Verified systems by composition from verified components

Abstract

This paper presents an approach to integration of model checking into component-based development of software systems. This approach assists in development of highly reliable component-based software systems and reduces the complexity of verifying these systems by utilizing their compositional structures. Temporal properties of a software component are specified, verified, and packaged with the component. Selection of a component for reuse considers not only its functionality but also its temporal properties. When a component is composed from other components, a property of the component is verified on an abstraction of the component. The abstraction is constructed from environment assumptions of the component and verified properties of its sub-components. A general component model that enables component verification is defined. Component verification is discussed in the context of the instantiation of the general component model on an Asynchronous Interleaving Message-passing computation model. This approach has been applied to improve reliability of instances of TinyOS, a component-based run-time system for networked sensors. A case study on TinyOS is included, which illustrates the applicability of this approach, the detection of a bug, and the reduction in model checking complexity.