On Friday 13 May 2005 23:51, Ryan L. Sun wrote: > If an incomming email is from a IP listed in IP whitelist, we don't > need to check it at all. > The whitelist I mentioned here is a large-scale one. Say Microsoft and > Yahoo's IPs should be added to IP whitelist since we suppose they > won't send spams.
Uhh.. no. Yahoo IPs do send spam, when a lovely 419 scammer actually uses a real Yahoo account to send the scam. It does get shut down fairly fast though.. sometimes. The only way you'll get an accurate whitelist is to determine with sending servers you trust. A greylisting engine -might- help you with this if you bent it enough. Once you know you trust a sending server, somehow you need to tell your MTA to not feed that message to SA. Alternately, feed it to SA anyway, but make an RBL out of the whitelist and do an rbl check that scores -ve points. Then wait for that IP you trust to be misconfigured and turned into an open relay.... :> Hopefully, even though you trust an IP to not send you spam, you don't trust it to not send you viruses.
