News Quantum makes big leap for cryptography

From the Inq, via NewScientist:

THE FIRST QUANTUM cryptography network has been built by boffins in Cambridge, Massachusetts.

The Quantum Net (Qnet) was built by at BBN Technologies in Cambridge, as part of the Pentagon's Defence Advanced Research Projects Agency.

The data in the network is encrypted using keys determined by the exchange of a series of single, polarised photons.

According to the New Scientist, the network harnesses the quantum quirks of photons sent between users. Any attempt to intercept the photons will disturb their quantum state and raise the alarm.

More here, and the original NS article can be found here

 

It was only abount a month ago that they first transmitted a quantum encoded peice of data. I believe it was transmitted between two banks just a few miles apart. The problem with this technology is that you can't have any interceptions whatsoever which means you can only transmit as far as your optical cable can reach.