Download Location of war: http://www.astrogrid.org/maven/org.astrogrid/wars/
See astrogrid-registry-???.war where ??? is a version number. Look at dates for latest release. The registry is based around metadata for virtual observatories based on IVOA standards IVOA website. A registry holds vast amounts of metadata for particular Resources. A Resource can be a data sets, web services, services, information on other registries. For the registry to be interoperable with other registries in other varous virtual observatories, the registry must conform to an international recognized schema. The registry currently conforms to the IVOA Resoruce metatadata schema. See the IVOA website for the current schema. Astrogrid is one of the first implementors of a VO trhough a grid, because of this Astrogrid is ahead of IVOA standards causing some implementations or standards to be extended, recently the registry metadata has been extended to allow for particular specefic applications metadata to be entered into the registry.
See the webapp section for documentation on how to install the registry and how it runs
The registry gathers its information from either user input by file, url, or through the portal. Or more commonly most metadata is obtainged through harvesting. Which is a means of reading in a url or web service described in the metadata (usually of another Registry) and make a call to extract the metadata from one resource and place it in the current registry.
Retgistry main objective is for the use of querying the registry to gain information about Resource or Resources to be obtained by other registries. This information can then be used for these other components. Here is a quick look at other components and the use they have for Registry.