North American Network Operators Group

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Re: Misguided SPAM Filtering techniques

  • From: William Herrin
  • Date: Tue Oct 23 21:12:41 2007
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On 10/23/07, Owen DeLong <[email protected]> wrote:
> I want to make it clear... I don't mind people filtering either 25 or
> 587,
> but, blocking both is highly unacceptable.  Even more unacceptable
> in my opinion is hijacking connections to either off to your own
> man-in-the-middle attack server.


You must have been irked by the airport wireless in ABQ then. I
couldn't figure out why my ssh connection was failing until I checked
the DNS and relized that even after clicking "free access" button in a
web browser they returned for almost every name requested.

I can understand blocking outbound tcp 25. I wish more folks did it.
Blocking 587 makes no sense. The whole point of 587 is that its the
authenticated mail submission port. Its of very limited use to
spammers. Guess we'll have to move it to 443 too. ;)


William D. Herrin                  [email protected]  [email protected]
3005 Crane Dr.                        Web: <>
Falls Church, VA 22042-3004