A Supplemental Notation of GSN Aiming for Dealing with Changes of Assurance Cases

An assurance case is a document containing arguments about risk-related issues on a system and regarded as an effective means to achieve open systems dependability. This paper proposes a notation of an assurance case to deal with changes of a system which can pose challenges to an established assurance case. The proposed notation is based on GSN and the presented case study suggests that the notation can make change-management of assurance cases easier. We also show that a GSN with a confidence map can be expressed by the proposed notation.