Secure random number generation using chaotic circuits

The authors show how to use a chaotic circuit as a secure random number generator and given an example using a first-order, nonuniformly sampling, digital phase-locked loop (DPLL) operating in a chaotic regime. The security of the proposed generators is estimated from the information loss property of chaotic systems. For a generator implemented using a chaotic DPLL, two important cases are considered. First, given no prior information concerning the initial conditions of a continuously running circuit, the authors establish how long one should wait after taking a bit before one can securely take another bit. Secondly, given knowledge of the initial conditions at startup (up to measurement and noise uncertainty), they show how long one should wait before starting the bit sampling