Cryptographic requirements for chaotic secure communications

In recent years, a great amount of secure communications systems based on chaotic synchronization have been published. Most of the proposed schemes fail to explain a number of features of fundamental importance to all cryptosystems, such as implementation details, or key definition, characterization, and generation. As a consequence, the proposed ciphers are difficult to realize in practice with a reasonable degree of security. Likewise, they are seldom accompanied by a security analysis. Thus, it is hard for the reader to have a hint about their security and performance. In this work we provide a set of guidelines that every new cryptosystem would benefit from adhering to. The proposed guidelines address these two main gaps, i.e., correct key management and security analysis, among other topics, to help new cryptosystems be presented in a more rigorous cryptographic way. Also some recommendations are made regarding some practical aspects of communications, such as implementation, channel noise, limited bandwith, and attenuation.