In theory that isn't much of a problem. In fact you could even keep SMTP for the transport and RFC822 for the message format. Only accept incomming SMTP from hosts/networks you trust and/or have some kind of formal agreement with. X.400 did roughly (exactly) that, although it used a different transport. Ever heard of X.400 Spam :-)? In practice it's of course less simple, since you will miss the baby that went out with the water. And, noone will be prepared to pay the cost of sending mail through such a regulated system. As is, we pay via the time spent with the <Delete> button. Sorry, no free lunch. Gunnar Lindberg >From ietf-bounces@xxxxxxxx Thu Aug 16 00:13:07 2007 >In-Reply-To: <46C36599.9040907@xxxxxxxxx> >References: <198A730C2044DE4A96749D13E167AD3701341995@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> <8244E3BE-1A26-4B0A-99DC-0DF7AF7F8810@xxxxxxxxx> <46C29647.5070202@xxxxxxxxxxxx> <FABD8E3A-D5CF-4EED-927B-A039BCAEE90C@xxxxxxxxx> > <46C36461.2060907@xxxxxxxxxx> <46C36599.9040907@xxxxxxxxx> >Message-Id: <16091B83-0AB3-41A5-A6E4-D8868B61FA30@xxxxxxxxx> >From: Iljitsch van Beijnum <iljitsch@xxxxxxxxx> >Date: Thu, 16 Aug 2007 00:11:13 +0200 >To: Michael Thomas <mat@xxxxxxxxx> >Cc: John Kristoff <jtk@xxxxxxxxxxxxxxxx>, Keith Moore <moore@xxxxxxxxxx>, > Fred Baker <fred@xxxxxxxxx>, ietf@xxxxxxxx >Subject: Re: e2e >On 15-aug-2007, at 22:44, Michael Thomas wrote: >> Robust for what? Spammers? The simple fact of the matter is that the >> alternative is to just shut down port 25 given the growth in both >> volume >> and complexity to filter. That ain't robust either. Dealing with >> false >> positives is the cost of doing business on the internet these days. >> Welcome >> to reality. >That means giving up on email because it's not useful if it's not >very close to universal. >If only there were a standards organization that could design a >messaging protocol that can work across the internet... _______________________________________________ Ietf@xxxxxxxx https://www1.ietf.org/mailman/listinfo/ietf