Overloaded URIs must GO!

Paul Prescod paul at prescod.net
Fri May 28 19:36:07 BST 1999

David Megginson wrote:
> 1. URNs don't really exist, or at least, last I checked, there was no
>    authoritative specification of the different URN schemes (without
>    which URNs are worthless).  URNs have been under development for
>    most of the 1990s with few tangible results, and I'm growing
>    slightly skeptical.

When we had the namespaces discussion, I said that using URIs was a bad
idea because URNs don't exist yet so everyone could only use URLs. I
pointed out then that using URLs is bad and probably

I was told, however, that URNs DO exist. Anything that conforms to the URN
syntax is a URN. I wasn't especially thrilled with this syntax-centric
definition but there was no other definition of a URN and in the rather
loosely formalized world of the Web what more could I expect? So I wasn't
happy with the loose definition of URNs but I accepted that they exist.

I see today, however, that we have a new document that clears up my

It says:

"Not all syntactically correct URN namespaces (per the URN
syntax definition)  are valid URN namespaces.  A URN namespace
must have a recognized definition in order to be valid."


It also gives a mechanism for defining new URNs. Furthermore, last month a
URN namespace was actually proposed as an Internet Draft:


So now I think it can truly be said that URNs *exist* and can be used. Of
course in the general case resolution could be a big problem but in the
specific case of XML namespaces it is not.

It is now both legal and appropriate for us to propose the hname:
namespace which is defined to mirror the HTTP namespace (in terms of
ownership and uniqueness) but be a URN instead of a URL and thus
explicitly unretrievable. In the meantime, it seems that we can use an
experimental namespace: "x-hname" and take our chances that nobody
somewhere else on the Web will use the same name incompatibly.

 Paul Prescod  - ISOGEN Consulting Engineer speaking for only himself

Alabama's constitution is 100 years old, 300 pages long and has more than
600 amendments. Highlights include "Amendment 393: Amendment of Amendment
No.  351", "Validation of Laws Regulating Court Costs in Randolph County",
"Miscegenation laws", "Bingo Games in Russell County", "Suppression
of dueling".  - http://www.legislature.state.al.us/ALISHome.html

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