Modeling Reactive Trust Acquisition Using State Transition Systems

Abstract

In this work-in-progress article, we propose the use of state transition systems to model and specify non-trivial real-life trust acquisition strategies, which are stateful and may dynamically adapt, depending on the particular context/situation of a truster, a trustee or an environment. The approach is exemplified with an oral examination scenario in which the kind of questions and, hence, the trust acquisition strategy can be automatically adjusted according to the performance of the examinee. We define a discrete trust metric (a "state of trust"), built on top of a continuous trust representation (Jøsang's subjective logic in our example). To specify the according trust acquisition policy as a state-transition system, we use the temporal logic cTLA.