[Esip-preserve] Identifiers Use Cases

[Curt Tilmes]

Ruth Duerr wrote:
> However, I think it is the citation that needs that, not the  
> identifier for the data set.

Yes.  That is one of the differences in the examples I showed for DOI
vs. PURL.  It is trivial to produce thousands of PURL identifiers, so
it makes sense to put the full qualification in the indentifiers.  For
DOI, not so much, so I added an additional qualifier (in my proposed
case, the date/time) to the citation.  You distinguished identifiers
from citations with better wording on the main page.

> I also think that, as you suggest in your use cases, the time of
> access is one possible mechanism for doing that

We also looked at some hashing schemes or even arbitrary identifiers
that mapped to sets of granules, but nothing was as clean and easy to
use (and understand) for users or implementers as date/time.

> (and that is probably the simplest mechanism from a citation
> standpoint though not necessarily from a user standpoint if for no
> other reason than it might have taken the user a month to download
> all the data they used and the data set may have undergone a whole
> host of updates over that time period).

Ok, take that case.  How should we propose to handle it?

In my scheme, the date/time in the citation is a point in time, so you
could either:

1. grab the original set of granules that were existing at the time
you start that long month of downloads and cite that date/time.

or 2. double check the data set and grab any updates and cite the
later date/time.

How else could we approach it and still maintain the precision of
citation?

Curt