Hi,

I have some questions on relationship between OGC Catalogue Service and Clearinghouse:

I saw “Clearinghouse is equivalent to the OGC’s Catalogue Service.” at http://www.gvsig.gva.es/index.php?id=glosario&L=2. But I don’t think so.

1. Has OGC developed its Catalogue Service using Clearinghouse of NSDI for reference, and has made some improvement based on Clearinghouse? Or Has Clearinghouse of NSDI been developed complying with OGC’s Catalogue Service specification?

2.If there are some difference between OGC Catalogue Service and Clearinghouse of NSDI, what’s the main difference?

3.Can a self-design node, which complys with OGC’s Catalogue Service specification, register to Clearinghouse?

Thanks,
Zhou

The OGC Catalogue Service Specification was co-developed with input from FGDC, NASA, NGA (then NIMA), Canada GeoConnections, and several vendors. The OGC Catalogue spec is an "abstract" specification that defines general search behavior of a catalogue and then has sections that defines three specific protocol bindings, or software deployment environments. These are CORBA, Z39.50, and HTTP. The NSDI Clearinghouse has implemented the Z39.50 protocol and is therefore compliant with the OGC Catalogue spec. More recently, the new search portal for Clearinghouse (Geospatial One-Stop, geodata.gov) does allow for the registration and search of the OGC HTTP binding of catalogue, also known as "Catalogue Service for the Web, CS-W".

Metadata providers may set up metadata services in several ways that are accessible to geodata.gov (thus part of the Clearinghouse):

1. Post metadata in a web-accessible folder and register with geodata.gov
2. Upload FGDC metadata XML files to geodata.gov
3. Enter metadata in a form on the geodata.gov site
4. Register a Z39.50 server (OGC Catalogue compliant)
5. Register a CS-W metadata service (OGC Catalogue compliant)

Doug Nebert
ddnebert@fgdc.gov