Microsoft will filter outgoing messages on its consumer
mail services and is busy developing "proofing" technologies, in
its continuing fight against unsolicited commercial
e-mail.
More than 14.5 billion spam messages are sent each day, said
Ryan Hamlin, general manager of Microsoft's Security Technology
& Strategy group, citing figures from antispam supplier
Brightmail.
Microsoft's Hotmail web-based e-mail service receives 2.7
billion spam messages a day.
In the coming months Microsoft will apply spam filters not only
to incoming mail on its Hotmail and MSN services, but also to
outbound mail. The filtering will kick in when users send a large
number of messages and is intended to help stop abuse of
Microsoft's services by senders of spam, Hamlin said.
He called out to internet service providers (ISPs) and other
e-mail service providers to do the same.
"All of the ISPs and large senders of mail need to be filtering
on the outbound side," he said. "There is a lot of abuse happening.
We need to have better outbound filtering to look for people that
are abusing our systems."
Comcast, a large US cable internet access provider, last month
said it was cutting off internet service for some customers whose
computers had been hijacked to relay spam messages.
Filtering, however, is only part of Microsoft's technology attack
on spam. The company is also investing heavily in proof and
prevention utilities. Filters will really only work well after
proper spam-proofing and prevention technologies have been
applied, Hamlin said.
"Protection today has been very reactive. We want to make it
very proactive, and we think the way to do that is by having great
proof and prevention technologies," he said.
One proofing technology that Microsoft is working on sends a
challenge in the form of a computational puzzle to the sender of a
message if the filtering system suspects a message may be spam. The
sender, or the sender's computer, would have to solve the puzzle to
validate the legitimacy of an e-mail message.
Solving a challenge would take little time for a regular e-mail
sender's computer but would overwhelm the computing cycles of
someone sending large amounts e-mail. The technology is now being
developed and should be ready within a year, Hamlin said.
The challenge system would work in concert with other
technologies Microsoft is developing as part of its co-ordinated
spam reduction initiative announced in February. The plan also
includes Microsoft's SmartScreen filtering technology, a sender
authentication technology called Caller ID for E-mail and "white
lists" that contain certified e-mail senders.
Microsoft uses many of its antispam technologies in Hotmail and
MSN, and last week delivered the Intelligent Message Filter for
Exchange, a spam filter based on SmartScreen, for the Exchange
e-mail server product.
Microsoft is battling spam on several fronts and has repeatedly
said there is no silver bullet to solve the onslaught of spam. The
software maker advocates stronger legislation and enforcement to
attack spam and those who send it and has called for industry
collaboration and consumer education on the topic.
Joris Evers writes for IDG News Service