Achieving IoT Devices Secure Sharing in Multi-User Smart Space

Multiple users often share their Internet of Things (IoT) devices in a smart space. However, existing IoT systems do not support IoT sharing between multiple users or take into account the security risks associated with using shared devices. We address this problem by proposing a new multi-user IoT Secure Sharing (IoTSS) system supported by a newly designed sharing policy language. Our approach treats the policies as constraints in the context of an optimisation problem to fulfil user activities using the least vulnerable devices. We show how IoT sharing can be transformed into an equivalent Integer Linear Programming (ILP) problem, which can be solved efficiently and effectively by off-the-shelf Integer ILP solvers. To study the practical feasibility of IoTSS, we have implemented a proof-of-concept proxy-based prototype for the popularly used Mozilla WebThings Gateway. We found that the proxy service can achieve policies enforcement without incurring statistically significant time overhead.