EOS Clearinghouse

ECHO is the EOS clearinghouse. It is a web-accessible database containing inventories of participating ESE data system holdings. ECHO does not maintain the data or provide direct services on the data, but rather provides a central site for access to detailed information about data holdings at the various data systems (called ECHO providers). ECHO also maintains metadata describing data services. ECHO functionality goes beyond the GCMD catalog by including not only dataset level information, but also granule-by-granule inventory information and also information necessary to facilitate order of data from the data providers.

ECHO is a new system, having been developed by iterative operational release over the past several years. The current version of ECHO is capable of receiving inventory metadata from ECS as well as from some of the "Version Zero" systems. It is anticipated that inventory publication to ECHO may become a future requirement for ESE funded data systems.

To publish data holding metadata to ECHO, the data provider must provide a mapping of their data inventory database into the ECHO data model. The ECHO operations group is charged with helping providers develop this mapping.

ECHO's science metadata model is derived from the ECS science metadata model with some extensions and simplifications. ECS data model in turn was developed in parallel to the FGDC model. Metadata conformant with ECS or generally with FGDC can be fairly straightforwardly mapped to ECHO. The ECHO data model is represented in XML and if the provider data model is also represented in XML the mapping is instantiated as an XSLT. Conformance is verified by XML schema.

Definitions and valid value rules for the metadata model entities and attributes are not presently available on-line but they generally follow the ECS heritage.

Please see the echo website for more information. DTD representing the ECHO collection and granule science data model