Geolocation to strengthen quantum security

Deliver to one address only.

A telecommunications researcher is proposing to heighten the security of quantum communications with geographic information.

Using a process called 'unconditional location verification', sensitive communications only take place if the receiver is at a predetermined location.

The technique builds on existing quantum communications technology, where a message is encrypted and sent via quantum particles - qubits - along optical fibre.

Normally, a key to decrypt the message is then delivered via conventional channels like wireless Internet.

University of NSW researcher Robert Malaney proposes to deliver the key along at least three paths, such as to three wireless towers near the receiver.

Upon receipt of the three keys, the receiver is required to instantaneously send a return message using information from decoded qubits.

Using knowledge of transmission speeds, the sender is able to determine if the receiver is at the designated location.

"Incorporating geography opens up a whole new range of security paradigms not previously available," Malaney told iTnews.

"Now you can authenticate for the first time that the receiver you are communicating with is truly at the location it is supposed to be."

While it is still possible to disrupt communications, Malaney said unconditional location verification would be impossible to spoof.

Even if the encrpytion password had fallen into the wrong hands, it could not be used unless at the predetermined geographic location.

Communications - such as a bank transaction - would not take place if unauthorised, and the worst that could happen is no transaction, Malaney said.

Malaney expects the technology to appeal particularly to banks, and is currently seeking collaborators with pre-existing quantum communication technology to build a prototype.