Re: DOI and other identifiers

Hi Dan,

I find your arguments below compelling. It did come up elsewhere in the thread whether annotations couldn't be born with DOI-s in the first place, but I am not sure it is realistic (although worth exploring).

Where do we go from here? But let us explore what it would mean to add something for this into the model. The main issue, I believe, is that we should certainly not concentrate on DOI-s only. DOI-s are used in a very particular area (scholarly publishing) and ignored in other areas (eg, book publishing). While annotations are not books, ie, they would not get an ISBN, we cannot exclude that, in some other areas, we get other identifier schemes of that sort. Ie, the extension to the model should look like (make-up terms for now):

"externalIdentifier" : {
	"authority" : "e.g. DOI",
	"identifier": "the DOI assigned to the annotation"
}

The system should treat an "externalIdentifier" just like it does for canonical identifier insofar as it must not change it, it is some sort of a metadata that is carried with the annotation. Also, the model could allow for several external identifiers by giving an array of such structures.

Of course, the problem is the 'authority' term. There may be many of those. There are many of those. How do we identify them? Are there canonical (sic!) identifiers or terms for them? How should we define/find those? These are not obvious issues when it comes for interoperability.

B.t.w., the IDPF EPUB3.1 WG is facing the same issue right now: how to define the various identifiers that an EPUB may have. The current, proposed, approach (with a different syntax) is that IDPF sets up a registry for the authorities, ie, a list where terms like "DOI", "ISBN", etc, are listed and mapped on URI-s that describe those. I do not mean we should set up such registry but, after all, we may also declare that we use the IDPF registry (the only caveat is that I am not sure when that registry will become operational, but that is more of a process issue).

I am not sure we would want to go down that route; maybe what I just outlined should fall into the realm of extension to the current vocabulary (thereby following Doug's approach as he mentioned on the call), ie, not something the group has to do now. We can add this as an informative example for an extension into the document, and leave it there for now (with a possible inclusion into a V2). I am undecided at this point, I must admit.

Ivan


> On 7 May 2016, at 13:04, Dan Whaley <dwhaley@hypothes.is> wrote:
> 
<snip>
> 
> 
> * Is the DOI the canonical identifier for the Annotation?
> 
> So I may be off base here, but I think there are perhaps two different senses of the word "canonical" at play here.
> 
> From an annotation systems perspective, it seems unlikely that the DOI is ever going to be canonical in the sense that it becomes the *primary identifier* replacing the one we minted originally.  We'll want to use a consistent identifier for all our annotations internally, not different ones depending on whether a DOI was issued.  (What if someone captured the URL of the annotation *prior* to the DOI issuance?  We can't ourselves fail to resolve the "old" address of the annotation.)  I assume there may even be performance issues underlying this.  This is perhaps more true of annotation systems than regular publications because annotations would be born without DOIs and presumably get them later, and I'm not imagining that would change.  Otherwise we'd be issuing DOIs for every trivial annotation from inception, and that indeed would be massive.
> 


----
Ivan Herman, W3C
Digital Publishing Lead
Home: http://www.w3.org/People/Ivan/
mobile: +31-641044153
ORCID ID: http://orcid.org/0000-0003-0782-2704