multiple capabilities of the same kind

[Doug Tody]

Hi Ray -

This is good, except that the DataCollection resource should probably
not point to services.  Rather, the services should point to the data
collection or collections they serve, and a query should be used to
find services which serve data from the desired data collection.

The problem is that a service always knows what data collections
it serves, but a data collection resource should merely describe
a data collection, and cannot reliably know how it is referenced.
Many services from different locations might reference the same
data collection.  If data is replicated this relationship can vary
dynamically.

	- Doug


On Fri, 15 Feb 2008, Ray Plante wrote:

> On Fri, 15 Feb 2008, Paul Harrison wrote:
> > It seems that the motivation behind this is that each capability gives
> > access is a different subset of the overall data set, other than that, the
> > capability metadata are identical except for the different endpoints (and
> > description elements) for each subset.
> 
> Okay--good.  I would say that the ideal way to register these would be:
> 
>   1.  A DataCollection resource describing the image archive.  It should
>       include the references to the SIA resources as "served-by" related
>       resources.
> 
>   2.  A CatalogService with SIA capability for the first collection
>       subset.   It can have a "service-for" relationship to the above
>       DataCollection resource.
> 
>   3.  A CatalogService with SIA capability for the second collection
>       subset.   It, too, can have a "service-for" relationship to the
>       above DataCollection resource.
> 
> hope this helps,
> Ray
>