Evaluating requirements of high precision time synchronisation protocols using simulation

High precision time synchronisation protocols are used in distributed real-time systems such as trains, planes, cars or industrial installations. In time-triggered systems, with a coordinated time division multiple access media allocation strategy, the achievable precision of time synchronisation among sending participants determines the quality of communication and the available bandwidth. The simulation of time synchronisation protocols allows to find problems at the earliest time – in general, during the design and configuration – of a synchronised distributed system. In this work we show a concept for the simulation of distributed real-time synchronisation protocols that uses discrete event-based simulation. Our model for the OMNeT++ Framework is adaptable and thus allows for providing highly accurate results or fast simulations. The precise simulation of a real-time synchronisation protocol usually consumes considerable simulation time. This paper presents an approach to speed up accurate simulation, based on recordings of previous runs. We evaluate typical real-world use cases for the introduced concept by simulating the AS6802 standard for time synchronisation. Our results show that the simulation can help to reduce the effort of determining configuration parameters for clock synchronisation protocols. We further quantify the performance increase of our evolutionary approach.