Generation of information theoretic secure keys using a chaotic semiconductor laser

We demonstrate a method for information theoretic secure key generation based on practical physical limits of continuous data acquisition from a rapidly fluctuating random signal generated by a chaotic semiconductor laser and transmitted over an optical fiber. Users independently and randomly grab sections of the chaotic waveform, separate into tag and key parts, and exchange tag parts to identify the common key parts which can be used to make secure keys. The frequency of trigger pulses in the waveform is used to control the security of the scheme which depends on the small probability of a third party coincidentally acquiring samples acquired by two other users. (C) 2003 American Institute of Physics.