Semi-formal and formal interface specification for system of systems architecture

The independence of the constituent systems of a system of systems presents a key challenge to the discipline of system of systems (SoS) engineering. The fact that constituent systems can and do function independently of the SoS means that engineers of a constituent system cannot rely on the behaviour of other constituent systems. This paper advocates a model-based approach to SoS engineering that requires the interfaces to constituent systems to be specified. We propose an use of an interface design pattern for interface specification that uses the industry standard notation, SysML.We also indicate a translation of these specifications to a formal notation, CML, in order to extend the range of analytic techniques available to the SoS engineer.