On Thu, 18 Sep 2003, Tony Linde wrote:
> <<I hope that the registry will be able to tell me which services exist
> that can recognise an ID that matches the ivo://NASA/HST part >>
The above appears to be asking about service discovery for data access services that can return data from a data resource (collection) called ivo://NASA/HST. In this case there can be many registered services which can return data from the above referenced resource, a data collection. Also the data collection may be replicated at multiple locations.
> The registry will tell you the ONE resource that matches ivo://NASA/HST,
> since this is a unique resource identifier (where NASA is the AuthorityID
> and HST is the ResourceKey). The metadata returned for that resource will
> tell you the URL of that web service. The standard methods of such a service
> are yet to be agreed, but I would assume one is a doQuery(string AdqlQuery)
> type of method.
This however appears to refer to how one queries the registry for the metadata for a specific registered resource such as a data collection. I am not sure what the web service is that is being referred to. What does this web service do - is it part of the registry mechanism? If it is a data access or other such service I would not expect it to be referenced in the registered metadata for the data collection. There may be any number of such services that reference a particular resource such as a data collection, hence they must be registered and described independently. Dynamic discovery, via registry queries, is where the association is made.