Design of Adaptive Security Mechanisms for Real-Time Embedded Systems

Introducing security features in a system is not free and brings along its costs and impacts. Considering this fact is essential in the design of real-time embedded systems which have limited resources. To ensure correct design of these systems, it is important to also take into account impacts of security features on other non-functional requirements, such as performance and energy consumption. Therefore, it is necessary to perform trade-off analysis among non-functional requirements to establish balance among them. In this paper, we target the timing requirements of real-time embedded systems, and introduce an approach for choosing appropriate encryption algorithms at runtime, to achieve satisfaction of timing requirements in an adaptive way, by monitoring and keeping a log of their behaviors. The approach enables the system to adopt a less or more time consuming (but presumably stronger) encryption algorithm, based on the feedback on previous executions of encryption processes. This is particularly important for systems with high degree of complexity which are hard to analyze statistically.