> [...ao.com...] > At the point where we finally sold the domain to be rid of this issue > (and make a few $) we were processing in excess of *300000* messages > a day. This is for a 7 person company. It was more than 50% of the > email processed by our ISP. Our DSL router throttled the SMTP > requests so we could SOME work done during the day.
Hm? You're implying your ISP was handling your mail, but then you imply you were handling your own mail. I'm a little confused. The main reason I'm writing, though, is a bit different. That there's a company I know that was in a somewhat similar position - they were getting so much spam bounce blowback that they were shutting off all incoming SMTP during the day to keep the machine up. I wrote a very lightweight SMTP server for them; it accepts connections and talks SMTP until it gets a valid recipient, and then - and only then - connects through to the real SMTP server and passes protocol both ways. It was very good at turning away mail to unknown addresses. There was one time when some host in south-east Asia opened about 100 parallel connections and started a dumb-as-rocks dictionary attack. It turned away many tens of thousands of unknown recipients in something like thirty seconds, and, even knowing exactly when it happened, I couldn't find the blip on our load graphs - it was drowned out by the noise. If I hadn't been reading the logs for other reasons and stumbled across it I never would have known it happened at all. Obviously, it's of no direct use to you now that you don't hold ao.com any longer. But in case you - or anyone else - is interested, I got their approval to open the code up; it's available to anyone who cares to fetch a copy. ftp.rodents-montreal.org:/pub/mouse/misc/mail/shim/ is the place to look for those interested. /~\ The ASCII Mouse \ / Ribbon Campaign X Against HTML mo...@rodents-montreal.org / \ Email! 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B
