On Thu, 10 Aug 2006, Ken Simpson wrote:
I've had a a situation in the past that required this same application.
I ended up using amavisd-new with custom views for incoming and outgoing
mail. For spam originating from inside, it was dropped completely, for
spam originating from the outside, subject was rewritten.
Can you elaborate on the situation off-list? It seems to me that
stopping outbound webmail spam is something that would not be
profitable for an ISP. I am wondering what the ISP's motivation is to
solve this problem.
I'll answer on-list since this answer can benefit others. The primary
reason that the ISP wants to block outbound webmail spam is because the
100s of BLs on the Internet end up blocking large segments of the IP space
due to spam reporting by end users. The spammer can end up "burning"
quite a few IPs before the feedback loop of user->spam
report->BL->ISP->block is completed. Therefore the ISP wants to be
proactive and shut off the spam before it even starts. Even if it means
losing revenue.
Hank Nussbacher
http://www.interall.co.il
Regards,
Ken
Hope this helps.
-Michael
--
Michael Nicks
Network Engineer
KanREN
e: [EMAIL PROTECTED]
o: +1-785-856-9800 x221
m: +1-913-378-6516
Hank Nussbacher wrote:
Back in 2002 I asked if anyone had a solution to block or rate limit
outgoing web based spam. Nothing came about from that thread. I have an
ISP that *wants* to stop the outgoing spam on an automatic basis and be
a good netizen. I would have hoped that 4 years later there would be
some technical solution from some hungry startup. Perhaps I have missed
it. What I have found so far is:
Detecting Outgoing Spam and Mail Bombing
http://www.brettglass.com/spam/paper.html
SMTP based mitigation - thing on HTTP/HTTPS
Stopping Outgoing Spam
http://research.microsoft.com/~joshuago/outgoingspam-final-submit.pdf
Research paper - nothing practical
Throttling Outgoing SPAM for Webmail Services
http://www.ceas.cc/papers-2005/164.pdf
Research paper - nothing practical
ISPs look inward to stop spam - Network World
http://www.networkworld.com/news/2004/071204carrispspam.html
Bottom line - no solution
So I am trying once again. Hopefully someone has some magic dust
this time around.
Thanks,
Hank Nussbacher
http://www.interall.co.il
--
MailChannels: Reliable Email Delivery (TM) | http://mailchannels.com
--
Suite 203, 910 Richards St.
Vancouver, BC, V6B 3C1, Canada
Direct: +1-604-729-1741
+++++++++++++++++++++++++++++++++++++++++++
This Mail Was Scanned By Mail-seCure System
at the Tel-Aviv University CC.