Embedding Non-Compliant Nodes into the Information Flow Monitor by Dependency Modeling

Observing semantic dependencies in large and heterogeneous networks is a critical task, since it is quite difficult to find the actual source of a malfunction in the case of an error. Dependencies might exist between many network nodes and among multiple hops in paths. If those dependency structures are unknown, debugging errors gets quite difficult. Since CPS and other large networks change at runtime and consists of custom software and hardware, as well as components off-the-shelf, it is necessary to be able to not only include own components in approaches to detect dependencies between nodes. In this paper we present an extension to the Information Flow Monitor approach. Our goal is that this approach should be able to handle unalterable blackbox nodes. This is quite challenging, since the IFM originally requires each network node to be compliant with the IFM protocol.