[66758] in North American Network Operators' Group
Re: Large Mail Provider Throttling
daemon@ATHENA.MIT.EDU (Suresh Ramasubramanian)
Thu Jan 22 22:05:38 2004
Date: Fri, 23 Jan 2004 08:34:54 +0530
From: Suresh Ramasubramanian <suresh@outblaze.com>
To: Aaron Thomas <athomas@deltacable.com>
Cc: nanog@merit.edu
In-Reply-To: <B0394447344@yoda.dccnet.com>
Errors-To: owner-nanog-outgoing@merit.edu
Aaron Thomas [1/23/2004 8:28 AM] :
> Sender Permitted From (http://spf.pobox.com/) attempts to eliminate Joe
> Dropping from domain.com by doing a look up on a TXT record similar to
[...]
> As this project is fairly new, there aren't many large domains making use of
> it, and the tools available aren't mature enough for some email
What I described in my earlier email (helo filtering) is aimed at the
same result. Only, it has to be done on a case by case basis. And it
does allow road warriors.
The second way (slightly more radical, prone to a little more collateral
damage, but does stop a LOT of spam) - stop accepting mail from commonly
forged freemail domains if the mail originates from an IP with either
* no rDNS
* generic (dialup / cable / dsl) pattern rDNS
--
srs (postmaster|suresh)@outblaze.com // gpg : EDEDEFB9
manager, outblaze.com security and antispam operations
