Chaos and Encryption: Problems and Potential

A brief introduction to the history of chaos and chaotic encryption is provided. Simple circuits that oscillate chaotically are reviewed. Methods of removing the masking produced by a single chaotic oscillator are reviewed. Methods that have been proposed to produce a secure encryption scheme using chaotic oscillators are described and evaluated. Based on the knowledge that only circuits with a single nonlinear element synchronize quickly enough to allow the encryption decryption of real-time communications, and that such schemes are inherently vulnerable to return map reconstruction, it appears that chaotic encryption will not be deployed in communications systems. However, systems with multiple nonlinearities continue to show some promise