AN OFFICE EXECUTIVE SPENDS MORE THAN 4 hours checking, reading, and replying to emails. Out of the 4 hours, he or she spends close to an hour deleting junk mail. Spamming has grown to be a threat not just for the desktop, IT managers are attempting desperate measures to block spam at the mail gateway itself.

Pavni Diwanji was one of the first adopters of email identity at Yahoo, and has experienced spam-connected hurt first hand. After a successful sell-out of her previous startup, Kendara, to Excite@Home, she led the client software division, including email, instant messaging and security products at Excite@Home until September 2001. Six months later, she was back into the startup fray, this time attacking the $10 billion anti-spam market. Mail Frontier, her second startup, began in 2002 when “it was not the best of times to explore.”

Today Diwanji has got some excellent traction with her anti-spam gateway products. “On average, a spammer needs response rates of only 0.1% to make sending worthwhile. Now programmers are beginning to figure out how to identify spam pretty accurately and remove it automatically from your in-box. We have gone further and have built in some smart tools to kill the spam at the gateway itself,” says Diwanji.

The MailFrontier system includes a “white list,” the opposite of a blacklist. This is a dynamic list designed to admit all mail from specified senders: That’s anybody in your electronic list of contacts, plus anyone you write to. Their mail will not be blocked.

Then come the blacklists of known spammers, as well as the content filters to stop all mail containing red-flag content. In addition, a challenge component will be used in ambiguous cases to ask the sender of suspicious mail to send a quick reply in order to validate their status as a legitimate sender. That may sound like a lot of layers of defense, but such aggressive tactics are becoming increasingly necessary. “We have also created a dynamic eProfile - a distinct blocking profile based on the nature of a corporation’s communication. The eProfile is constantly updated, automatically tuning its spam blocking capabilities in order to optimize effectiveness specifically based on the mail characteristics of the corporation,” says Diwanji. Sold on per-user (retail) or per-seat (enterprise) basis, Mail Frontier has attacked the spam world with many strategies.

At the recent DEMO 2003, the products won some good reviews, though the dependence on Outlook could be a possible deterrent in adoption. Mail Frontier has been funded by NEA and Draper Fisher investing over $5 million recently. Diwanji says the fight has just begun.