Re: Re: SRS: is there a stable implementation for postfix yet?

On Mon, 27 Mar 2006, Tom Lahti wrote:

> SRS does not prevent bounce-spam "in a tiny minority of cases", it 
> completely eliminates it.  I am eliminating 80,000+ per day using SRS 
> signing and have not had a single spam report from a user since 
> implementation that involved a fake DSN.
> 
> SRS signing COMPLETELY eliminates fake-DSN spam, and without the 
> possibility of rejecting a real one.  I am not saying "probably", I 
> am saying it DOES.  I've been doing it for quite some time now.

Same here, with one caveat.  Some braindead MTAs have a policy of
rejecting localparts from any domain containing '+' (same idea as rejecting
localparts beginning with SRS).  Of course, this breaks many things
apart from SRS.  For these domains, I have to turn off SRS signing.
As a consequence, I cannot accept DSNs from such braindead domains
(since they also relay bounce spam).   Something for Johann to keep
in mind - and a caution against apply a "no SRS" policy to any
except a few braindead domains acting as an open relay.

-- 
	      Stuart D. Gathman <[email protected]>
    Business Management Systems Inc.  Phone: 703 591-0911 Fax: 703 591-6154
"Confutatis maledictis, flammis acribus addictis" - background song for
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