Availability Assessment of Embedded Systems with Security Vulnerabilities

The paper discusses modeling assessment aspects of incorporating security into an embedded system. The essential assumption in the approach and the model we propose is that a security breach may cause degradation of the service and ultimately a failure. The security model concentrates on the system´s interaction with the environment via a communication channel. The cooperative adaptive cruise control (CACC) system is used as a case study. The results of the study obtained for availability assessment due to security lapses show that a modeling technique may be used to evaluate the need for appropriate mitigation mechanisms allowing the system to withstand the attacks still assuring desired level of availability.