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On Wednesday 19 March 2003 22:20, Jeff Lowery wrote:

> The same can be said of URLs, which are unregistered, and collisions could
> foreseeably happen in domains that are very large. Should every domain
> holder establish a local registry?

But you're supposed to only use URLs you control.

YES, you could start emitting documents with namespaces starting 
http://www.alaric-snell.com/... just to annoy me. But that holds for any 
naming scheme, central registry or not.

The idea with the use of HTTP URLs as unique IDs is that *the DNS* is the 
central registry.

So apart from through incompetence or deliberate misuse, there will be no 
colission with HTTP URLs.

However, I don't think URLs should be used as namespace URIs at all. It opens 
up cans of semantic worms, as we have seen. I reckon namespaces should have 
been restricted to being URNs alone, but weren't because most people don't 
know how to get hold of URNs. Using URLs for namespaces was a quick hack to 
avoid having to go to the effort of making it easier to get URNs, and the 
price is being paid with user confusion and flamewars about what namespace 
URLs should resolve to.

http://www.iana.org/assignments/urn-namespaces

...making a URN namespace that looks like:

urn:domain:alaric-snell.com:wibble

...would make sense IMHO; the rules being that the owner of a domain in DNS 
can generate URNs as she sees fit that follow the rule

"urn:domain:<domain name>:<their choice of identifier>". This would allow 
them to delegate arbitrary sub-registries within their organisation by using 
subdomains, as well as imposing whatever structure they like (possibly 
hierarchial) on the identifier part. That would leverage the existing domain 
registry to make it possible for every domain name holder to make up as many 
URNs as they like.

To cater for people who lack domain names, a URN merchant could sell the 
service of ensure uniqueness of:

urn:domain:urns-r-us.com:<customer id>:<customer's choice of stuff>

ABS

-- 
A city is like a large, complex, rabbit
 - ARP

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