markup even though the scene created contains create complex graphics that imply richer semantics. Solving these problem in a affordable way requires using cross-cutting technologies such as XHTML Modularization and RDF, technologies that can be used for accessibility reform across many renderable markups popular on the Web.

For example, this work is applicable to Asynchronous JavaScript and XML (AJAX).  AJAX is an content compositioni style that lets developers create rich interactive applications like RIAs. AJAX is a key component in these applications, whereby JavaScript makes asynchronous, http requests within your page to exchange data with a web server. Scripted web content processes the data received. This data may be used to update parts of what you see on your web page without reloading the entire page. In addition to performance benefits, this capability allows authors create rich visualizations much as you find in installed GUI applications. Making this accessible requires the use of something like our new dynamic web accessibility specifications to assign the following semantics to the content:

The user agent then maps this information to platform accessibility APIs.

These specifications are designed to also support XHTML markup as rendered in today's desktop browsers. 

The work has been divided into four documents.  The current working drafts of these are:

Roadmap for Accessible Rich Internet Applications (WAI-ARIA Roadmap)
This roadmap that describes the problem, what W3C specifications will be used to correct the problem, and the timeline for the new specifications.
Accessible Rich Internet Applications (WAI-ARIA)
This specification provides an ontology of roles, states, and properties that set out an abstract model for accessible interfaces and can be used to improve the accessibility and interoperability of Web Content and Applications. This information can be mapped to accessibility frameworks that use this information to provide alternative access solutions. Similarly, this information can be used to change the rendering of content dynamically using different style sheet properties. The result is an interoperable method for associating behaviors with document-level markup.
WAI-ARIA Primer
Explains the accessibility problems posed by hybrid technologies such as DHTML and AJAX and introduces the technologies to map controls, AJAX live regions, and events to accessibility APIs. Also describes new navigation techniques to mark common Web elements such as menus, primary content, secondary content, banner information and other types of Web structures.
WAI-ARIA Best Practices
Provides recommended approaches to create accessible Web content using WAI-ARIA roles, states, and properties to make widgets, navigation, and behaviors accessible. Also describes considerations that might not be evident to most implementors from the WAI-ARIA specification alone.
Techniques and examples of how to apply these technologies to create rich internet applications are discussed on the wai-xtech mailing list.  People who want to participate in this discussion should email the PFWG Chair to request subscription.

Publications

The PFWG people (working under the PF or HC WG name) have been responsible in the past for the incorporation of a number of the accessibility improvements introduced into W3C formats from HTML 4.0 onward including CSS, SMIL, SVG and VoiceXML. Some of these are are discussed in the following education notes:

About the PFWG

Contacts:

The PFWG looks at the formal Web technologies (protocols, formats, etc.) from an accessibility perspective. Best practices for using these technologies are addressed by other WAI groups, producing guidelines explaining how to use the technologies.

The principal output of this working group is feedback to other W3C working groups developing specification, on how to ensure that their work can allow for accessibility. This does not generally create deliverables in the form of W3C publications.

In particular, the group tries to review at least every Last Call working draft.

The PFWG also works on the XML Accessibility Guidelines (XAG).

The charter of the working group (extended to 30 June 2008) outlines the goals, work methods, and requirements for participation. Another document explains how to join the group. It also explains why the working drafts and email archives of this group are in the members-only area. This activity is conducted by the W3C as part of its Web Accessibility Initiative

Mailing Lists

Some areas of related work:

Protocols and Formats

On the growing edge of the Web we find Protocols and Formats such as:

Other WAI Groups

Most accessibility issues involve cooperative work between the PFWG and its sister groups within the WAI, particularly

Patent Disclosures

W3C maintains a public list of any patent disclosures made in connection with the deliverables of the group; that page also includes instructions for disclosing a patent.

Al Gilman <Alfred.S.Gilman@IEEE.org> - Chair, PFWG
Michael Cooper <cooper@w3.org> - Staff Contact