The actual "handle" is "10.1074/jbc.M004545200 ".  If your software 
wants to get a "handle" to give it to any handle resolver of it's 
choice, it's going to have to parse the "doi:" or "info:" versions to 
get the handle out first.  The info version is a URI that has a DOI 
handle embedded in it.  The doi version is... um, I dunno, just a 
convention, I think, that has a DOI handle embedded in it.

Likewise, if your software had a URI, and was smart enough to know that 
the URI "http://dx.doi.org/10.1074/jbc.M004545200" actually had a handle 
embedded in it, it could strip the handle out, and then resolve it 
against some other handle server that participates in the handle 
network, like hdl.handle.net.  But that would be kind of going against 
the principle to treat URI's as opaque identifiers and not parse them 
for internal data.

But me, I end up going against that principle all the time in actual 
practice, actually for scenarios kind of analagous to, but less 
well-defined and spec'd than, getting the actual "handle" out of the URI 
and resolving it against some other service. For instance, getting an 
OCLCnum out of an http://worldcat.oclc.org/ URI, to resolve against my 
local catalog that knows something about OCLCnums, but doesn't know 
anything about http://worldcat.oclc.org URIs that happen to have an 
OCLCnum embedded in them. Or getting an ASIN out of a 
http://www.amazon.com/ URI, to resolve against Amazon's _own_ web 
services, which ironically know something about ASIN's but don't know 
anything about www.amazon.com URI's that have an ASIN embedded in them.  
Actually quite analagous to getting the actual handle out of an 
http://dx.doi.org or http://hdi.handle.net URI, in order to resolve 
against the resolver of choice.

Jonathan

Ross Singer wrote:
> On Mon, Nov 23, 2009 at 2:52 PM, Jonathan Rochkind <[log in to unmask]> wrote:
>
>   
>> Well, here's the trick about handles, as I understand it.  A handle, for
>> instance, a DOI, is "10.1074/jbc.M004545200".
>>     
>
> Well, actually, it could be:
> 10.1074/jbc.M004545200
> doi:10.1074/jbc.M004545200
> info:doi/10.1074/jbc.M004545200
>
> etc.  But there's still got to be some mechanism to get from there to:
> http://dx.doi.org/10.1074/jbc.M004545200
> or
> http://dx.hellman.net/10.1074/jbc.M004545200
>
> I don't see why it's any different, fundamentally, than:
> http://purl.hellman.net/?purl=http%3A%2F%2Fpurl.org%2FNET%2Fdoi%2F10.1074%2Fjbc.M004545200
>
> besides being prettier.
>
> Anyway, my argument wasn't that Purl was technologically more sound
> that handles -- Purl services have a major single-point-of-failure
> problem -- it's just that I don't buy the argument that handles are
> somehow superior because they aren't limited to HTTP.
>
> What I'm saying is that there plenty of valid reasons to value handles
> more than purls (or any other indirection service), but independence
> to HTTP isn't one of them.
>
> -Ross.
>
>   
>> While, for DOI handles, normally we resolve that using dx.doi.org, at
>> http://dx.doi.org/10.1074/jbc.M004545200, that is not actually a requirement
>> of the handle system. You can resolve it through any handle server, over
>> HTTP or otherwise. Even if it's still over HTTP, it doesn't have to be at
>> dx.doi.org, it can be via any handle resolver.
>>
>> For instance, check this out, it works:
>>
>> http://hdl.handle.net/10.1074/jbc.M004545200
>>
>> Cause the DOI is really just a subset of Handles, any resolver participating
>> in the handle network can resolve em.  In Eric's hypothetical use case, that
>> could be a local enterprise handle resolver of some kind. (Although I'm not
>> totally sure that would keep your usage data private; the documentation I've
>> seen compares the handle network to DNS, it's a distributed system, I'm not
>> sure in what cases handle resolution requests are sent 'upstream' by the
>> handle resolver, and if actual individual lookups are revealed by that or
>> not. But in any case, when Ross suggests -- "Presumably dx.hellman.net would
>> need to harvest its metadata from somewhere, which seems like it would leave
>> a footprint. It also needs some mechanism to stay in sync with the master
>> index." -- my reading this suggests this is _built into_ the handle
>> protocol, it's part of handle from the very start (again, the DNS analogy,
>> with the emphasis on the distributed resolution aspect), you don't need to
>> invent it yourself. The details of exactly how it works, I don't know enough
>> to say.  )
>>
>> Now, I'm somewhat new to this stuff too, I don't completely understand how
>> it works.  Apparently hdl.handle.net can <strike>handle</strike> deal with
>> any handle globally, while presumably dx.doi.org can only deal with the
>> subset of handles that are also DOIs.  And apparently you can have a handle
>> resolver that works over something other than HTTP too. (Although Ross
>> argues, why would you want to? And I'm inclined to agree).
>>
>> But appears that the handle system is quite a bit more fleshed out than a
>> simple purl server, it's a distributed protocol-independent network.   The
>> protocol-independent part may or may not be useful, but it certainly seems
>> like it could be, it doens't hurt to provide for it in advance. The
>> distributed part seems pretty cool to me.
>>
>> So if it's no harder to set up, maintain, and use a handle server than a
>> Purl server (this is a big 'if', I'm not sure if that's the case), and
>> handle can do everything purl can do and quite a bit more (I'm pretty sure
>> that is the case)... why NOT use handle instead of purl? It seems like
>> handle is a more fleshed out, robust, full-featured thing than purl.
>>
>> Jonathan
>>
>>
>>
>>
>>     
>>> Presumably dx.hellman.net would need to
>>> harvest its metadata from somewhere, which seems like it would leave a
>>> footprint.  It also needs some mechanism to stay in sync with the
>>> master index.  Your non-resolution service also seems to be looking
>>> these things up in realtime.  Would a RESTful or SOAP API (*shudder*)
>>> not accomplish the same goal?
>>>
>>> Really, though, the binding argument here is less the issue here than
>>> if you believe http URIs are valid identifiers or not since there's no
>>> reason a URI couldn't be dereferenced via other bindings, either.
>>>
>>> -Ross.
>>>
>>>
>>>       
>
>