OASIS Mailing List ArchivesView the OASIS mailing list archive below
or browse/search using MarkMail.


Help: OASIS Mailing Lists Help | MarkMail Help

xri message

[Date Prev] | [Thread Prev] | [Thread Next] | [Date Next] -- [Date Index] | [Thread Index] | [List Home]

Subject: Re: [xri] PILIN docs and Abstract Identifier Architecture paper

Drummond has asked for my thoughts about the  
AbstractIdentifierArchitecture page.

The new draft includes language which address the concern I had  
expressed to Drummond over the weekend, and Dan Connolly had  
independently raised at http://lists.w3.org/Archives/Public/www-tag/2008Sep/0083.html 
  --- identifiers are only ever abstract or concrete, as the page  
defines it, with regard to a given resolution service (or protocol, as  
the page terms it).

Since both HTTP and XRI have one primary resolution method in mind,  
the constraint is appropriate --- although it makes HTTP go into loops  
when you do want to resolve to descriptors instead of resources: you  
clearly can't do so in the same resolution method, as the page  
concludes. That said, an identifier to us is just an association of a  
name with a referent; when we start constraining how that identifier  
resolves, we're no longer talking about identifiers per se --- but  
resolution requests. Conflating an identifier with a request to  
resolve an identifier (concretely or abstractly) is always perilous,  
and I'd keep adding "in the context of a given communications  
protocol" continuously --- especially as you're switching protocols  
between XRI and HTTP (even if at a conceptual level, and not a  
physical transport).

I'd just add the caveat that even in a single protocol, there's more  
than one way to resolve an identifier. For instance, OpenURL takes  
URIs as parameters, and resolves them differently to what the default  
resolution is (if any); and XRI crossreferences seem to me to be  
heading the same way. (For that matter, XRI-through-HTTP is  
conceptually a different kind of resolution from vanilla HTTP.) So  
while it may be obvious that =drummand, =drummond(+descriptor), and http://xri.net/=drummond?_xrd_r=application/xrds+xml 
  are not the same identifier, I'd say that explicitly (and include  
something like =drummond(+descriptor) .)

Oh, and with the Handles, I think the examples are misleading.  
Inasmuch as http://dx.doi.org/10.1000/182 is an HTTP GET, what it gets  
is the representation, not the descriptor: it is truly a synonym of http://www.doi.org/hb.html 
  . The descriptor of doi:10.1000/182 is in the first instance the  
Handle record, e.g. http://nascent.nature.com/openhandle/handle?id=10.1000/182&format=rdf&mimetype=application/xml 
  ; if the DOI metadata was exposed as a service, I'd link to that  
instead, since they're clearly not using Handle to encode their  
descriptors. (Try http://nascent.nature.com/openhandle/handle?id=10000.2/m.donoghue&format=rdf&mimetype=application/xml 
  for a more heavy-duty Handle-based descriptor --- as opposed to  
hdl.handle.net/10000.2/m.donoghue , which is a representation. (A lame  
one, but I don't think Handle have taken descriptors seriously yet.)

  Dr Nick Nicholas,      opoudjis@optushome.com.au    Link Affiliates,
  http://www.opoudjis.net      skype:opoudjis               Melbourne.
  "There is a danger, my dear Neophron, that they will go further, and
   conceive a contempt for the stress-accent as something very trivial,
   and will decree that any group of words of any kind is a verse."
  --- Maximos Planudes, predicting free verse and worse, late xiii AD.

[Date Prev] | [Thread Prev] | [Thread Next] | [Date Next] -- [Date Index] | [Thread Index] | [List Home]