Design And Simulation Of Key Management System For Railway Safety Communication

Chinese Train Control System (CTCS)-3 train control system is a kind of Communication Based Train Control System, which uses Railway Signal Safety Protocol-Ⅱ (RSSP-Ⅱ) protocol to ensure the security of communication between on-board equipment and ground equipment. RSSP-Ⅱ protocol stipulates that the identification and authentication can confirm the identity of both sides of communication.In order to ensure the integrity of the protection, this process should be conducted between the times that peer entity starting new effective conversation. However, the realization of this process requires authentication key, which determines that key management system is of great significance to secure communication between equipment of CTCS-3 train control system.According to the CTCS specification, RSSP-II protocol, and offline key management function interface specification, this thesis designs and realizes the key management server, and it can communicate with the laboratory existing railway signal simulation test platform which is used for information security communication protocol. The thesis main work is as follows:First, the thesis analyzed the CTCS specification, RSSP-Ⅱ protocol and offline key management function interface specification, which provided theoretical bases for the whole structure of this system. Due to system’s high requirement of random number, this thesis used an improved cross coupled map lattices to design a kind of true random number generator based on the mouse. The test results indicate that various performance indexes of improved model are better than the unimproved one. We also test the performance of the random numbers which generated by the true random generator, test results matched the 15 kinds of random testing indexes suggested by NIST SP800-22 and four random number test indexes suggested by NIST FIPS 140-2.Then, according to the relevant protocol specification and the thesis analyzed system’s requirements, we chose Client/Server structure as the overall structure of the system, and designed system in detailed. To ensure that the client and server could receive and parse massage, this thesis designed communication protocol between client and server.Finally, with VC++6.0 as development platform, it programmed system and tested system’s function. Test results show that the key management system realizes the function of key management, and it satisfies the system’s requirements.