[utypes] Data Model URIs

[Markus Demleitner]

Dear List,

On Mon, Nov 28, 2011 at 06:06:58AM -0700, Douglas Tody wrote:
> One thing I think we missed here is that the Utype namespace should
> have an associated URL where information about the DM can be looked up
> online in an automated fashion.  This should include being able to

I'd strongly advocate using the <prefix>:DataModel.URI mechanism as
suggested in the note on STC in VOTables
(http://www.ivoa.net/Documents/Notes/VOTableSTC/).  

The issue with the "automated" part (i.e., what's supposed to
happen when someone tries to dereference the URI) is another one
altogether.  My take on this is: We'd need clear use cases what
a tool would do with whatever information is at the other end.  Since
I'm not aware of any such use cases, I'd say we should let that open
for a first utypes document.  

I'd not argue against a recommendation that XSD should come back if
the namespace URI is an HTTP URL, though; I could imagine some
potentially useful things one could do with that.

Cheers,

        Markus