Microsoft's Hotmail will offer people the option to automatically redirect suspected junk mail into a special folder using a filter that captures all messages addressed to the recipient on an email's "bcc" line. Recipients can then check the folder to determine whether the message was unsolicited.
The issue of unsolicited bulk email, or spam, is one of the most controversial by-products of the Net. Internet service providers say spam overburdens their servers, while privacy advocates say spam marketers trample privacy rights. Net users, meanwhile, hate having their email in-boxes filled with unwanted messages pitching products and services.
Internet companies that offer email, such as Web portals and ISPs, have spent considerable resources to fight the problem. Giants such as America Online have taken suspected spammers to court, and many states have enacted legislation to fight the proliferation of spam.
Community-driven efforts to choke spam also have been attempted. Internet hosts, which collectively share the burden of passing email and other packets of data to one another, can theoretically police their own systems by refusing to let spam through.
Hotmail's addition of the filter follows the service's high-profile decision late last year to join a controversial anti-spam program known as the Mail Abuse Prevention System (MAPS)--and it could be an indication that the large-scale policing program has not been effective.
MAPS identifies and blacklists Internet servers that act as conduits for large volumes of junk email. The filter, known as the Realtime Blackhole List (RBL), received a big boost from Microsoft's endorsement.
Despite today's addition of the new filter, Microsoft denied that its participation in the RBL has been a failure.
The in-box filter is not a replacement, but an add-on to the RBL filter, according to Deanna Sanford, a Microsoft spokeswoman. Sanford also said the move was not in response to criticism over use of the MAPS blacklist.
"This is the next step to give even more individual control for users than before," Sanford said.
But many people say they believe the list does little to stop spam while potentially blocking legitimate messages. In addition, some businesses have said they were blocked without warning or justification.
"Based on the (Internet Protocol) address source, you can sometimes very reliably say the email is likely to be spam, but unfortunately not every source of spam has that marking or indication," Catlett said. "Spam gets in some places without those obvious signs."
Still, some Hotmail users said they had seen a difference in the amount of spam they received since Microsoft instituted the RBL, which uses various techniques to block junk mail.
Joshua Slive, a part-time computer consultant who says he closely follows spam-blocking techniques, said he saw junk mail to his Hotmail account drop by more than 75 percent after Microsoft installed the RBL. "The advantage of these techniques in comparison to the 'in-box protector' is that they are not nearly as easy to get around," he said.
Hotmail's in-box filter method is not new. Yahoo's free email service, Yahoo Mail, implemented an in-box filter last December. Although the company has not disclosed how the filter works, fearing that such a move would tip off spammers, many people have applauded the feature.
Hotmail's new filter also has received praise from some members.
"I usually get a dozen or so spams every couple of days in my Hotmail in-box, and that's using a number of subject-based filters and (apparently) the RBL," Alan Krueger, a software engineer and member of an anti-spam newsgroup, wrote in an email. "By turning on Hotmail's new filter, I've gotten *NO* spam in my Hotmail in-box since Tuesday afternoon, which to me is quite impressive."
Another newsgroup participant agreed: "I turned the filters on the other day. No spam. Not one. Period. For the first time in months, my Hotmail mailbox is quiet."