- From: Jason White <jasonw@ariel.ucs.unimelb.edu.au>
- Date: Sun, 26 Aug 2001 18:40:08 +1000
- To: w3c-wai-gl@w3.org
Since several participants in this working group have expressed support for the kind of conformance scheme that I suggested last week, I shall here provide a more concrete, and indeed simpler, version. Disclaimer: I am not necessarily advocating this as a solution. Instead, I am trying to transform various suggestions which have been raised on this mailing list, into a specific proposal, the merits of which can then be debated more easily. General structure of the conformance scheme: Three conformance classes are proposed. A conformance claim can be made in respect of one, two or all three conformance classes, and must include: a. Identification of the web content (page, site, etc.) to which it pertains. b. The version of the guidelines to which conformance is claimed. c. The date on which the conformance claim was made. Any method of expressing a conformance claim is acceptable so long as it includes all of the needed information and can be accessed (with or without suitable software tools, e.g., RDF processing applications) by users of the web site and/or search tools. To facilitate the making of conformance claims, the working group provides: 1. An RDF schema (defined in cooperation with ER WG). 2. An icon and associated text equivalent, which can serve as a link to a page that provides details of the conformance claim. Note: if it is possible to combine the RDF with an XHTML page specifying the conformance claim, so that both machine-readable and human-readable versions are given, an example of this should be provided. Next come the definitions of the conformance classes. For each conformance class, the conformance claim must name the class and list the checkpoints which are claimed to have been met. This list must include all "essential" checkpoints in the particular class (see below); otherwise the conformance claim is invalid (this can be checked automatically). The checkpoints in each class are divided into two categories, "essential" and "recommended". These take the place of the WCAG 1.0 priority scheme. A checkpoint within a particular class is essential if failure to satisfy it will render the content inaccessible to identifiable groups of users whose needs are addressed by the checkpoint. Conformance class 1, Device and modality independence: Essential: checkpoints 1.1, 1.2, 1.5 and 4.1. Recommended: checkpoints 1.3, 1.4, 4.2, 4.3 and 4.4. Conformance class 2, Interaction and navigation: Essential: Checkpoints 2.3, 2.4, 2.5, 2.6 and 2.7. Recommended: checkpoints 2.1 and 2.2. Note: this is where it starts to break down; any checkpoint under guideline 2, if not satisfied, will arguably make the content inaccessible to somebody. Conformance class 3, Comprehension: Essential: checkpoints 3.3, 3.4 and 3.5. Recommended: checkpoints 3.1 and 3.2. Note: the same qualification applies as in the case of guideline 2. Also, there is bound to be a debate concerning whether checkpoint 3.3 should be in the "essential" or "recommended" category (it is time to put on the flame-resistant attire). If some such conformance system were adopted, then I would recommend, by default or as an optional view, ordering the checkpoints under each guideline by listing the "essential" checkpoints first, followed by the "recommended" checkpoints. It would also be helpful to choose better terms than "essential" and "recommended" (the latter in particular may be confusing, given that the entire document is referred to as a W3C Recommendation; but "optional", or "inessential" or even "suggested" give the wrong impression. Recommended checkpoints are just that--very important but not so indispensable that failure to satisfy them renders the content absolutely inaccessible to identifiable groups). Here is a non-exhaustive list of variations on the above proposal: 1. Combine interaction/navigation and comprehension into a single class, thereby defining two conformance classes. 2. Drop the distinction between "essential" and "inessential", either completely, or in such a way as to retain it in the "device and modality-independence" class, where the issues seem to be more clear-cut. In the latter case, the notion of "essential/recommended" would be dropped and one would simply define the "device and modality independence" class as: All checkpoints in guidelines 1 and 4, but must include checkpoints 1.1, 1.2, 1.5 and 4.1. 3. Drop the "conformance classes" as defined above, and simply require that a conformance claim list the checkpoints which have been met. This version of the conformance scheme could be implemented with or without the notion of "essential checkpoints" (see proposal 2, above).
Received on Sunday, 26 August 2001 04:40:19 UTC