Re: [AOLSERVER] My posts are failing to be uh, posted. (posted directly through listserv and not via email)

[Mark Aufflick]

of course such a solution would can emails from people who use a sendmail queue on their local linux or NT box for outbound, but have their mail (and thus MX records) hosted elsewhere. my home office is setup like that, and i'm sure a lot of small businesses are... so as you point out, spammers could circumvent this, while it would be affecting small users who aren't in a position to have M records pointing at their changing cable ip addresses. Dossy wrote: On 2003.08.26, Chris Davies <[EMAIL PROTECTED]> wrote: The only problem here is that most of the cable modems out there have valid reverse addresses, and providers don't block outbound port 25 connections allowing spam to flow freely from cable modems that have valid reverse lookups. I've been thinking this might be a good way to stop mail header forgeries (which most spam falls into the category of) but would annoy a lot of people ... Upon receipt of mail at the end of the DATA portion of the SMTP transaction, look at the mail envelope (and possibly the From: header) and parse out the domain name that the mail is supposedly sent from. Then, look up the DNS for that domain name, looking for IN MX records. If the machine's IP that is on the remote end of the SMTP transaction isn't one of those machines indicated in the MX record, refuse to accept the mail. -- Mark Aufflick e: [EMAIL PROTECTED] w: www.pumptheory.com (business) w: mark.aufflick.com (personal) p: +61 438 700 647 -- AOLserver - http://www.aolserver.com/ To Remove yourself from this list, simply send an email to <[EMAIL PROTECTED]> with the body of "SIGNOFF AOLSERVER" in the email message. You can leave the Subject: field of your email blank.