U.S. Named Top Spam Exporter
Sophos said an analysis of the spam it filtered worldwide in a recent two-day period revealed that 56.7 percent came from the United States. Canada was a distant No. 2 on the "dirty dozen" list, responsible for 6.8 percent, followed by China (6.2 percent) and South Korea (5.8 percent).
The figures mesh with a United Nations report in November that found 58.4 percent of spam originated in the United States. The United Nations estimates spam has an annual global cost of $20.5 billion, covering IT costs, lost productivity and maintenance of help desks.
The U.S. production of spam has long been a sore point with the European Union, which instituted a stricter opt-in requirement for commercial e-mail. The U.S. CAN-SPAM Act requires commercial e-mailers to honor unsubscribe requests.
Sophos tracked a rise in spam from compromised computers, which spammers use to route spam by planting Trojan horses and worms on them. It found that 30 percent of spam messages were sent this way.