Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!henry
From: henry@utzoo.UUCP (Henry Spencer)
Newsgroups: net.mail
Subject: Re: Area-code as uucp domains
Message-ID: <3513@utzoo.UUCP>
Date: Fri, 3-Feb-84 16:01:45 EST
Article-I.D.: utzoo.3513
Posted: Fri Feb  3 16:01:45 1984
Date-Received: Fri, 3-Feb-84 16:01:45 EST
References: <426@psuvax.UUCP>, <758@ulysses.UUCP>, <3508@utzoo.UUCP>
Organization: U of Toronto Zoology
Lines: 23

Laura has made the same mistake as a lot of other people when they see
domains for the first time:  they confuse names with routing.  Our
full domain-based name might be, say, utzoo.ec.uucp (ec being Eastern
Canada).  But if watmath.ec.uucp sends mail to utcsrgv.ec.uucp, this
doesn't mean that the mail has to pass through the "top" site of the
ec domain.  In fact, in this case the mail goes direct.  Only if the
sending site has no idea of a route to the destination does it consult
the "top" site.  Even this does not necessarily imply sending the mail
via the top site -- the sending site may simply ask the top site for
enough information about the destination to construct a path (note
careful wording:  the top site doesn't necessarily have to supply a
path, just help the sender to figure one out).

With the old uucp stuff, naming and routing are inextricably coupled.
In fact, names have only a local significance, since it's the route
you specify:  "...!foobar!vortex!lauren" is unambiguous even though
there are two "vortex" sites, because the individual names matter only
to the sites that immediately precede and follow them in the route.
The domain-based system decouples naming and routing almost completely,
and it is important to make the distinction.
-- 
				Henry Spencer @ U of Toronto Zoology
				{allegra,ihnp4,linus,decvax}!utzoo!henry