Skip Links

Hooked on photonics

BBN researcher builds hack-proof quantum cryptography network that uses photons to generate secure keys.

By , Network World
May 02, 2005 12:07 AM ET

Network World - CAMBRIDGE, MASS. - Chip Elliott is every hacker's worst nightmare.

Elliott, principal scientist at BBN Technologies , leads a team building the world's first continuously operating quantum cryptography network, a 12-mile snoop-proof glass loop under the streets of Boston and Cambridge.


Wider Net archive
Our collection of stories that go beyond the speeds and feeds of the network and IT industries.


Quantum cryptography uses single photons of light to distribute keys to encrypt and decrypt messages. Because quantum particles are changed by any observation or measurement, even the simplest attempt at snooping on the network interrupts the flow of data and alerts administrators.

While the technology is still in the pilot stage, Elliott envisions a day when quantum cryptography will safeguard all types of sensitive traffic. "It's not going to overnight replace everything we have," he says. But it will be used to augment current technologies.

Defense funding

BBN's research is funded by the Pentagon's Defense Advanced Research Projects Agency , so it's likely the government would be first in line to roll out the super-secure technology. Elliott predicts financial firms will deploy quantum cryptography within a few years and estimates that businesses in general will deploy within five years. The technology also could move to the consumer market - for example, in a fiber-to-the-home scenario to protect the network between a home and service provider.

"People think of quantum cryptography as a distant possibility, but [the network] is up and running today underneath Cambridge," Elliott says. The team of nine researchers from BBN, four from Boston University and two from Harvard University, have put together "a set of high-speed, full-featured quantum cryptography systems and has woven them together into an extremely secure network," he says.

The system is essentially two networks - one for quantum key distribution and one that carries the encrypted traffic. And although it's probably the world's most secure network, it's not protecting any real secrets, at least not yet. For this pilot phase, BBN encrypts normal Internet traffic such as Web pages, Webcam feeds and e-mail.

The network has 10 nodes. Eight are at BBN's offices in Cambridge, one is at Harvard in Cambridge, and another is across the Charles River at BU's Photonics Center.

In keeping with the traditional naming convention that IT security professionals use (see story ), the nodes are named Alice, Bob, Ali, Baba, Amanda, Brian, Anna, Boris, Alex and Barb.

Inside the BBN labs

Elliott works out of an unassuming lab in a two-story brick building on BBN's campus. A labyrinth of blue corridors leads to the two-room lab tucked away in the basement.

A mass of cords and wires snake from all varieties of electronics on a table. BBN built much of the optics and electronics that are housed on server racks, and there are several Windows and Unix machines. Pink neon wire is strung high above, and a server rack is embellished with glowing blue plastic cylinders - all props obtained from a comic book.

Our Commenting Policies
Latest News
rssRss Feed
View more Latest News