This is the starting point for developing a model of entities with which a registry needs to engage. To start with, we'll simply create a list of 'things' and add definitions to them:
resource
an item (with an identity) which is of interest or use to the Virtual Observatory community
service
a resource which can be invoked Note: service sub-types such as ConeSearch or SIAP are still considered to be services, not interfaces
interface
a physical, technical interface to a service
organisation
any type of organisation
site
a single location
publisher
an organisation responsible for creating and maintaining a resource
provider
an organisation responsible for making a serviceavailable Note: since only services are invocable then only they ought to have a provider
data collection
a collection of datasets (or other collections)
copy
a complete copy of a data collection Note: properties of the copy will represent the period a mirror is updated, the date/time a snapshot was taken etc. Note: copies of less than the whole data collection will form new collections with a 'derived from' relationship, much as the results of a query would have
snapshot
a copy of a data collection which is never updated
mirror
a copy of a data collection which is periodically updated
dataset
a single published set of data tables from a science team
table
a set of data in which all rows have the same columns (??)
application
a collection of functions
function
a process that transforms data, generates information, etc. Note: I'm fairly sure we need both application and function but could do with better definitions
sky service
a service that makes one or more data collections available
tabular sky service
a specific type of sky service: one which accesses and returns tabular data
app service
a service that makes one or more applications available