The global volume of junk mail plummeted Tuesday after network providers disconnected a California web hosting firm cited by the Washington Post and others for hosting spammers. Global Crossing and Hurricane Electric disconnected McColo Corp. after receiving inquiries about the firm's activity from Post security blogger Brian Krebs. SpamCop and other organizations that monitor junk mail reported an almost immediate drop in spam levels in the wake of the disconnects.
In September a similar fate befell another web host, Atrivo/Intercage, which for several days had its traffic refused by all its connectivity providers (as documented by Renesys). But as often happens, Atrivo soon found a new provider who would accept its traffic.