Public-channel cryptography based on mutual chaos pass filters.
We study the mutual coupling of chaotic lasers and observe both experimentally and in numeric simulations that there exists a regime of parameters for which two mutually coupled chaotic lasers establish isochronal synchronization, while a third laser coupled unidirectionally to one of the pair does not synchronize. We then propose a cryptographic scheme, based on the advantage of mutual coupling over unidirectional coupling, where all the parameters of the system are public knowledge. We numerically demonstrate that in such a scheme the two communicating lasers can add a message signal (compressed binary message) to the transmitted coupling signal and recover the message in both directions with high fidelity by using a mutual chaos pass filter procedure. An attacker, however, fails to recover an errorless message even if he amplifies the coupling signal.
Klein
Einat
E
Department of Physics, Bar-Ilan University, Ramat-Gan, 52900 Israel.
Gross
Noam
N
Kopelowitz
Evi
E
Rosenbluh
Michael
M
Khaykovich
Lev
L
Kinzel
Wolfgang
W
Kanter
Ido
I