A security system (20) includes a plurality of sensors (22-26) that provide an indication of a security condition to a corresponding plurality of microcontrollers (32-36). Each microcontroller communicates information regarding the security condition to a central control (40). The communications from the microcontroller include using an elliptical public key encryption for protecting a key associated with the security condition information. In a disclosed example, the security condition information is encrypted using a symmetrical encryption technique.