At its most basic level, RDF, an initiative of the World Wide Web Consortium (W3C), is a framework for metadata. In RDF, the basic model is composed of resources, properties and statements. Anything described under the RDF model is called a resource. A National Report from Mexico posted on the CBD website, for example, is a resource. Properties are characteristics, attributes or relations used to describe a resource. A statement defines a resource with a named property and the value of that property. In a statement, these categories are usually referred to as the subject (resource), the predicate (property) and the object (literal).

In other words, the above model offers a structure to assist with interoperability between applications for the exchange of web-based machine readable information. RDF, therefore, when used with appropriated information exchange protocols such as SOAP (Simple Object Access Protocol) and syntax encoding languages such as XML, provides a simple and effective solution to facilitate interoperability between systems based on distributed metadata registration models.

Note also that RDF and XML are complementary--RDF can specify semantics for XML data in a standardized, interoperable manner. Furthermore, because the Dublin Core can be accomodated within the RDF model, RDF offers the Clearing-House Mechanism a standardized model for representing named properties and values. In other words, RDF uses XML as its interchange syntax. Moreover, the Dublin Core can be represented in many different syntax formats allowing it to be easily encoded in XML using basic RDF. This is ideal for the type of data registered on the Convention web site; RDF can offer the Clearing-House Mechanism the means to evaluate equivalence in meaning, thereby greatly simplyfying the exchange of information among distributed information systems.

In summary, RDF offers the Clearing-House Mechanism:

· a model to facilitate interoperability of machine readable information/metadata;
· a framework for supporting information or resource description and cataloguing, i.e., metadata;
· better tools to facilitate resource discovery and indexing.

More information on RDF can be found on the W3C web site: http://www.w3c.org