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Path: utzoo!watmath!clyde!bonnie!akgua!whuxlm!whuxl!houxm!vax135!petsd!peora!jer
From: jer@peora.UUCP (J. Eric Roskos)
Newsgroups: net.mail
Subject: Re: More thoughts on mail relays
Message-ID: <1746@peora.UUCP>
Date: Sat, 26-Oct-85 18:52:23 EST
Article-I.D.: peora.1746
Posted: Sat Oct 26 18:52:23 1985
Date-Received: Mon, 28-Oct-85 03:26:48 EST
References: <1813@umcp-cs.UUCP>
Organization: Perkin-Elmer SDC, Orlando, Fl.
Lines: 121

I see that in the 2 weeks that I've been off converting MH.5 to run under
System V (and our site has been converting itself to System V, for that
matter), despite my exhortation that people not followup on my article
with reiterations of things said in the past, people have continued to
repost the same ancient, tired arguments.  Except those who have decided
to resort to ad hominems by claiming I don't know the definition of AI
(I used to work for an AI software company, so naturally I am hopelessly
out of touch with what academia feels is the definition, regardless of
what people who have just encountered me may think of my position in that
regard (-:).

We have seen reiterated the statement that routing strings with "@" in
them are "dangerous" (the point at which Mark Horton and I reached an
impasse on this debate by mail, incidentally) because they are
"ambiguous".  In fact, that seems to be the "jist" of all the counter-
arguments regurgitated.  We have also seen disconnected statements that
say "!-precedence is preferable in the UUCP network" and then go on to
assert, without intervening premises, that therefore "@" in a routing
string should be "declared invalid".

I've only seen one marginally close counterargument, and that is the one
that argues that @ should be given precedence for "consistency".  Well,
that is fine in the theoretical world, but not in reality; as I have
pointed out to some of you who have recently sent me mail, RFC822 does not
require consistency, however, for the message envelope, and the attempts
to force consistency retroactively on the UUCP network are what I am claiming
is itself dangerous.

Now, for those of you who insist on making their arguments by quoting Mr.
Rogers or popular comedians, let me point out that the last clause on the
above sentence is a proposition which I am about to informally demonstrate.

Prior to the introduction of software which was intended to integrate the
networks, the character "@" had no significance as a distinct token in the
UUCP routing language.  [An aside for the stubborn: the UUCP routing language
is the language in those files named "D.mysiteX123AB", or
"X.mysite1234AB", in the UUCP queues.  It has nothing to do with the plain
D. files containing the messages which, except for routing stamps at the
front, most of us (including me) agree should be RFC822-compliant.]
Therefore, one would send mail destined for a "gateway" through using
the "!" syntax, with a destination mailbox name looking something like
"joe@bigvax.ARPA".  Now, if your average UUCP site tried to send to a
mailbox with that name, it would go looking for a user in /etc/passwd with
that name, wouldn't find one, and would reject the address as erroneous.
However, some sites, the gateways, were smarter, and would treat it as an
address on another network, which they would send it to.

Then someone produced a product which they introduced into a software
distribution, which was intended to help these gateway sites.  But it was
distributed to everyone, and soon many people installed it, whether they
needed it or not.  And furthermore, AND THIS HAS BEEN MY POINT, they in-
stalled it in violation of what has come recently to be called Lauren's
rule, because an arbitrary site out there, say mine, whose users had
been trained to use the old syntax, couldn't any more, because suddenly
that site was *no longer accepting the syntax that had formerly been in use*.
It was accepting a *new language* entirely.

Recent arguments have overlooked this; in typical self-centered fashion,
they say instead "now that I've installed @-precedence transport agents
here, *that* will be the standard; all the old sites just accidentally
didn't know about @, and they are wrong."

In fact, however, standard AT&T Unix mail still does not give @-precedence.
It probably won't do so until AT&T either adopts Sendmail, or Smail, or
another of the new smart mailers.

Ironically, I guess, I am *not* making my argument from a similar
position, since our mailer here can handle either syntax, simultaneously,
and in fact presently does: it uses "@" when going through mailers at
certain industrial sites which don't recognize the new syntax, and uses
"!" when going through some of the newer sites, particularly Seismo.
(Presently it can't do this when using the probabilistic gateway selection
scheme for distributed nameservers, but that is a present limitation, not
a feature.)

The real problem here, I've recently come to conclude, is a psychological
one.  Sendmail is so difficult to reconfigure that now that most sites have
some semblance of a working sendmail.cf file, everyone is in grave terror
of ever having to change it.  And, ironically too, the approach I have
been proposing would not require changing any sendmail.cf files!  It would
require sites that are currently in violation of Lauren's rule replace
their sendmail-invoking rmail with a slightly "smarter" rmail that didn't
give @-precedence, voluntarily, if they wanted to comply.  And, even yet
more ironically, the UUCP Project is about to release just such a product,
which could provide just that facility; but instead it provides @-precedence.

Actually it's true that this has become a "religious debate".  My site can
handle either syntax, in compliance with the original UUCP routing
language; sites that install smail will handle it just fine, as will
Sendmail sites.  The only ones that won't are the ones with "dumb mailers,"
such as mailx or plain Unix mail, where the users will suddenly have to
be instructed to write their routing strings slightly differently, or edit
their alias files if they have them.

Well, my religion says you should be kind to people, and my argument is
largely one from kindness and upward-compatibility.

That's all I have to say on the matter, then.  Maybe I should end with an
ad hominem!  But no, this is a "religious" debate, so I will turn the
other cheek and all that.

It is a sad thing, though, that I have seen so little logic (in the form
of extended argument) and so much regurgitation of simple facts and
superstitions.  Also that the supporters all write by *mail*, while the
ad-hominem detractors post news messages!

So maybe I can get back to work now... and if users at dumb-mailer sites
grumble and complain, I could always smugly say "GO NEM!"  I guess upward
compatibility is our middle name (not "who" :-)).
-----------
Disclaimer: The above does not necessarily reflect the opinion of the
Perkin-Elmer Corporation.  Furthermore, I am not involved in the implem-
entation of present Perkin-Elmer mail products.

NEM is a trademark of the Perkin-Elmer Corporation.
-- 
Shyy-Anzr:  J. Eric Roskos
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