Using Blockchain Technology to Ensure Trustful Information Flow Monitoring in CPS

In cyber-physical systems (CPS), information flow monitoring is an essential task for detecting errors. Particularly, semantic dependencies between exchanged information play an important role. Due to emergent structure of CPS, this is not plain to accomplish but can be solved by monitoring tools. If several parties are cooperating in a CPS, there is the additional problem that all have to work together to collect those dependency information. In the event of an error, however, the responsible party may no longer want to admit that it caused the error. Therefore, the information required for the investigation must be securely stored so that all parties involved can rely on this information without having to trust the other parties. In this paper, we present our idea of how parties with different interests can cooperate in a CPS without having to trust each other in case of errors. Each party will be separately able to understand dependencies between exchanged information. For this purpose, our approach uses various decentralized storage mechanisms, we particularly also highlight the possibility of using blockchain technology.