Generalized Synchronization of Two-Layered Complex Dynamical Networks and Its Application to Robust Chaotic Encryption

This paper proposes a robust chaotic secure encryption method based on the generalized synchronization of two-layered complex networks. Using a nonlinear mapping to realize generalized synchronization, the proposed scheme relaxes both the requirement for identical node dynamics and system parameters, which substantially raises the difficulty of reverse engineering and brute-force attacks. Meanwhile, unlike traditional chaos masking, binary information is encoded in time-varying parameter perturbations rather than in chaotic signal-domain superposition, leveraging synchronization errors induced by parameter mismatch in data transmission. The integration of static node parameters as foundational keys and dynamic binary sequences as transient keys creates a chaotic composite key space, exponentially increasing the complexity of cryptanalysis. Furthermore, the paper proposes a robust decryption scheme based on generalized synchronization between the drive network and the response network, which decrypts the information by calculating the synchronization errors of node states. Numerical simulations demonstrate that the proposed encryption scheme can effectively recover the original information in the presence of channel noise.