Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!mnetor!seismo!ut-sally!husc6!panda!genrad!decvax!tektronix!tekgen!tektools!richl
From: richl@tektools.UUCP (Rick Lindsley)
Newsgroups: net.mail
Subject: Re: Domains: Multiple names OK? (Really, are domains good)
Message-ID: <1558@tektools.UUCP>
Date: Wed, 17-Sep-86 14:06:26 EDT
Article-I.D.: tektools.1558
Posted: Wed Sep 17 14:06:26 1986
Date-Received: Sat, 20-Sep-86 01:01:31 EDT
References: <566@mecc.UUCP> <2502@cbosgd.UUCP> <3920@ut-ngp.UUCP> <3044@columbia.UUCP> <3437@umcp-cs.UUCP>
Reply-To: richl@tektools.UUCP (Rick Lindsley)
Organization: Tektronix, Inc., Beaverton, OR.
Lines: 45

In article <3437@umcp-cs.UUCP> israel@umcp-cs.UUCP (Bruce Israel) writes:
> 
> My point is that you don't require extra complexity from users unless
> it's necessary.  If there is only one SEISMO, then mail person@SEISMO
> should translate out to person@SEISMO.CSS.GOV.  If there are more,
> then mail to that address should return an ambiguous address message,
> so that the user could more completely specify the address.

What do you do in boundary conditions? Like, say there is only one seismo
now, but next week seismo.com springs into life. What do you do with the
users who complain "well, 'user@seismo' USED to work fine". You tell them
that you need more specificity now. They tell you that 99% of their mail
goes to seismo.css.gov; why not make the 1% of the other mail have to do
all that nasty extra typing, and make "seismo" an alias for
"seismo.css.gov"?

Don't laugh; it's happened here.

> Case in point: The University of Maryland mail system.
> 
> I have it set up to work as follows:
> 
> [ ... ]
> 
> 'mail person@arpa-site' will go to the arpanet site.
> 
> 'mail person@uucpsite' will expand uucpsite to the pathalias route,
> and go via that route.

Aha. So what do you do with "vortex"? Does it go via arpa because that is
first in your hierarchy? Sensible, but what do you do when you are used
to sending to user@foovax, a uucp site, and suddenly an arpa site called
foovax appears. Do you issue an error message? Do you know require the
folks to say foovax.uucp? Either way, the behavior has changed, and the
users complain.

My response has been to push domaining whenever possible, and warning that
while user@site is resolved in a certain order as a courtesy, that
user@site 's interpretation is subject to change. If you want to be SURE,
use user@site.domain, or if domain is UUCP, then use a specific a!b!c!user.
We also offer a "pathto" program which searches these things in the indicated
order so you can tell when default interpretations have changed.

Rick Lindsley
co-Postmaster @ tektronix