The group discussed the concept of 'a POWDER Processor' and agreed that such a thing needs to be defined. As a minimum a POWDER processor will handle two functions:
For a given URI u, the function describe(u) will return RDF/XML that has u as the subject.
For a given description, d, the function resourcesWith(d) will return one or more regular expressions, all of which must match for a resource to be described by d.
There are many options that can be added to this - describe using a given dataset, only use DRs from particular creators etc, returning DRs relevant to the query and so on. Many of these options will be documented but only the two core functions will be mandatory.
The group then turned to discussion of the work done recently by Stasinos Konstantopoulos
. Subject to consultation outside the group, this work will become a separate new document called POWDER: Formal Semantics. This will underpin the semantics of POWDER-S which in turn will underpin the 'native' POWDER. This creates a 3 layered approach, however, the 3 layers all build on each other. Only POWDER and POWDER-S need be implemented, but the formal semantics, although largely theoretical, provide a benchmark against which the other two can be tested. Since a lot of work has been done in this area already, it will not add significantly to the group's workload.
Finally, subject to final confirmation, the next face to face meeting will be on Monday 14th - Tuesday 15th July in London.