04 August 2011

Et DONA ferentis?

If you've been reading papers in the past few years you would have seen DOIs in the references. (I mean academic papers, not newspapers.) The idea is that it saves you from writing

Journal of Theoretical and Applied Irrelevance, 53 Vol. 3 (1), (2008), pp.312-322.

when instead you can write a simpler string, a handle, which identifies the data.

For this to work, you will need a handle resolution service. Think of DNS. If you did it "by hand" you would resolve www.gridpp.ac.uk with:
dig www.gridpp.ac.uk. A IN
to an IP address, and then maybe telnet to port 80 or something. Or think of the GUID-to-SURL mapping in LFC that we all know and love (or the SURL-to-TURL mapping). Similarly, handles have to resolve into something that is the stuff you're looking for. Doesn't have to be a paper, it could also be data, or even particular versions of data.

Enter the Handle System. Patrice Lyons and Bob Kahn - one of the fathers of the Internet - from CNRI, are proposing to establish a global handle system, morally equivalent to ICANN, to manage the uniqueness and persistence of handles. This will be the Digital Object Numbering Authority, or DONA.

Of course, like DNS or GUIDs, there is no assurance that the data you're looking for is actually there. In fact, persistence is meaningful even for temporary objects, in the sense of the handle being associated with the object forever, even if the object itself doesn't live forever.

Sounds simple? Well, apart from those temporary objects, the system may need to be able to deal with modifiable objects, versions, replicas, and (possibly) part handles. Typing it in again from a printed representation. And what is the object? is it the object as a sequence-of-bits, or is it the "curation-object" which goes in as a Word97 document, say, and is referenced later as PDF.

We might even have a GFAL-type library which knows how to resolve handles into data, so the application doesn't have to know. Meanwhile, the handles are coming: apart from the publishers' DOIs in the papers, you can see the entertainment industry have also picked it up with EIDR.