Re: [URN] draft-ietf-urn-nid-req-01.txt

Dan Connolly (
Fri, 28 Mar 1997 03:13:22 -0600

From: Dan Connolly <>
Subject: Re: [URN] I-D ACTION:draft-ietf-urn-naptr-04.txt
Date: Fri, 28 Mar 1997 03:01:27 -0600
Message-Id: <>
To: wrote:
>        Title     : Resolution of Uniform Resource Identifiers using the
>                    Domain Name System
>        Author(s) : R. Daniel, M. Mealling
>        Filename  : draft-ietf-urn-naptr-04.txt
>        Pages     : 14
>        Date      : 03/21/1997

This NAPTR stuff is cool: it's an interesting point in
the design space between the old path: scheme and MX

A few comments:

>In conjunction
>with a long TTL for * records, the average number of probes to
>DNS for resolving DUNS URNs would approach one.

I would very much like to see the full argument behind that
sentence -- it appeals to my intuition, but I want to
study the details. Are they available somewhere?

>      sprintf(key, "", extractNS(URN));

er... where's the specificaiton of extractNS? That seems
absolutely critical to the whole thing, and yet I don't
see it specified anywhere except the three examples
(which I assume are non-normative, per standards tradition).

Based on the examples, the algorithm seems to be
"grab the stuff before the :; if it's urn:,
grab everything up to the _next_ :."

Why the special case for the urn: prefix? I seem to
be asking that a lot. But I'm just applying occam's
razor: unless there's a darn good reason for special-casing urn:,
we should not.

Hmm... whoever administers seems to be able
to introduce new URL schemes at will. That should
certainly be discussed in the URL process document!

I thought I
saw a document specifying the policies for,
but I can't seem to find it now.

Dan Connolly, W3C Architecture Domain Lead
<> +1 512 310-2971
PGP:EDF8 A8E4 F3BB 0F3C FD1B 7BE0 716C FF21
Message-Id: <>
Date: Fri, 28 Mar 1997 03:13:22 -0600
From: Dan Connolly <>
To: Patrik Faltstrom <>
Subject: Re: [URN] draft-ietf-urn-nid-req-01.txt

Patrik Faltstrom wrote:

> > Is it really necessary/useful to go through this exercise twice?
> A namespace is definitely not the same thing as a URL scheme. Two
> different things, but the _process_ can be similar, just like the
> processes defined for MIME-types.

Hmm... argument by assertion. I can play that game too:
A namespace definitely IS the same thing as a URL scheme.

I don't have any logical argument, but I can cite the
intent of the designer of URLs:

TimBL, circa 1990

The WWW scheme uses a prefix to give the addressing sub-scheme, and
then a syntax dependent on the prefix used, in order to be open to any
new naming systems. 

See also, RFC1630 (informational) and TimBL's more recent writings:
including a very intersting and relavent bit
about "Naming: A social and contracual Issue."

As a trump card, I'll play occam's razor, which places
the burden on you to show that they're different.

Dan Connolly, W3C Architecture Domain Lead
<> +1 512 310-2971
PGP:EDF8 A8E4 F3BB 0F3C FD1B 7BE0 716C FF21