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Unsolicited bulk or "junk" e-mail, commonly called spam, now comprises at least 50 percent of all e-mail being sent through the Internet, according to figures compiled by Brightmail Inc., a San Francisco-based maker of anti-spam software.
"Earlier this year, Brightmail predicted that the volume of spam would reach 50 percent of Internet e-mail by the end of 2003, and it did this July," says Enrique Salem, president and CEO of Brightmail. "In less than two years, spam messages have increased from 8 percent of all e-mail traffic to more than half -- and we expect this trend to continue."
In July Brightmail identified more than half of the 61 billion e-mail messages it filtered as spam. Brightmail claims to filters nearly 10 percent of worldwide e-mail and says its estimates are the most statically relevant e-mail sample available.
Why so much e-mail? Brightmail says it's economics. Individual spammers are capable of sending hundreds of millions of e-mail messages each day -- at essentially the same cost as sending out a single message. Therefore, it takes very few recipients to respond to those messages to make a spammer profitable. And barriers to entry are extremely low with minimal hardware and experience needed.