Secure Optical Communication Based on Cluster Chaos Synchronization in Semiconductor Lasers Network

We propose and numerically demonstrate a secure optical communication scheme in a small-world semiconductor lasers network based on cluster chaos synchronization and false-message scrambling. According to the symmetries of network, the semiconductor lasers are divided into sets of heterogeneous coupled clusters. The properties of cluster chaos synchronization, the performance and security of optical chaotic communication, as well as the influence of false message on the synchronization of clusters are systematically investigated. It is demonstrated that, by properly setting the parameters of the lasers network, high-quality chaos synchronization can be achieved between the intra-cluster lasers, whereas incoherent states are observed between inter-cluster lasers. Moreover, by inserting false messages into the inter-cluster couplings, the privacy of chaotic carriers transmitted over the inter-cluster public links can be significantly enhanced, as such secure bidirectional communication among intra-cluster lasers is achievable with a message bit rate of several Gbit/s. Compared with the conventional point-to-point communication systems, the proposed scheme supports multipoint-to-multipoint secure communications.