Spam increased 35% in November

"There's been a huge increase in spam volume," says David Mayer, a product manager at IronPort Systems, "from 31 billion spams a day on average in October 2005 to 63 billion in October 2006. But in November, we saw two surges that averaged 85 billion messages a day, one from Nov. 13 to 22, the other from Nov. 26 to 28.

"The October-to-November increase is higher than any other month we've measured," Mayer says.

Like other anti-spam vendors, IronPort puts the blame on a surge in botnet use, the increased use of image-based spam, and a rapid rise in the number of URLs registered by spammers. That combination, along with profit-driven innovation, has dramatically changed the spam landscape in 2006, said IronPort, which released its annual trend report earlier this week.