Orthogonal Fault Tolerance for Dynamically Adaptive Systems
This addresses dependability challenges in systems that adapt to user needs and environments, but it is incremental as it builds on existing fault tolerance and verification methods.
The paper tackles the feature interaction problem in dynamically adaptive systems by proposing an orthogonal fault tolerance model to manage multiple fault tolerance mechanisms, using state machine semantics and the NuSMV tool for simulation and verification.
In dynamic systems that adapt to users' needs and changing environments, dependability needs cannot be avoided. This paper proposes an orthogonal fault tolerance model as a means to manage and reason about multiple fault tolerance mechanisms that co-exist in dynamically adaptive systems. One of the key challenges associated with dynamically evolving fault tolerance needs is the feature interaction problem arising from the integration of fault tolerance features. The proposed approach provides a separation of fault tolerance concerns to study the effects of integrated fault tolerance on the system. This approach uses state machine and operational semantics to reason about these interactions and inconsistencies. The proposed approach is supported by the tool NuSMV to simulate and verify the state machines against logic statements.