Safety-Critical Adaptation in Self-Adaptive Systems
This work addresses safety concerns in self-adaptive systems for domains like critical infrastructure, but it is incremental as it builds on existing studies without introducing new methods or data.
The paper tackles the problem of defining and classifying safety-critical adaptations in self-adaptive systems, proposing a taxonomy based on impact on safety and safety case criteria, illustrated with a water heating system example.
Modern systems are designed to operate in increasingly variable and uncertain environments. Not only are these environments complex, in the sense that they contain a tremendous number of variables, but they also change over time. Systems must be able to adjust their behaviour at run-time to manage these uncertainties. These self-adaptive systems have been studied extensively. This paper proposes a definition of a safety-critical self-adaptive system and then describes a taxonomy for classifying adaptations into different types based on their impact on the system's safety and the system's safety case. The taxonomy expresses criteria for classification and then describes specific criteria that the safety case for a self-adaptive system must satisfy, depending on the type of adaptations performed. Each type in the taxonomy is illustrated using the example of a safety-critical self-adaptive water heating system.