New Quantum Cryptography System for Securely Sharing Information
Information is an ever growing asset with ever growing value, but just as it becomes more powerful our means of securing information must also grow stronger. Security systems that take advantage of quantum mechanics could be the technologies of choice in the future. Now researchers at the Center for Quantum Technology at the National University of Singapore have devised a new way to secure information that could one day be deployed in our devices.
It is not uncommon for someone to provide information, such as a pin number to a system for verification. Ideally you can trust the system, but sometimes you cannot and this is where the new system can help. It works by creating pairs of photons at one point, called Alice, and having Alice measure half of each pair. Alice then sends the other photons to the other point, called Bob, which then measures the photons. Bob then chooses which photons he wants more information about without revealing his picks to Alice. At this point both Alice and Bob wait a sufficient period of time that any quantum information they may have stored will have decayed. Now Alice can send Bob the information he wants and they can both process the data they have to arrive at information they want. This protocol is known as a 1-2 Random Oblivious Transfer (ROT) as neither party knows about the data the other has.
For their experiments, the researchers performed a random oblivious transfer of 1366 bits and it all finished in about three minutes. While that was done with optics covering a large area, it could potentially be integrated into microchips and allow us to walk around with quantum security devices in our pockets.