Capturing Dependability Threats in Conceptual Modelling

Abstract

To improve the focus on security and other dependability issues it might be useful to include such concerns into mainstream diagram notations used in information systems analysis. In particular, there have been proposals introducing inverted icons to depict functionality not wanted in the system (e.g., misuse cases) or actors with malicious intent (in i* diagrams), thus addressing security issues in such notations. But there are many other modelling notations also used in early systems development, and the focus on dependability could be strengthened if these provided similar means to incorporate dependability issues. This paper looks at the possibilities for addressing dependability in information models and workflow models. To maintain visual consistency with the abovementioned proposals, it is suggested to apply inverted icons also here. In information models this can be used to represent misinformation, and in workflow models malicious or fraudulent actions attacking the business process. In both cases, inversion of icons contributes to clearly distinguishing between what is wanted in the system and what must be avoided, thus enabling a visual representation of dependability concerns.