• by Shankar Gupta , June 23, 2005

In a move to cut down on spam and phishing schemes, MSN's Hotmail service Wednesday began moving e-mails that do not have sender identification authentication data into people's junk mailboxes. "Sender ID is aiding MSN Hotmail in its efforts to help protect customers from phishing, and this week MSN also made Sender ID "warning alert" notifications visible via a new safety bar in the MSN Hotmail user interface," an MSN spokesperson said.

Sender ID, which was developed by Microsoft, is designed to verify whether an e-mail message was sent from the domain listed in its header information. The program compares the IP address of the server against a registered list of IP addresses submitted by domain owners. If the two do not match, then the authentication fails.

In addition to moving messages that aren't authenticated into the junk mail box, MSN now marks them with a disclaimer stating that the message's sender could not be authenticated.

Matt Blumberg, CEO of Return Path, an e-mail marketing firm, said MSN's move could be seen as aggressive toward marketers. "They're taking a pretty hard-line approach to it," he said. "In the world of carrot and stick, they're taking a real stick approach to it. They're saying 'If you don't authenticate, we're going to put it in the junk mailbox, and we're going to put a big disclaimer on your e-mail.'"

But, Blumberg said, MSN's move will be positive for marketers, because Sender ID authentication is easy to set up, and in the long run, the service could be used to combat spam, while leaving legitimate direct marketers' mails alone.

"We think of it as the first step in a multistep process to start rooting out spam," Blumberg said. "What's really going to have to come into play now is a reputation and accreditation system. Authentication and reputation are two pretty different things, and you need both to solve spam."

Blumberg added that once the mail's sender can be authenticated, systems to track the reputations of commercial mail senders can be used to separate the spammers from other direct marketers. Blumberg's firm, Return Path, is expected Monday to announce the beta release of a reputation tracking system for e-mail senders, dubbed Sender Score.