Kingsley Idehen wrote:
On 6/28/09 6:33 PM, "Tom Heath" <[email protected]> wrote:
Hi Richard,
2009/6/25 Richard Cyganiak <[email protected]>:
<snip/>
(On the value of content negotiation in general: I think the key point is
that any linked data URI intended for re-use, when put into a browser by the
average person interested in linked data publishing, MUST return something
human-readable. That's a hard requirement, otherwise people will never be
confident about what a particular URI means and hence they won't re-use.
That was the thinking behind the Cool URIs note when Leo and I wrote it a
few years ago. In the past, the only way to get that effect was with content
negotiation, so even though content negotiation is a pain, it's what we had
to do. In the present, we have an alternative thanks to RDFa.
Not disagreeing at all about the human readable requirement, but just
a question... in this scenario you describe, is there not a risk that
Joe User will enter that URI and come to the conclusion that it
identifies the document (or section thereof), rather than a thing
described in the document?
Interested in your thoughts :)
Tom.
Tom,
Of course not, if dealing with an HTTP URI deployed in line with the Linked
Data meme's deployment guidelines. In short, the user will encounter a
document describing the Thing identified by the URI.
The issue is not the document, but what it represents (metadata) and how it
comes to be associated (implicitly) with the entity (resource) it describes
via the entities URI.
When all is said and done, the Linked Data meme has simply used HTTP to fix
an age old problem: implicit association of an Entity with its Metadata
within the context of distributed computing without any platform lock-in.
Rewind back to pre. Web, then ask yourself: how did programmers refer to
data objects and de-reference their representations (typically a proprietary
language and platform specific data structure).
Again, Linked Data is just about making what was platform specific, platform
independent, via HTTP i.e., "data access by reference" and "data
manipulation by values exposed by de-dereferenced data structures".
We really need to keep this quite simple. There are zillions of people that
understand "data access by reference" etc.. They also understand Metadata
etc.. What they don't understand is how we sometimes *inadvertently* make
this whole Linekd Data meme thing complex by not connecting the meme to what
existed before the Web (which was actually created on a computer that
already had a fully functional distributed object based OS etc..).
Kingsley
Tom,
Much short version.
If a user "Joe Web User" becomes fixated on the metadata document URI we
don't have a problem. I say this because the aforementioned document
will always act as a conduit to the URI of the entity it describes.
Thus, Linked Data aware user agents will always be able to figure this
out and get what they want.
The most important thing is that we add the metadata document to the
general mix on the Web. By this I mean: in addition to the basic HTML
document (which has no specificity re. metadata) and the standard
ability to lookup markup (via browsers for instance), we now have the
ability to lookup a metadata bearing document via a URI.
Keeping the URIs within scope of user agents is the single most
important thing, since doing this is what really makes the Linked Data
meme tick :-)
--
Regards,
Kingsley Idehen Weblog: http://www.openlinksw.com/blog/~kidehen
President & CEO
OpenLink Software Web: http://www.openlinksw.com
