Meaning and scope of "authored unit"

To start addressing some of the issues raised at last week's meeting:

<propose>
An "authored unit" includes a resource identified by a URI, together
with any other resources directly or indirectly associated with it,
that may be retrieved in the course of rendering or otherwise
processing it.
</propose>

Alternative proposal:

<propose>
An "authored unit" includes a resource identified by a URI, together
with any other resource contained within it.

A resource is contained in an authored unit if it is retreived as part
of it, or linked to it directly or indirectly by a standard linking
mechanism and may be retrieved in the course of rendering or otherwise
processing the authored unit.
</propose>

Remarks

1. The purpose here is to specify that subsidiary resources which may
   be retrieved by a user agent or other processing software, are part
   of (or contained in) the authored unit. This avoids such scenarios
   as where an XHTML document is an authored unit but its associated
  raster-based images, style sheets etc., are not, with the result
   that the conformance claim would only cover the XHTML document
   itself, considered separately from the images and style sheets
   etc., that would be retrieved in the process of rendering it.

2. According to RFC 2396, the fragment identifier is not part of a
   URI, but the query part is. This answers a question raised at last
   week's meeting. In general, I don't think it is a good idea to
   impose restrictions on URI's in order to try to prevent conformance
   claims from being made with respect to, for example, part of a
   document; any such restriction can easily be circumvented.

3. A resource, according to RFC 2396, can be anything with identity.
   This means that the content of a resource (ie., what is obtained
   via a retrieval operation) can change over time, can be constructed
   dynamically and can vary according to any content negotiation which
   is performed.

I propose that where a resource identified by a URI can be retrieved
in multiple forms depending on content negotiation or other aspects of
the delivery context, the resource conforms to WCAG if at least one
version of its content conforms. Where there is a default version that
will be retrieved in the absence of content negotiation, this default
version must conform to WCAG.

Received on Sunday, 25 July 2004 06:25:23 UTC