Date: Wed, 15 Dec 93 11:28:10 +0100
From: Tim Berners-Lee <timbl@www3.cern.ch>
Message-Id: <9312151028.AA04472@www3.cern.ch>
To: Larry Masinter <masinter@parc.xerox.com>
Subject: Re: URN functionality from URLs
Larry,
> a) Hostnames not only get deleted in DNS, they also get reused by
> parties that have nothing to do with the original owners of the
> hostname. That's the main reason not to use them in URNs, and hasn't
> yet been addressed.
That is conventional use. The convention with IX records
would be that reuse would be illegal. We don't have to
change the DNS protocol -- we jsut rule the convention.
> b) If we're considering this kind of naming scheme for URNs, why do we
> want to turn them around?
>
> Why not just say URN:1234.rfc.nic.ddn.mil?
(I find my egg tastes the same whichever end I open it :-)
The / (unlike .) curerntly has a significance of hierarchy
which allows relative URIs which some find useful.
> c) if the DNS 'works' for host names, why not replicate it rather than
> overload it? Can we use DNS protocols without using the existing DNS
> servers? Yes, every machine how has to know it's URL server instead of
> its DNS server, so we've added more configuration. But, you know, DNS
> might be replaced on a different time scale than you want URN->URL
> location service to be supplanted. Tying the two services together
> seems like senselessly making trouble.
On the other hand, do we want to have a sepaarte administrative
system for the domains? Suppose we had a duplicate tree for MX
records... ugh. I feel that it would be so confusing to
have several trees.
It is for the same reason that I prefer the idea of IX record
(impossible to put in, I am sure) to a .ix tree, as I would
have to make a
parc.xerox.com.ix
for every
parc.xerox.com
((I guess one saving grace might be we could fix it to be
parc.xerox.com.us.ix ! ;-))
I guess I am sold on the idea of one information space
containing many sorts of object, rather than a watertight
space for each sort of object.
> Anyway, the DNS people won't let you use DNS for anything like this,
> so you might as well stop dreaming, even though it might work.
I bet they didn't let Carl set up FAX records either...
{
Hey, I tell you what. We set up a parallel domain system like you
say. Keep out of DNS people's hair. We can put mirror the DNS
stuff anyway if we want to. So the new system includes both.
They use the same protocol, different port. Same resolve.conf file,
different filename. If we *really* want to keep out of their hair,
we change the protocol slightly! Prevent any accidental connections
between the two by complementing bit 7 in all bytes!
It's all coming togther now... posterity will love us for this!
\end heavy sarcasm}
No but seriously...
Tim