In this contribution we present the secure transmission of several signals based on chaos synchronization. The idea is to transmit as many signals as system states in secure manner. It is required that the transmitted chaotic attractor does not change in order to maintain the security level. The method is based on the Multiple-Input and Multiple-Output (MIMO) control theory for nonlinear systems. Moreover the Transmitter and Receiver synchronizes in spite of the uncertainties in both systems. In this sense the secure communication scheme is robust. We illustrate the result using synchronization of similar systems
