Rule-based strategic reflection: observing and modifying behaviour at the architectural level

As software systems become larger and more complex, a relevant part of code shifts from the application domain to the management of the system´s run-time architecture (e.g., substituting components and connectors for run-time automated tuning). We propose a novel design approach for component based systems supporting architectural management in a systematic and conceptually clean way and allowing for the transparent addition of architectural management functionality to existing systems. The approach builds on the concept of reflection, extending it to the programming-in-the-large level, thus yielding architectural reflection (AR). The paper focuses on one aspect of AR, namely the monitoring and dynamic modification of the system´s overall control structure (strategic reflection), which allows the behaviour of a system to be monitored and adjusted without modifying the system itself