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Posting-Version: version B 2.10.1 6/24/83; site hou3c.UUCP
Path: utzoo!watmath!clyde!burl!hou3c!dpk@brl-vgr.ARPA
From: dpk@brl-vgr.ARPA (Doug Kingston)
Newsgroups: net.mail.headers
Subject: Re:  smtp, errors and delivery
Message-ID: <372@hou3c.UUCP>
Date: Mon, 5-Mar-84 23:07:22 EST
Article-I.D.: hou3c.372
Posted: Mon Mar  5 23:07:22 1984
Date-Received: Wed, 7-Mar-84 07:39:56 EST
Sender: ka@hou3c.UUCP (Kenneth Almquist)
Lines: 19
To: don.provan@cmu-cs-a
Cc: Rudy.Nedved@cmu-cs-a, Mark Crispin , Header-People@mit-mc


	There are two different philosophies being used here.  One says
"Deliver the message at all costs", while the other says "Make a reliable
deliver, or return it".  The first is the method used by people that
will give you a null return addresss (MAIL FROM:<>) while the second is
the more conservative stratagy and gives you a better guarantee that you
will know that the message was delivered (or not).  MMDF (the system I
maintain) is a more conservative mailer.  We rigorously adhere to the
transfer of responsibility model and we always give a return address
(even it is the postmaster address).  We do not attempt to supply alternate
MAIL FROM addresses, and as it turns out we now almost never get rejections
based on the MAIL FROM address.  This was not true when the net first
changed protocols though.

	Mark and others are not wrong in what they are doing, it just
shows a difference in priorities.

					Cheers,
						-Doug-