event identifiers

[Ray Plante]

Hi VOEvent-ers

On Thu, 14 Apr 2005, Arnold Rots wrote:
> I will comment only on one point - the identifiers.
> I would suggest that maybe the authority for VOEvents should be, well,
> VOEvent which would assign resource Ids to trusted publishers.
> Hence, the identifiers would look like:
> 
> 	ivo://VOEvent/<publisher>#<event id>

As editor of the IVOA Identifier spec, I thought I might offer some 
comments on this.  Obviously, I've not been in Pasadena for the 
workshop, and I've not kept up with the email discussion, so pardon if 
some of this is naive.  

Remember that the "ivo:" scheme means that there is supposed to be a 
record in an IVOA registry describing a resource with that ID (up to but 
not including the #).  Furthermore, an authority ID--that is, VOEvent, in 
this example--is controlled by a single organization.  In practical terms, 
this means the following:

   1.  The VOEvent authority ID is registered in an IVOA registry.  That 
       is, there is a record in the registry with the ID "ivo://VOEvent" 
       and with a publisher set to a registered organization.

   2.  For an organization to be registered, there is a record in the 
       registry describing the organization.  

So, this scheme essentially says that there is a central organization that 
assigns IVOA identifiers to be used to identify events.  Who is that 
organization going to be?  I can see this being appropriate if you are 
having all events flow through one event channel; this would give users 
only one channel they have to monitor.  

cheers,
Ray