> Spammers use an openrelay SMTP server to post thru. Let's call that > machine A. They make their headers appear to be from elsewhere. Let's > say that is machine B (it might be real or not). When the mail arrives > at machine C (it's desination), that mail server can see evidence of B > (clearly), but also information pertaining to A? Or is it that only > information from some uplink A connects to is evident?
C should append a line a bit like: "received by C[123.123.123.123] from A[432.432.432.432] at 00:00 GMT +0000" > > If C sends a digest (subject of a new RFC) to B of the message through > SMTP saying "did you send this?", then there are two possibilities - (1) > The answer is "no I did not", or (2) no such mail server. Does A have > record of the email? pretty much not, once its sent or bounced the MTA is glad to get rid and reclaim the space. > If it does, can it determine that it was from the > real email user? Possibly yes depending how tightly it is set up itself to prevent relaying, more likely no, if A has faked a message from a real user of B it would be hard to differentiate from a bona fide one. > Does this cover all the bases? > > Hmmm, I have half a feeling that this has been explained to me > already..... > > Regards, -- To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> For additional commands, e-mail: <mailto:[EMAIL PROTECTED]>
