On the transition from design time to runtime model-based assurance cases

System assurance cases are used to demonstrate confidence in system properties of interest (e.g. safety and/or security). They are key artefacts for safety and/or security acceptance for systems before they become operational. Cyber-Physical Systems (CPS) form a new technological frontier for their vast economic and societal potentials in various domains. CPS are often safety-critical systems. Thus, their safety and/or security need to be assured using system assurance cases. However, due to the open and adaptive nature of CPS, the need for system assurance at runtime is imperative. Therefore, assurance cases are expected to be exchanged, integrated and verified at runtime to ensure the dependability of CPS when they intend to execute a cooperative behaviour. In this position paper, we identify the importance of model-based system assurance, we discuss the paradigm shift of assurance cases from being manually created artefacts to (semi-)automatically created models. We discuss the application of model-based assurance cases in ensuring the dependability of CPS.