Path: utzoo!utgpu!water!watmath!clyde!cbosgd!osu-cis!tut!tut.cis.ohio-state.edu!triceratops!karl
From: karl@triceratops.cis.ohio-state.edu (Karl Kleinpaste)
Newsgroups: comp.mail.uucp
Subject: Re: Duplicate site names
Message-ID: <3858@tut.cis.ohio-state.edu>
Date: 5 Jan 88 17:15:26 GMT
References: <271@ontenv.UUCP> <7905@g.ms.uky.edu> <44208@beno.seismo.CSS.GOV> <22341@hi.unm.edu> <446@minya.UUCP>
Sender: news@tut.cis.ohio-state.edu
Lines: 44
In-reply-to: jc@minya.UUCP's message of 5 Jan 88 03:21:27 GMT

jc@minya.UUCP writes:
   Sorry, but you haven't been listening to the complaints from the users of
   the various "tut" machines, some of which are properly hidden behind some
   domainized gateways.

No, he's been listening just fine.  We've got one of those Tuts, and
it's in a domain hidden properly behind a gateway.

   The basic scenario is that someone at Fubar University has their tut.edu 
   down the line from fu.edu; I send them mail to ...!fu.edu!tut.edu!jrh;
   the mailer at ... realizes there's a faster route to tut.edu than via
   fu.edu and mails it to tut.edu over in Finland.

The whole point is that the names fu.edu and tut.edu are inherently
unique.  They're defined to be unique.  They can't *not* be unique.
There is only one tut.edu anywhere, and only one fu.edu.

Now, actually, the names in question are things like tut.colorado.edu,
tut.rochester.edu, tut.cis.ohio-state.edu, and tut.fi.  Those are
unique names.  No one can conflict with our tut.cis.ohio-state.edu,
because they have no means by which to interfere with our management
of the .cis.ohio-state.edu domain.  There could even be a
tut.ohio-state.edu along with our tut.cis.ohio-state.edu and there
would be no problem - the domain specs force them to be unique.

   Proper domainizing doesn't help a bit here.  The real culprit is the
   assumption of unique names.  This was a reasonable assumption back when
   we had only a few thousand nodes to worry about.  It is doesn't work
   so well as the number of nodes approaches 6 digits.

It works just dandy if you'll bother to include a full domain spec.
The problem is solved, it just has to be implemented.  I don't care if
the number of hosts passes 2^32 - a domain spec forces uniqueness in
every case.

The problem arises when somebody decides that his host is "smart" in
some sense, and obliterates either [a] the required !-path context, or
[b] the required domain spec context.  With either context in place,
the names are unique.  Take away the context, and you have conflict.
This is why tut.cis.ohio-state.edu and tut.fi have had problems.  Just
stop taking away the context, and anyone wanting to reach any Tut will
find exactly what they're looking for.
-=-
Karl