North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: Barracuda Networks Spam Firewall
On Tue, 18 May 2004 16:13:20 EDT, Todd Vierling said: > On Tue, 18 May 2004 [email protected] wrote: > > : Yes, it *would* be nice if everybody in the world was able to DTRT on > : their outward-facing gateway and send back an immediate 550 on a RCPT TO: > : in order to stop stuff right up front. However, this implies getting > : buy-in and resources of all the appropriate people. > > Blocking outbound mail from such entities is a pretty good way to get > buy-in. (Yes, there's a DNSBL in work to enumerate such systems.) When it gets built, will it list AOL.COM for not rejecting at the original RCPT TO? Or Hotmail.com? (Consider the following 2 pieces of mail - mail comes in from someplace with a From: @aol.com, our Listserv tries to process the command (which was actually spam, but it's hard to tell that until you try to handle it), and send the response back... notice that AOL didn't 550 my mail, but accepted and bounced it. Similarly for the hotmail.com mail - the spam comes in, and they accept-and-bounce our response rather than 550 it (although to be fair, they usually DO manage to 550 this stuff). Yes, it's generally a good idea - but not one that everybody can carry out all the time. You don't like it, take it up with the AOL and Hotmail guys, not me, OK? :) --- Begin Message --- --- Begin Message ---This is an automatically generated Delivery Status Notification. Delivery to the following recipients failed. [email protected]Reporting-MTA: dns;mc2-f24.hotmail.com Received-From-MTA: dns;listserv.vt.edu Arrival-Date: Sun, 11 Apr 2004 22:07:13 -0700 Original-Recipient: Final-Recipient: rfc822;[email protected] Action: failed Status: 5.0.0 Diagnostic-Code: smtp;550 Requested action not taken: mailbox unavailable--- Begin Message ------ End Message ---Your message dated Sun, 11 Apr 04 23:05:06 GMT with subject "�����η� ��û�ϼ��� 6�����̻�ٹ��� clrqy lhu iotgnuhca" has been submitted to the moderator of the TURBVIS list: [email protected]--- End Message --- Attachment:
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