munity, about whether you’re trying to solve a problem or define a new research area,” admits Brunskill. Many successful projects are trying to solve immediate societal problems, but researchers in the community are nonetheless convinced there are possibilities for serious long-term science.

“For example, I believe computer
scientists can lead the way in combin-
ing data- and model-centric methods to
design proactive plans that can mitigate
the spread of diseases or the shortages
of food and water following a disaster,”
Horvitz explains. “The idea is to use
computational models and data from
similar situations to make inferences
about actions that promise to have a
high expected value. Partial plans might
be generated proactively with the goals
of maximizing the survival of people
who have been injured or are trapped.
The details of such ‘contingency plans’
for transporting medications, food, and
water could be instantiated in real time
based on sensor data.”
In the meantime, the field’s lack of
definition suits many scientists just
fine. “Fundamental research in this
domain is about understanding the
ground realities,” says Subramanian,
who points out that in “the 1970s, you

“In computer science,
you don’t often have
the sense that
you’re in a noble
profession,”
says eric horvitz.
“this is an
interesting outlet for
passionate people.”

didn’t have specialties like architec-
ture or networking. You were trying to
get things done.”
“In computer science, you don’t
often have the sense that you’re in a
noble profession,” says Horvitz. “This
is an interesting outlet for passionate
people.”

Further Reading
Beshah, T. and Hill, S.
Mining road traffic accident data to
improve safety: role of road-related
factors on accident severity in Ethiopia,
Proceedings of AAAI Artificial Intelligence
for Development (AI-D’ 10), Stanford, CA,
March 22–24, 2010.
Brunskill, E. and Lesh, N.
Routing for rural health: optimizing
community health worker visit schedules,
Proceedings of AAAI Artificial Intelligence
for Development (AI-D’ 10), Stanford, CA,
March 22–24, 2010.

Leah hoffmann is a technology writer based in Brooklyn, ny.

© 2011 aCM 0001-0782/11/05 $10.00

Cybersecurity

Microsoft Dismantles Rustock Botnet

Microsoft has shut down what a spokesperson for the company’s Digital Crimes Unit described as a notorious botnet that was sending some 30 billion junk email messages each day. Botnets typically consist of thousands of compromised computers remotely controlled for the purpose of executing denial-of-service attacks, spreading malware, or participating in other nefarious activities. In the case of rustock, which reportedly consisted of hundreds of thousands of infected computers controlled by several command servers, the main activity was to send junk email.

rustock’s anonymous operators used the botnet to hawk low-cost pharmaceuticals, urge recipients to participate in fake lotteries, and otherwise clutter inboxes with unsolicited missives. following the

shutdown of the botnet in March, email-monitoring agencies reported a significant downturn in junk email. as one example of the message volume rustock was capable of achieving, a single rustock computer that Microsoft researchers monitored leading up to the botnet shutdown was reportedly sending email at the rate of 10,000 pieces per hour.

the shutdown strategy involved a two-pronged approach: a legal initiative to seize the botnet’s control servers and a technical initiative to block the infected client computers from establishing connections to new command servers. after an investigation by Microsoft’s Digital Crimes Unit and successful legal pleadings, Microsoft’s operation b107 resulted in the simultaneous seizure by the U.s. Marshals service of servers at five hosting

providers in the U.s.

Microsoft worked on the rustock initiative with several organizations, including the Dutch high tech Crime Unit, to dismantle command servers outside the U.s. and China’s Computer emergency response team to block the registration of domains that rustock-infected computers could have contacted for future directives. Microsoft’s Digital Crimes Unit is now working with Internet service providers to identify and cleanse the computers infected with the rustock malware.

“It is impressive that
Microsoft managed to get this
operation working so smoothly,”
says Johannes Ullrich, chief
research officer at the sans
Institute. according to Ullrich,
the initiative’s legal aspect shows
maturity about the process of
shutting down a botnet. “It’s no
longer a bunch of guys deciding
they don’t like a botnet and
taking technical measures to
shut it down,” Ullrich says.