One single web host was behind 75% of all email spam

Following an investigation by Brian Kreb at Washington Post that exposed the web hosting firm McColo as one of the main originator of spam on the Internet, the ISPs providing Internet access to the firm pulled the plug on them (effectively shutting them down).
The effect this had on the world’s spam levels was amazing. The amount of spam immediately dropped by between 66-75%, depending if you look at numbers from spam trackers IronPort (66%) or Spamcop (75%). A pretty amazing number no matter which one you pick.



