Modeling Resilience in System of Systems Architecture

System of Systems (SoS) can be represented by the SoS architecture which defines the constituent systems and their interfaces. SoS delivers capabilities beyond what the systems working independently can provide. Resiliency of the SoS is becoming increasingly more important and necessary for mission success. Resiliency can be defined as the ability of the SoS architecture to defend against emerging threats. This defense means adapting the SoS architecture to handle the new threat. As a new threat is uncovered, the SoS architecture evolves to a new SoS architecture resilient to the new threat. This paper presents a novel approach to modeling SoS resilience using the SoS architecture as represented in Department of Defense Architecture Framework (DoDAF) views. DoDAF views are required for US DoD programs and are a way of common communication among stakeholders. This modeling approach uses an executable agent-based model of the SoS that includes the SoS architecture and possible threats. The initial SoS architecture is taken from the appropriate DoDAF views. The modeling approach introduces a threat and then adapts the SoS architecture to handle the threat. In this way, resiliency is increased. Finally, the DoDAF views are updated to reflect the newly adapted SoS architecture.