Links and Resources
6. Metadata catalogue
The metadata catalogue offers the possibility to systematically search and find the documented spatial data and services. It stores and manages the indexed and searchable metadata “against which intelligent geospatial search can be performed within or among SDI communities” (GSDI Association, 2009). The mechanism to classify, register, describe, search, maintain and access information on geodata and services is defined differently within geospatial community: repository, metadata registry spatial data directory, clearinghouse etc.
If metadata is valid, then it is stored in the catalogue under approved status. Otherwise, additional editings of the metadata items are required before they are accepted as valid metadata entries.
Metadata can be published using an online metadata editor embedded on the same platform where the Catalogue Service is running or can be generated using desktop Editor and then imported into the implemented catalogue service.
To allow metadata query and harvesting across distributed platforms, the catalogue services have to be aligned to the existing cataloguing standards. Some of the available standardization efforts dedicated to the metadata catalogue services are outlined below:
• ISO 23950 Search and Retrieve Protocol (ANSI Z39.50) has been developed for the library community for accessing virtual catalogs;
• OGC Catalogue Services Specification;
• ebRIM (ebRIM (Electronic business Registry Information Model) is a meta model developed by the Advancement of Structured Information Standards (OASIS) for documenting and managing metadata items in a web catalog (OGC, 2007).
Catalogue services are required to support the discovery and binding to registered information resources within an information community.