The POWDER Working Group has had three key meetings in the last 9 days.
A quick reminder – POWDER is designing a lightweight system that will enable RDF triples to be applied to groups of resources, typically all those available from a given Web site. Critically, the data will be open to authentication so that when Organization A says that Web site B has properties C, D and E, a machine will be able to seek authentication from Organization A that they really did say that. Think of it as the automated/Semantic Web version of ‘Click to Verify’ when you see a trustmark on a Web site.
On the first of these meetings we also agreed on a coordination step with the Web Application Formats Working Group relating to their Enabling Read Access document. We also made significant progress towards defining the details of the structure of a Description Resource (a more detailed summary of this meeting is also available).
We also had a public event, jointly sponsored by CTIA. This “Stakeholder Meeting” presented several use cases and discussed the potential—and potential problems—of the new protocol. A full report is available.
Finally, a meeting was held with the Mobile Web Best Practices Working Group to discuss mobileOK. This is a key use case for POWDER as it encodes a claim that a group of resources are conformant with Mobile Web Best Practice.
As a result of all these meetings, it’s possible to present a sample Description Resource. One or two minor details have yet to be finalized but this is a good snapshot.
1 <wdr:DR> 2 <foaf:hasMaker rdf:resource="http://www.example.com/foaf.rdf#me" /> 3 <dcterms:issued>2007-07-17</dcterms:issued> 4 <wdr:validFrom>2007-07-21</wdr:validFrom> 5 <wdr:validUntil>2008-05-21</wdr:validUntil> 6 <wdr:hasScope> 7 <wdr:ResourceSet> 8 <wdr:includeHosts>example.org</wdr:includeHosts> 9 </wdr:ResourceSet> 10 </wdr:hasScope> 11 <wdr:hasDescriptors rdf:resource="http://www.w3.org/2007/07/mobileOK#Basic" /> 12 <dc:description>example.org conforms to the mobileOK Basic standard, meaning that basic steps have been taken to provide a functional user experience for users of basic mobile devices</dc:description> 13 <foaf:depiction rdf:resource="http://www.w3.org/ICONS/mobileOKPro.png" /> 14 </wdr:DR>
The namespace declarations are omitted for clarity but
wdr is an abbreviation represents the POWDER namespace (it’s an abbreviation of Web Description Resources).
Some elements are mandatory:
- Attribution (
- Scope (
wdr:hasScopeand the Resource Set it points to)
- The actual descriptors that can be applied to any Resource that matches the Resource Set definition (
wdr:hasDescriptorswhich has a range of a Class called ‘Descriptors’)
All other elements are optional, however, an issue date and a valid until date SHOULD be there.
The most tricky and contentious aspect of all this is likely to be the Resource Set definition. As noted in a blog last week, the relevant document is now a first public working draft. The ambitious target is to get a working draft of the Description Resources document into the public domain around the end of the month.