Concept of metadata interoperability
The actions embodied by metadata interoperability are best explained in the article, Combining RDF and XML Schemas to Enhance Interoperability Between Metadata Application Profiles. These actions include the ability to:
This means that collections which support interoperable metadata protocols allow remote clients to search and retrieve their metadata records. These remote clients can then provide their users with search results from another source, such as DLESE.
Forms of metadata interoperability
The actions described above lead to two forms of metadata interoperability:
Federation requires more effort from data providers but is easier for service providers (i.e., service providers do not need to parse and interpert metadata records). It has, however, scalability issues (i.e., it rapidly becomes unreasonable to distribute a query to more than a few sources). Discovery facilitated through harvesting requires less effort from data providers, but is more difficult for service providers (i.e., the service providers are delivered full metadata records; they then must do something with them for these records to be discoverable in their systems).
Metadata requirements for metadata interoperability
No matter which form of metadata interoperability is pursued, the following information about a metadata framework is required:
Remember that metadata is information about objects (i.e. title, description, author) while data refers to the digital objects and their representations.
DLESE's approach to metadata interoperability
DLESE is using the Open Archive Initiative-Protocol for Metadata Harvesting (OAI-PMH) to provide and harvest metadata records. For more technical information on this protocol please see either website below:
As a brief summary, the OAI-PMH defines two classes of participation:
The underlying technology involves:
The protocol policies require:
The description of the harvesting protocol includes request/response types, with the following six request types defined:
In order to be a Data Provider, an existing archive must:
A list of archive policy decisions is useful also.
The OAI metadata record has the following sections:
Last updated: 5-22-02