The Naval Research Laboratory’s Ongoing Implementation of the Open Geospatial Consortium’s Catalogue Services Specification

located at Stennis Space Center, conducts research involving the online storage and manipulation of geospatial data. One aspect of this research concerns metadata. Metadata is “data about data ” or simply put, various bits of information that provide an understanding of certain aspects of the data such as source, resolution, date created, geographic location and many others. Standardized metadata formats allow data to be easily categorized and thereby easily searched. Most geospatial data producers have realized or are starting to realize that creating standardized metadata along with their data is crucial for allowing their data to be utilized by standards-conforming Geographic Information Systems (GIS). But having the metadata in standard formats is only part of the solution. How can this metadata be stored, updated and queried in a standard way? To this end, the Open Geospatial Consortium (OGC) has created an open specification for cataloging metadata. This specification is named “Catalogue Services ” and defines a base metadata and interface model to allow querying and updating a metadata catalog. The base model is an abstraction that is actualized by a “protocol binding”. A protocol binding defines the mapping between the interfaces of that binding and those of the base specification. The Catalogue Services specification defines CORBA, Z39.50 and HTTP protocol bindings. The HTTP protocol binding is also known as “Catalogue Services for the Web ” (CSW). The Catalogue Services specification also defines the concept of “application profiles ” which allows the base model to be extended to support a particular user community’s needs. The base catalog specification, protocol bindings, and application profiles together provide a very flexible and powerful metadata cataloging architecture