NTT uses reflected lasers for encryption
Random number sequences used in cryptographic systems are usually generated from mathematical formulae but by understanding the algorithms behind the formulae hackers can crack the encryption.
Using irregular physical phenomena to generate random numbers can achieve a higher level of unpredictability.
NTT has developed a system that can generate random numbers at speeds up to 4Gbit/sec based on the irregular oscillation in the output light of a semiconductor laser whose output light is reflected by a mirror and injected back into the laser.
The technology is ‘a few years’ away from commercialisation.
Source | ElectronicsWeekly