Reliability Analysis of CTCS-3 Security Services Based on 5G-R Using Timed Colored Petri Nets

The CTCS-3 level vehicle-ground communication system based on 5G-R is a dynamic and complex distributed system, and its reliability research is of great significance for ensuring train safety and accelerating the research of the next generation railway mobile communication system. This paper proposes a layered structure for the CTCS-3 5G-R wireless communication system model using a layered Colored Petri Net (CPN), which integrates fault models such as connection loss, handover, and transmission errors, and models it using CPN Tools. This paper uses timestamp to achieve statistical analysis of data frame transmission delay, and analyzes the reliability probability of 5G-R wireless channel and the impact of data frame transmission time interval on delay. The results show that when the data frame transmission delay is less than 60 ms, the reliability probability is 99.7495%, which meets the requirements of CTCS-3. Finally, it verifies that the CTCS-3 train control system based on 5G-R can meet the requirements of real-time communication, thereby ensuring train safety.