Re: spam blocking experiences with MXs

[Robert Waldner <waldner_(_at_)_waldner_(_dot_)_priv_(_dot_)_at>]

On Sat, 21 Dec 2002 09:13:58 EST, "Joseph C. Bender" writes:
>>So, delivering the spam instantly would cost you about 7.300 bytes, 
>> retries every 30 minutes for 5 days amounts to 45 kB or roughly 6 
>> times as many bytes.

>	Your math is slightly off.
>
>The MX-bouncer daemon doesn't even get that far.  It does a 450 after the
>redirect happens in pf.  So you'd just be doing the smtp protocol overhead
>up to that point.

Not right away, it first acknowledges "helo", "mail from", and "rcpt to".
 The 450 is sent after receiving "data".

If I talk to the bouncer on localhost like:

waldner_(_at_)_fsck->~ $ telnet localhost 8025
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
220 fsck ESMTP spamd IP-based SPAM blocker; Sat Dec 21 18:52:57 2002
helo fsck.intern.waldner.priv.at
250 Hello, please to meet you
mail from:<waldner_(_at_)_fsck_(_dot_)_intern_(_dot_)_waldner_(_dot_)_priv_(_dot_)_at>
250 You are about to try to deliver spam.
rcpt to:<waldner_(_at_)_fsck_(_dot_)_intern_(_dot_)_waldner_(_dot_)_priv_(_dot_)_at>
250 And we will try to punish you for it.
data
450 SPAM. http://www.spews.org?x=127.0.0.1
Connection closed by foreign host.

and count the bytes with tcpdump, 1470 comes out.

cheers,
&rw
-- 
-- Q: How many marketing people does it take to change a lightbulb?
-- A: I'll have to get back to you on that.