Towards a QoS Modeling and Modularization Framework for Component-based Systems

Current domain-specific modeling (DSM) frameworks for designing component-based systems provide modeling support for system's structural as well as non-functional or quality of service (QoS) concerns. However, the focus of such frameworks on system's non-functional concerns is an after-thought and their support is at best adhoc. Further, such frameworks lack strong decoupling between the modeling of the system's structural composition and their QoS requirements. This lack of QoS modularization limits (1) reusability of such frameworks, (2) ease of their maintenance when new non-functional characteristics are added, and (3) independent evolution of the modeling frameworks along both the structural and non-functional dimensions. This paper describes Component QoS modeling language (CQML), which is a reusable, extensible, and platform-independent QoS Modeling Language that provides strong separation between the structural and non-functional dimensions. CQML supports independent evolution of structural metamodel of composition modeling languages as well as QoS metamodel. To evaluate, we superimpose CQML on a purely structural modeling language and automatically generate, configure, and deploy componentbased fault-monitoring infrastructure using aspect-oriented modeling (AOM) techniques.