Re: Large Mail Provider Throttling

[Suresh Ramasubramanian <suresh () outblaze com>]

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