Internet users can be spared up to 95 percent of the spam sent their way if their ISPs use anti-spam filters, according to a report released today by the Federal Trade Commission.
In a five-week study, the FTC created 150 covert e-mail addresses and assigned 100 of them to two ISPs that use spam filters and 50 to an ISP that does not use filters.
The agency then posted the covert addresses on 50 Internet sites such as blogs, chat rooms, message boards and USENET groups.
After five weeks, the addresses at the unfiltered ISP got hit with 8,885 spam e-mails, while one of the filtered ISP addresses received 1,208 spam e-mails and the other received 422.
Addresses listed on Web sites were much more likely to be harvested by spammers than those listed on blogs, message boards or chat rooms, according to the FTC.
Unfiltered addresses that were listed on Web sites received 99.6 percent of the total 8,885 spam e-mails received in the unfiltered category.
In contrast, unfiltered addresses that were listed on blogs received .38 percent, and those listed on USENET groups received .02 percent of the total.
"The fact that the vast majority of spam sent to harvested addresses in this study was never delivered to consumers inboxes demonstrates the relative effectiveness of the two ISPs spam filters," the FTC concluded.
"This encouraging result suggests that anti-spam technologies may be dramatically reducing the burden of spam on consumers."
The FTC advised that users can prevent their e-mail addresses from being harvested by masking addresses to confuse harvesting software, such as spelling out the symbols for "at" and "dot".
In the five-week test period, unmasked e-mail addresses received more than 6,400 spam e-mails, while masked addresses received just one.
However, in an end note, the commission pointed out that masking is not foolproof and that at least one harvesting program appeared to capture the masked address by converting the spelling of "at" and "dot" into the symbols.
The regulators accolade for anti-spam technologies comes in the face of an ever-expanding problem with unsolicited commercial e-mail, which seemingly has not been mitigated by the CAN-SPAM Act of 2003, a law that the FTC was charged with enforcing.