Modeling Approaches for System-of-Systems Dynamic Architecture: Overview, Taxonomy and Future Prospects

System-of-Systems (SoS) result from the collaboration of independent Constituent Systems (CSs), connected in a certain configuration known as an architectural configuration, to achieve a common mission. The architectural configuration may change as new CS may join SoS and/or existing CS may leave SoS at runtime. These architectural configuration changes have affect on the overall system quality attributes (i.e. performance, security and reliability). Therefore, modelling SoS architecture is a challenging task as CSs and the possible architectural configurations are not entirely known at design time. Architectural description languages (ADLs) have been proposed and used to deal with SoS dynamic architecture. However, we still envision gaps to be bridged and challenges to be addressed in the forthcoming years. This paper outline a taxonomy for modeling SoS and provides a broad discussion on the state-of-the-art modeling notations to model and analyze SoS architectural configuration. An SoS case is presented to explain the impact of architectural configurational changes on the SoS properties. Besides, we also discuss challenges and future directions to be overcome in the forthcoming years.