role of the registry

[Keith Noddle]

I like to think of it this way: Bob's right, Tony's right and Matthew is 
right. Now let's go an have a beer or three!

Seriously, the Registry is a way to discover resources. Tick for Bob's 
argument. If a VO project chooses to keep it to that, good for them. 
However, a different VO project might choose to extend the Registry to 
hold additional information. Tick for Tony. Provided these two different 
registry implementations can exchange the mandatory minimum data to 
harvest each other, there is no problem. Data Dictionary: the single 
best place to provide metadata about a resource is with the service that 
serves up that resource. Tick for Matthew (the "Data Dictionary 
infrastructure" turns out to be the collective, distributed metadata 
provided by each service, the mechanisms for providing which are being 
discussed elsewhere). Everything else is an implementation detail - and 
we're good at that.

Maybe I'm being too simplistic, but where's the problem?

> I'm inclined to agree with Bob. We invented the registry as an 
> alternative to UDDI, which did not do exactly what we wanted, for 
> resource discovery and not as a generic metadata store. As I have said 
> before, we can overload the registry concept and use the existing 
> infrastructure (plus some epicyclic extensions) to provide general 
> metadata stores or we can separate these and keep the registry simple 
> and create a different kind of infrastructure for the data dictionary 
> stuff.

Keith.

-- 
Keith Noddle                    Phone:  +44 (0)116 223 1894
AstroGrid Project manager       Fax:    +44 (0)116 252 3311
Dept of Physics & Astronomy     Mobile: +44 (0)7721 926 461
University of Leicester         Email:  ktn at star.le.ac.uk
Leicester, UK   LE1 7RH         Web:    http://www.astrogrid.org