Yes, but in the dial world you know who is sending mail through your server, so leave port 25 open for dial users only, and have your non-dial users to send to port 587 via SMTP AUTH.
You should be able to trace dial offenders easily through your logs and freeze their accounts if there's a problem. Since you control the network they're using to access the internet, you can enforce security at the dial-up access level rather than at the SMTP level, which is just as good if not better. For those using other ISPs to connect to your mail servers, that's when you could enforce SMTP AUTH. For monitoring customers, a simple report showing incoming and outgoing totals, ordered by volume, should show you quickly who potential offenders might be. There's no excuse for us to say we're fighting spam and not police our own networks. A simple report delivered nightly via email could show incoming and outgoing volume for each domain, ordered by decreasing volume. It takes less than a minute to scan the top and make sure there are no potential problems. That's a minute a day we can afford to ensure there are no violations we need to investigate, as well as protecting our mail servers from abuse that could affect all customers. So I guess that, instead of not being able to afford to do it, I would argue that you can't afford _not_ to do it. Darin. ----- Original Message ----- From: "Charles Frolick" <[EMAIL PROTECTED]> To: "Ted Galerneau" <[EMAIL PROTECTED]> Sent: Wednesday, December 08, 2004 10:34 AM Subject: Re[2]: [IMail Forum] Lycos goes limp One thing that seems to be getting ignored is the fact that there are thousands of small ISP's that rely on wholesale dial to provide nationwide access, I certainly do. The problem is that we have zero control over where they are coming from and what type of filtering is done. The only time they touch my network is when they pull up our site, send/recieve mail, or use the news server. The dial providers do not restrict port 25, because it would force the settings change for millions of subscribers (default for all clients is 25, not 587, and many mail servers don't support 587). We are also a hosting provider, and our customers an send mail through their hosted server, we respond to complaints quickly, but we are not set up to, nor do we have the manpower to police all outgoing mail from these servers. The added expense to do such would put us out of business. We do what we can, but with so many cut rate hosting providers out there, margins are very thin, the ISP has to pay the bulk of our bandwidth cost. -- Best regards, Charles mailto:[EMAIL PROTECTED] To Unsubscribe: http://www.ipswitch.com/support/mailing-lists.html List Archive: http://www.mail-archive.com/imail_forum%40list.ipswitch.com/ Knowledge Base/FAQ: http://www.ipswitch.com/support/IMail/ To Unsubscribe: http://www.ipswitch.com/support/mailing-lists.html List Archive: http://www.mail-archive.com/imail_forum%40list.ipswitch.com/ Knowledge Base/FAQ: http://www.ipswitch.com/support/IMail/
