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From: MRC@SU-SCORE.ARPA (Mark Crispin)
Newsgroups: net.mail.headers
Subject: Re: smtp, errors and delivery
Message-ID: <368@hou3c.UUCP>
Date: Mon, 5-Mar-84 16:23:51 EST
Article-I.D.: hou3c.368
Posted: Mon Mar  5 16:23:51 1984
Date-Received: Wed, 7-Mar-84 07:38:57 EST
Sender: ka@hou3c.UUCP (Kenneth Almquist)
Lines: 20
To: Rudy.Nedved@CMU-CS-A.ARPA
Cc: Header-People@MIT-MC.ARPA
In-Reply-To: Message from "Rudy.Nedved@CMU-CS-A" of Mon 5 Mar 84 11:16:00-PST
Postal-Address: 725 Mariposa Ave. #103; Mountain View, CA 94041
Phone: (415) 497-1407 (Stanford); (415) 968-1052 (residence)

Rudy -

     The problem is that it is a "de facto standard" to reject
MAIL FROM: commands for the slightest bogosity (even if the
bogon turns out to be at the SMTP server's end!).  A number of
SMTP servers reject a-d-l's, for example.  Still others reject
mail from "unknown hosts" when the problem is that the SMTP
server's host table is out of date.  Yet another problem is
that many (most?) SMTP servers reject bracketed host names.
There are a number of "nameless" TOPS-20s which talk TCP/IP
and use their bracketed address forms as a name (e.g. [1.2.3.4]).
This is valid according to the standard and TOPS-20 fully
implements it, but try convincing a large number of SMTP
servers of that!!

     I won't even go into the details of how to reply or return
messages in these cases (other than "implement the standard").

-- Mark --
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