Performance evaluation and verification of communication protocol for railway signaling systems

As long as railway signaling systems is digitalized, communication link is getting more important as a result of variety of communication links, such as links for interface between each signaling are replaced by digital communication channels. However, the communication links for current railroad signaling have some problems in Korea. At first, the maintenance is difficult because protocols for interface are applied differently at the each manufacturer. Also, communication protocols, such as structure, byte format, and error correction method, have a little non-logical part, which threatens safety. In order to solve this problem, the standard communication verified by using formal method is required. After designing new protocol for railway signaling, this paper analyzed the designed protocol's structure and performance through simulation. Also, as a very important part in the development of protocol, this paper specified the designed protocol in Labeled Transition System (LTS) with model check method, and verified safety and liveness proprieties of the designed protocol. Therefore, it is expected that the safety, reliability, and efficiency of maintenance for the railway signaling systems will be increased by using the newly designed communication protocol in Korea. (C) 2004 Elsevier B.V. All rights reserved.