Authentication process based on the synchronization of chaotic oscillator networks

With regard to secure communication or filtered access purposes, this paper presents an authentication process which involves the controlled (i.e. forced) synchronization of several continuous-time chaotic systems. This process is mainly based on setting up a ring network of three unidirectionally coupled Chuapsilas oscillators, where one chaotic subsystem represents the ldquoidentification keyrdquo (i.e. a claimed identity to be authenticated) while the two others can be viewed as locking/unlocking devices. The proposed authentication protocol then consists in performing a kind of tripartite handshaking procedure1 by means of synchronizing some state trajectories of interest with respect to a particular chronology. To deal with such an objective and temporal constraints, this paper investigates the use of sliding mode controllers to drive each chaotic subsystem. Thus, after describing the authentication process, this paper focuses on the controlled, partial synchronization of the three subsystems. Then two illustrative examples with right and wrong chaotic ldquoidentification keysrdquo are presented.