Certifiably Random, A New Quantum Road To Cheap Encryption

Introducing A Quantum Certification Process For RNG

It is very hard to create truly random numbers to ensure a secure encryption key, with nothing predictable about the algorithm generating them.  In order to try to deal with this complexity we have developed a number of workarounds, involving mouse movements or atomic clock digits among other other things.  Quantum encryption has the ability to create non-deterministic strings of characters which are random, and can also detect interceptions en route, but the hardware required is not cheap.

A new study, headed by David Drahi, out of the University of Oxford, UK, has demonstrated a way of generating random keys via quantum effects with relatively inexpensive and off the shelf parts.  The process involves shooting a laser light at a beam splitter, which is connected to a pair of detectors.  One detector is set to produce a zero result, while the other detects if the photon was reflected or transmitted by the beam splitter, to generate a single result.  The process is capable of producing 8.05 gigabits per second and is also capable of monitoring the process in real time to ensure the proper amount of photons are being produced to ensure randomness. 

There is no way to predict if a photon will pass through a detector or not, and the previous measurement has no impact on what the next photon will do, which is how this process does produce random results.  It does have to be monitored, if too few photons are sent then the number of measured events is too low to be random, too many and the number of positives will also become too predictable.  This process ensures only events which fall within a certain range are ever accepted, this vaildating the process was random, and therefor the results will be too.

Drop by Physicsworld for more details as well as links to the papers.