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Team Comment on "SA-REST: Semantic Annotation of Web Resources" Submission

W3C is pleased to receive the SA-REST: Semantic Annotation of Web Resources Submission from Wright State University.

The Submission proposes poshformat for identifying the meaning and purpose of regions of HTML documents. Specifically, it proposed markup for three concepts:

domain-rel
identifies the "domain information" for a document or region (e.g. <div/>) in a document.
sem-class
identifies the meaning or purpose of a non-block element (e.g. <img>).
sem-rel
describes a link in the marked-up document."captures the semantics of a link".

The "REST" in SA-REST stems from the initial use case which is the markup of RESTful Web Services. In this reqard, SA-REST provides an alternative to WADL and SAWSDL. (SAWSDL annotations can be added to WSDL bindings of type http://www.w3.org/ns/wsdl/http to label the semantic of RESTful Web Services.) SA-REST is motivated by other use cases, such as improving search accuracy.

Unlike other microformats, SA-REST suggests the labeling semantics with URLs in title attributes; these URLs would be visible in browsers which display element titles. The intention of the title attribute is to contain human understandable information (although, unfortunately, the relevant part of the HTML specification does indeed fail to make this absolutely clear). Using this attribute to help developers instead of catering for the end-user of a page raises serious accessibility issues that are not addressed by the submission. Note that the microformat community has introduced the "value-class" pattern to avoid such accessibility problems.

Section 4 of the Submission proposes using GRDDL to extract RDF assertions from documents marked up with SA-REST attributes. A normative XSLT would specify the representation of SA-REST in RDF.

It is also unclear how the semantics in a sem-rel annotation (e.g. <a class="sem-rel" title="http://example.org/#firstname">...</a>) differ from those of a rel attribute (<a rel="http://example.org/#firstname">...</a>). Using rel would mean making RDFa, although the vocabulary would have to be carefully checked against the way RDFa operates.

Next Steps

As of today, W3C has no plans to take up recommendation-track work based on this Member Submission.

Next Steps

We encourage people interested by existing work around description of services to discuss on the public-web-http-desc@w3.org

$Date: 2010/05/20 16:52:45 $