XRI

["Bryan Rasmussen" <BRS@itst.dk>]

Hi,

XRI is pretty well described in the FAQ
http://xml.coverpages.org/XRI-FAQ01-20040120b.pdf and in its wikipedia entry
http://en.wikipedia.org/wiki/XRI

----------------------------------------------
From the FAQ:

What features do XRIs have that URIs don't?
The primary distinguishing features of XRIs are:
	* XRIs are "location-independent" - the content of an XRI is
decoupled from the network location
	  of any data or services associated with the XRI.....
  	* XRIs can assert "persistence" of parts of the identifier.....'
	* XRIs provide the ability to "contain" other URIs or XRIs in the
form of cross-references....
	* XRIs allow unlimited delegation of namespaces.....
	* XRIs are built from the ground up to use Unicode for
internationalization.....

And 

How is XRI syntax different from HTTP URI syntax?
For the most part, XRI syntax is a superset of HTTP URI syntax, and most HTTP
URIs can be converted
to XRIs simply by changing the scheme from "http" to "xri."

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THE RELATION OF XRI TO URI

The document XRI Transformations:
http://www.oasis-open.org/committees/download.php/15376#_Toc117301854 shows
how one would transform between XRI's and other URI formats. 

Because of the non-normative examples in there I was under the impression
that not all URIs would automatically function as XRI's and vice versa.
However I remember last year when I stopped following XRI closely that there
was a discussion about trying to make XRIs and URIs 100% compatible. Drummond
Reed seems to imply they are in his message, and the same implication is in
the wikipedia entry when it says "URI- and IRI-compatibility - XRIs can be
used wherever URIs or IRIs are called for. "

So I think it might be good to ask for clarification on this point.

XRI has a sibling project XDI
http://www.oasis-open.org/committees/tc_home.php?wg_abbrev=xdi "The purpose
of the XDI TC is to define a generalized, extensible service for sharing,
linking, and synchronizing data over the Internet and other data networks
using XML documents and XRIs (Extensible Resource Identifiers)" I believe XDI
has defined XML Schemas in which an XRI datatype is found, so it should be
possible to use this datatype in our schemas if it is decided to use XRI. 

Probably we could ask for clarification on this also, is there an XML Schema
datatype for representing an XRI that we can use.

There following is a blog entry on XRI resolution that clarifies some of the
details http://netmesh.info/jernst/Technical/xri-resolution-insights.html


The chairs of XRI Drummond Reed and Gabe Wachob blog at the following
respectively http://www.equalsdrummond.name/
http://blog.wachob.com/


Cheers,
Bryan Rasmussen