On 10 Aug 2006, at 22:07, Barry Shein wrote: [...]
The vector for these has been almost purely Microsoft Windows.
I wonder. From the point of view of a MX host (as opposed to a customer-facing smarthost), would TCP fingerprinting to identify the OS and apply a weighting to the spam score be a viable technique?
We have been doing that in our traffic shaping SMTP transport for a while now. We have found a 95% correlation between spam sources and Windows hosts. If you drill down to specific versions of Windows, the correlation is even higher. For _blocking_ connections (as opposed to, say, just slowing them down), you must combine host type with reputation information. Regards, Ken -- MailChannels: Reliable Email Delivery (TM) | http://mailchannels.com -- Suite 203, 910 Richards St. Vancouver, BC, V6B 3C1, Canada Direct: +1-604-729-1741