VO and ADEC identifiers

[Arnold Rots]

Two comments.

One is that I thought we had reverted to Greg's "Sa" designations.

The other is that it seems to me that the split between authority Id
and resource key for ADS identifiers is rather useless.
I would suggest that we return to the two-key design:

	<AuthorityId>/<DatasetId>

This could result in things like:

	Sa.CXO/4000
	Sa.HST/STIS/O4LT010E0
	Sa.HST/WFPC2/U32L0104T
	Sa.IUE/LWP25899

However, if HST would like to register STIS and WFPC2 as separate
entries, they could be changed to:

	Sa.HST.STIS/O4LT010E0
	Sa.HST.WFPC2/U32L0104T

In other words, allow the naming authority to register subtypes in the
authority Id field by appending them to the root authority Id,
separated by a '.'.

  - Arnold

Alberto Accomazzi wrote:
> Hi Arnold and Ray,
> 
> I've also been thinking about Ray's proposal, and in the last couple of 
> days I have read up on the IVOA identifier WD and spoken to both 
> Guenther and Arnold about this.
> 
> I think the proposal is good and can be adopted for use by the ADEC 
> dataset linking/verification system.  For the sake of clarity (and to 
> confirm that I am fully understanding what Ray is proposing) let me 
> restate a few things.  Ray, please let me know if this matches up with 
> what you have been thinking.
> 
> The identifier to be used in journals to refer to a dataset will be in 
> the form:
> 
> 	authorityID/datacollection#PrivateID
> 
> where both "authorityID" and "authorityID/datacollection" have entries 
> in the registry.  PrivateID can be anything the authorityID has chosen 
> it to be, and represents a unique identifier that has been assigned to a 
> dataset within the particular data collection.
> 
> For instance, MAST has a number of missions it holds data for, each with 
> a set of datacollections available (see 
> http://archive.stsci.edu/dataset_verifier.html).  Assuming the 
> authorityID of "NASA.HST" has been created for the HST mission , the 
> identifiers for its datasets would look something like this:
> 
> 	NASA.HST/STIS#O4LT010E0
> 	NASA.HST/ACS#J8FF03021
> 	NASA.HST/WFPC2#U32L0104T
> 	...
> 
> I'm not sure what to do with missions that do not currently have 
> explicit datasets defined for them, e.g. IUE.  One solution would be to 
> allow the identifiers to have an empty datacollection:
> 
> 	NASA.IUE/#LWP25899
> 
> This would be akin to being able to specify URLs of the kind 
> http://ads.harvard.edu/ rather than http://ads.harvard.edu/index.html, 
> but it complicates things a bit when it comes to implementing the 
> registry lookup, since NASA.IUE would have to appear as both an 
> authority ID and a datacollection.  Or maybe we should similarly 
> stipulate that a default data collection name should be used if none has 
> been specified.
> 
> Also, while we're at it, I would suggest specifying an explicit scheme 
> prefix to indicate what domain these identifiers belong to.  I'm 
> thinking of simply prepending vo: or vo:// to it, like Ray has specified 
> in the VO identifier WD:
> 
> 	vo://NASA.HST/STIS#O4LT010E0
> 
> This will clearly mark the identifier unanbiguously as something that 
> needs to be resolved against the VO registry.  It also means that in 
> principle we can mix identifiers of different kinds in our documents and 
> leave the resolution to the appropriate authorities and tools.  This is 
> similar to what the DOI foundation does for their own identifiers, which 
>   use a syntax of "doi:authority/object_id"  (Speaking of DOIs, there is 
> no reason in my mind why we could not make use of them as well, but I'll 
> save that for another discussion).
> 
> I still have some questions about how the deployment of resolvers should 
> take place both in the short and in the long run, but I don't see a 
> reason why this should stop us from adopting this syntax right away.
> 
> 
> -- Alberto
> 
> 
> ****************************************************************************
> Alberto Accomazzi
> NASA Astrophysics Data System                     http://adswww.harvard.edu
> Harvard-Smithsonian Center for Astrophysics      http://cfa-www.harvard.edu
> 60 Garden Street, MS 31, Cambridge, MA 02138 USA
> ****************************************************************************
> 
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Arnold H. Rots                                Chandra X-ray Science Center
Smithsonian Astrophysical Observatory                tel:  +1 617 496 7701
60 Garden Street, MS 67                              fax:  +1 617 495 7356
Cambridge, MA 02138                             arots at head-cfa.harvard.edu
USA                                     http://hea-www.harvard.edu/~arots/
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