MLCCA — Multi-Level Composability Check Architecture for dependable communication over heterogeneous networks

During the design of complex networked systems, it is crucial to ensure the composability of the deployed applications and network protocols. Special care has to be taken to provide non-functional requirements like bandwidth and latency. Existing solutions only tackle this problem during the design phase; later refactoring or added components are not covered, potentially causing QoS violations. We propose MLCCA, a multi-level architecture which complements the design-time composability checks with additional automatic checks performed at compile-time and at run-time. The required infrastructure is embedded into our communication middleware FAMOUSO, making it transparent to application developers. The architecture has been evaluated in a tele-operated mobile robot case study. If the QoS attributes could not be fulfilled due to refactoring or changed conditions, no communication was allowed by the middleware, ensuring that the application could enter a fail-safe state. No data was sent over insufficient channels. Thus, our combination of FAMOUSO and MLCCA enables the sustainable deployment of complex networked systems.