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Path: utzoo!watmath!clyde!cbosgd!ihnp4!plus5!hokey
From: hokey@plus5.UUCP (Hokey)
Newsgroups: net.mail.headers
Subject: Re: Is there a standard format for cross-domain addresses?
Message-ID: <780@plus5.UUCP>
Date: Tue, 25-Jun-85 13:23:59 EDT
Article-I.D.: plus5.780
Posted: Tue Jun 25 13:23:59 1985
Date-Received: Wed, 26-Jun-85 07:10:58 EDT
References: <592@deepthot.UUCP>
Reply-To: hokey@plus5.UUCP (Hokey)
Organization: Plus Five Computer Services, St. Louis, MO
Lines: 30

In general, one should provide as little routing information as possible.
This implies that one should send mail to an address (rather than a route).
This also implies that the net gateways should be responsible for altering
the headers and/or routing information as they see fit (again, this should
be kept to a minimum).

This is not often easy.  It requires knowing where the "closest" smart mailer
is.  (If any word is wrong at the end of a sentence, a linking verb is.)

It is dangerous to use hybrid (mixed ! and @) routes in UUCP land, as there
is no consistent precedence associated with the network operators.  This is
not true for RFC822 header fields, but hybrids are dangerous here as well,
because many sendmail sites still prepend their site name in the From: lines.
A fix to this problem has been posted, but not very many sites seem to have
installed it.

From UUCP land, gateways should be able to accept mail sent to dom.ain!user
(e.g.: site.arpa!user, or site.att.uucp!user).  I know that the DEC Engineering
Net gateways accept this form, and I know several Arpa gateways do as well.
These Arpa gateways also accept mail to site.csnet!user (no csnet-relay is
needed).  I do not know about the BITNET gateways.

There are, of course, people who disagree with what I say.

In any event, expect all hell to break loose on 15 July, when the Internet
converts from .arpa to .{edu,com,gov,mil,oth} stuff, and isolates the domain
name from the transport mechanism.
-- 
Hokey           ..ihnp4!plus5!hokey
		  314-725-9492