spf-discuss
[Top] [All Lists]

Re: Attacking the throwaway-domain problem

2003-10-14 20:45:18
In <20031014224831(_dot_)GA15773(_at_)thyrsus(_dot_)com> "Eric S. Raymond" 
<esr(_at_)thyrsus(_dot_)com> writes:

[...] The bind we can set up, given widely
deployed SPF, is that

(a) If a spammer spews with an IP/domain combination that doesn't match,
    he loses -- the BL's spam traps ignore him, but all SPF-aware MTAs send 
    the mail to /dev/null.

(b) If a spammer spews with an IP/domain combination that *does* match,
    SPF-aware mailers won't bin his stuff, but spam traps catch it and
    the BL eats his his domain.

So a two-layer check should work pretty well.


Exactly.

The SpamCop DNSBL is able to catch new spammer activity from an IP
address very quickly, often in a matter of only a few hours.  While
domain names may not be that expensive (and their price will continue
to fall), that still is going to be a chunk of change that a spammer
will have to spend.  More over, this knocks out the casual spammer, or
the spammer who thinks they are legitimate.  


-wayne

-------
Sender Permitted From: http://spf.pobox.com/
Archives at http://archives.listbox.com/spf-discuss/current/
To unsubscribe, change your address, or temporarily deactivate your 
subscription, 
please go to 
http://v2.listbox.com/member/?listname(_at_)©#«Mo\¯HÝÜîU;±¤Ö¤Íµø?¡