A team of researchers at MIT have figured out how to partially compromise quantum cryptography systems through a creative interpretation of the entanglement principle. In a system protected with quantum cryptographic principles, bits of information are encoded by assigning meaning to the polarisation of individual photons of light (up-down could mean a one, left-right could mean a zero) and thus exchange keying material. The very act of observing quantum particles changes their properties and thus destroys the data encoded in the particles, so in theory an eavesdropper Somewhere Out There listening in would corrupt the stream of data by damaging …

In slightly less technical terms, researchers at the Toshiba Research Europe facility in Cambridge, England have figured out how to make it harder for eavesdroppers to steal keying information from a quantum cryptosystem (registration required, Bugmenot has login credentials for this site). For an attacker to have a chance at breaking a quantum cryptosystem, he or she would have to splice a tap into the optical fibre which connects the two crypto units and record the pulses of light that encode the key used to encrypt the data. There are ways to use the principles of quantum mechanics to detect …