Modeling and Analyzing Component-Based Distributed Railway Interlocking System with Petri Nets

Component-based Distributed Railway Interlocking System (CBDRIS) was presented recently. It is expected to reduce the development time and improve the reliability of railway interlocking systems. All interlocking devices in CBDRIS are at the same layer and there is no centralized interlocking computer. In this paper the CBDRIS is modeled with Petri Nets. We model CBDRIS in three layers: functional modules, device components which consist of functional modules, and the whole interlocking system which comprises of the device components. Considering route conflict and device conflict probabilities are key factors to route reservation success, we analyze the relations between the two conflict probabilities and route reservation success probability with the proposed approach and based on the modeling results, which is useful for system design and development.