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Re: Final CFP: In-Use Track ISWC 2013

From: Phillip Lord <phillip.lord@newcastle.ac.uk>
Date: Fri, 10 May 2013 15:34:18 +0100
To: Norman Gray <norman@astro.gla.ac.uk>
Cc: Sebastian Hellmann <hellmann@informatik.uni-leipzig.de>, Linking Open Data <public-lod@w3.org>
Message-ID: <87vc6qsy39.fsf@zerg32.ncl.ac.uk>
Norman Gray <norman@astro.gla.ac.uk> writes:
>> Norman Gray <norman@astro.gla.ac.uk> writes:
>>>> I am not completely familiar with DOI. Am I right, that it more or less
>>>> provides the same service as http://purl.org .
>>>> DOI links on the resource-level. You would still need frag ids to link to parts.
>>>> Firefox can actually handle this:
>>>> http://dx.doi.org/10.1038%2Fscientificamerican1210-80#atl
>>> It's not the same thing as purl.org.
>> The mechanism by which DOIs and purls are resolved is more or less
>> identical. Under the hood, DOIs use handles, purl.org uses a triple
>> store. In practice, users don't interact with either directly.
> Well, yes and no. The distinction I was thinking about was that PURLs are
> _defined_ in terms of an HTTP redirect (the triple store behind it is an
> implementation detail), whereas DOIs are defined in terms of the underlying,
> distributed, Handle system. There, the dx.doi.org URL is 'just' a convenience
> layer on top of the 'real' API.

They are, indeed, although as far as I can see, in general, the only
people who interact with the handle system are people like crossref and
datacite. So, while I accept this point, I think it doesn't make any

> I don't think this is just a quibble, because this, plus the different
> sustainability model, effectively gives the DOIs different persistence
> properties from PURLs. Whether those different properties are _practically_
> different is of course a different question. Myself, I'm broadly doubtful that
> there's a massive practical difference; but although I'm unpersuaded by it, I
> can see the force of the argument that the DOI sustainability model is of
> crucial importance.

I think, here, you need to separate the organisational details from the
technical ones. DOIs are all run by the DOI foundation. But there are 8
different registration authorities, and they have different models. None
the less, there is a degree to which the DOI comes in built with a
social contract.

PURLs, on the other hand, do not. So, the PURLz server at www.purl.org,
the one at purl.bioontology.org and the one that I run on my local
machine so I can play with it, all have very different contracts.

>From the social point of view, comparing DOI with PURL doesn't make
sense. You need to compare, DOIs from mEDRA, with the PURL server at

> The other argument for DOIs is that 'http:' refers to a transport protocol,
> which is being hijacked as an identifier scheme, and will presumably be
> replaced by whatever replaces HTTP over the coming decades. I think this
> argument, also, is initially attractive but unpersuasive in detail, but it
> doesn't even arise for 'doi:', which is an identifier scheme by definition.

Also, I agree unpersuasive. First, the standard guidelines for display
of (CrossRef) dois now says "http://dx.doi.org/10.xxxx"; so even if this
is widely ignored, and change of http:// to pantp:// (Phil's
all-new-transport-protocol) would affect this also. Second, because if
http: ever changes and becomes less popular, it will happen slowly and
have so many effects that a general solution would be found.

>>>> If I am right, DOI also wouldn't be able to provide links to the 40
>>>> million mentions contained in the Wiki links corpus:
>>>> http://techcrunch.com/2013/03/08/google-research-releases-wikilinks-corpus-with-40m-mentions-and-3m-entities/
>>>> That's 40 million DOIs ....
>>> I don't there would be such DOIs, unless someone has spent quite a lot of money registering them.
>> A purl would be much better in this case anyway, since purls support
>> partial redirection, which to my knowledge, DOIs do not. With DOIs you
>> would need 40 million DOIs. With purls, you would create a single
>> partial redirect purl and handle the rest locally.
> I've been on the fringes of Datacite discussions, so don't know the fully
> up-to-date details, but I believe that one of the use-cases, in discussions
> about the pricing structure, is the case where someone _does_ want to register
> millions of DOIs per year (or billions: what about a DOI for every LHC
> event?). I _think_ the resolution to the 40M DOIs question is "don't do that,
> then", but the question has crossed the Datacite people's minds, and the
> different Datacite registries have (I understand) different pricing models for
> different DOI volumes.

Or an effectively infinite number of DOIs -- you can do this with PURLs,
but not with DOIs. At this scale, DOIs do not work, because they are
preregistered. PURLs do just fine, since with a partial redirect and a
deterministic algorithm, you can create them lazily.

Received on Friday, 10 May 2013 14:34:42 UTC

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