Re: educating rDNS violators

From: Bryan S. Sampsel (bsampsel_at_libertyactivist.org)
Date: 08/29/04

  • Next message: Gideon T. Rasmussen, CISSP, CISM, CFSO, SCSA: "U.S. National Security Awareness Day (NSAD)" 
    Date: Sun, 29 Aug 2004 07:58:37 -0600 (MDT)
To: security-basics@securityfocus.com

    Authenticated SMTP. Sendmail has it. I've even seen it on some Windows
    based email servers. Can't remember if Qmail has it or not though...

    And there's some method of kludging the client to use the POP or IMAP
    client to send instead of receive.

    You might also have the client VPN in and their VPN IP is placed into the
    trusted range for relay...and rDNS wouldn't break anything then. Just a
    thought.

    Sincerely,

    Bryan S. Sampsel
    LibertyActivist.org

    Mark Reis said:
    > A question for those who have implemented rDNS restrictions.
    >
    > In the case of a mail server with roaming users, how do you deal with
    > roaming users? A majority of our users travel to conferences and use
    > secure IMAP and SMTP to send their mail. Perhaps this is a
    > misconception, but I thought that some mail clients attempt to portray
    > themselves as a SMTP server relaying through the main mail server. If
    > we have users off traveling and having their email is blocked while they
    > were connected at a hotel with bad rDNS entries, I'd be getting ticked
    > off calls.
    >
    > Any suggestions?
    >
    > Thanks,
    > Mark
    >
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