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uri, urn and info

From: Eric Hellman <eric@openly.com>
Date: Tue, 7 Oct 2003 17:45:32 -0400
Message-Id: <p06002000bba8c455aba6@[10.0.1.2]>
To: uri@w3.org


urn would be great. but perhaps a concrete example would illustrate 
where info may be coming from:

What single,  stable, and widely used name should I use to refer to 
the text/plain mime type?

It would seem to someone from the outside, perhaps even someone from 
Tim Bray's planet, that it might be a good idea to use something from 
the "urn:" URI scheme.

I asked google what URI to use for a mime type, and, to my great 
surprise, google's response pointed to an e-mail I had sent to the 
rdf-interest mailing list in 1999, and which is still worth reading. 
http://lists.w3.org/Archives/Public/www-rdf-interest/1999Nov/0065.html

At that time, Dan Connolly had suggested the use of 
http://www.isi.edu/in-notes/iana/assignments/media-types/text/html to 
identify text/html
If we dereference this url, I obtain a resource which I quote here IN 
ITS ENTIRETY:
"


See RFC 2854.
"
which of course, is hugely useful to semantic web applications.

A year later, James Tauber (who I doubt is the ignorant dolt that I 
am)  admitted  to not knowing of this URL when the question comes up 
again, and suggests
http://www.iana.org/mime-types/text/plain
which has nothing on the dereference.

Graham Klyne, who is also not an ignorant dolt, suggested that 
"urn:iana:content-type:text/plain" was on the way.

Dan Connolly then pointed to 
ftp://ftp.isi.edu/in-notes/iana/assignments/media-types/"
as the source of authority for these assignments; but if I deference 
and follow that, I get ftp URI's like
ftp://ftp.isi.edu/in-notes/iana/assignments/media-types/text/html
  which appears to result in the same resource that I quoted in its entirety

Looking at actual practice on the web, I see that Dan's advice is 
often ignored. I see all sorts of stuff like 
"urn:mimetype:text/plain". Google finds a total of 297 document which 
use Dan's uri, versus 1900 documents using the ftp.isi.edu version.

looking further, I see that there was an "eastlake" draft that IETF 
seems to have deep-sixed. I learned, tantalizingly, that Graham 
Klyne, Ted Hardie and Michael Mealling did some work to perhaps 
create uris for iana registered stuff, their draft is also expired by 
ietf, so I cannot tell  what they found.

The bottom line is that the at least for this one example, the URI 
infrastructure has failed to provide a single, stable uri for 
text/plain in a way that people know to use it. Nowhere is there a 
place that an authoritative source (other than Dan Connolly, who I 
have never met) says to use a particular uri for text/plain.

let's try again with "the iso 8879 character set". Is there a good 
uri for that? not that I can easily find.
maybe that's not a good one. how about a uri based on the iso country 
code for Mexico? sorry, I can't find one.
ok, how about languages, is there a universally understood URI for 
American English? Someone on the list can tell me maybe, but what 
about all those people who aren't receiving the URI list???

  Developing a common language, which is what we're trying to do for a 
specific, web based application, is a social, non-technical process 
of consensus. URN, and HTTP for that matter, has failed to make that 
consensus happen, even for these "easy" cases. So the result is that 
all sorts of groups make up their own vocabulary and none of the 
groups can talk to one another. Although I think the info draft can 
be improved in many ways, I'd have to say that organizations like 
NISO with experience at developing that kind of consensus in the 
bricks and mortar world need to be actively involved.

I really don't care whether it's urn or info ( or http, for that 
matter). I can make any of them work, if only we could just get on 
with it.

so here's a taxonomy for the ways that I've seen put forward for name- uri's

http
easiest and most functional, but the minter has to spend a lot of 
money and time getting people to adopt the resulting URIs. 
unfortunate car/document argument that always crops up.

tag
even easier to mint, no function other than uniqueness. The minter 
has an even bigger hurdle to get the URI  space adopted, due to 
people's unfamiliarity with tag

urn
rigorous requirements but the real hurdle with urn is to get IETF 
consensus. IETF lapses most URN proposals and doesn't promote or use 
the ones it does.

info
minter has to obtain NISO sign-off. hardly any requirements. no 
function except an unspecified namespace registry.

Eric

-- 

Eric Hellman, President                            Openly Informatics, Inc.
eric@openly.com                                    2 Broad St., 2nd Floor
tel 1-973-509-7800 fax 1-734-468-6216              Bloomfield, NJ 07003
http://www.openly.com/1cate/      1 Click Access To Everything
Received on Tuesday, 7 October 2003 17:45:40 UTC

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