Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.3 4.3bsd-beta 6/6/85; site well.UUCP
Path: utzoo!watmath!clyde!burl!ulysses!bellcore!decvax!decwrl!amdcad!lll-crg!well!ulmo
From: ulmo@well.UUCP (Brad Allen)
Newsgroups: net.mail
Subject: Re: Parsing mixed form addresses (! and @)
Message-ID: <592@well.UUCP>
Date: Sun, 2-Feb-86 20:25:26 EST
Article-I.D.: well.592
Posted: Sun Feb  2 20:25:26 1986
Date-Received: Tue, 4-Feb-86 03:28:39 EST
References: <1942@peora.UUCP> <11500004@unido.UUCP> <117@sering.mcvax.UUCP>
Reply-To: ulmo@well.UUCP (Brad Allen)
Organization: Whole Earth Lectronic Link, Sausalito CA
Lines: 41

>One of the big problems facing unix mail system now is the ambiguous
>nature of "mixed form addresses", e.g. x!y@z.  As was recently mentioned
>by some others, the key to correctly parsing these addresses is to
>know the source.  If you know the source (or more correctly its
>addressing format), then you can almost always determine the correct
>meaning of the address.  UUCP addresses should be assumed to have
>! precedence.  Expect that when you generate them, and accept it
>when you receive them.  Mail from 822 standards sources (PhoneNet,
>SMTP, Bitnet, ...) should be given %/@ precedence.  This the basic
>policy being adopted in Europe.

The way I have been sending mail through mixed standards is supposing
that each machine just looks at the spot it wants to.  That is,
if a machine is ARPA, then it will look to the right, and if
it's UUCP, it will look to the left.

This makes thing ambiguous since some machines have more than
one network operating, but I make sure I specify what network
I'm sending to, and this makes it unambiguous.

I think I once sent successfully through this path:

ptsfa!ucbvax.ARPA!ucscl!firezar@ucscc.UUCP

This goes (from my machine well) to ptsfa via UUCP (the Well
tends to assume uucp addresses), and then to ucbvax (via uucp).
Then ucbvax switches over to the ARPA format, looks at the end
of the address, and sends to ucscc.UUCP (which I suppose
gets converted right over to the uucp send program on ucbvax ...!)
then ucscc sends to ucscl!firezar as if it were uucp address.
ucscc assumes the ! or : format, unless I specify a network
like .arpa or .bitnet or .UCSC.

Until every machine in the whole universe knows of every
other machine (!!!, someday ...), and even when we get
to that point, I strongly beleive in the "view it in context"
argument.

		..ucbvax!{ptsfa,dual,lll-crg}!well!ulmo
		..ucbvax!ucscc!ucscl!firezar (specify to Ulmo)
		Brad Allen