Analysis And Design Of Safety Communication Simulator On Computer Interlocking Based On RSSP-I Protocol

With the implementation of new technologies in modern communication and microelectronics,and the wider application of communication-based train operation control systems,network communication security in railway signaling systems has gradually become a key issue to be solved urgently.After the station computer interlocking system is connected to the safety data network of the railway signal system of the passenger dedicated line,the RSSP-I or RSSP-II railway safety communication protocol is usually used to realize the safety data transmission and information sharing with the multiple train control system equipment of the passenger station.The correctness and reliability of the safety communication protocol will directly affect the operation effect of the computer interlocking system.This thesis summarizes the functions of the station computer interlocking system,the test classification and test environment of the interlocking system,and analyzes the computer interlocking system and other equipment from the classification of the transmission system and the possible threats in the communication process of different transmission systems.Two RSSP safety communication protocols used in communication.This thesis focuses on the research of the RSSP-I safety communication protocol used in the communication interface between the station computer interlocking system and the adjacent station interlocking system,and completes the design and test of the station interlocking safety communication simulator on this basis.Firstly,using Visual Studio 2013 platform,according to the communication interface specification between railway station computer interlocks,referring to the safety communication system architecture,a layered design method is used to develop a station interlocking safety communication simulator software based on RSSP-I protocol.For the application layer,it is mainly divided into the design of the main interface and the design of the safety user data message;the design of the security function module is composed of the initialization of the module,the sending and receiving processing of the message,the clock update,etc.,and the security involved in it is introduced in detail.The principle and design process of the algorithm;the bottom layer of the designed communication function module adopts the connectionless UDP transmission to realize the communication with the external equipment.At the same time,a fault injection module is added to the station interlocking safety communication simulator,and a total of 9 faults are designed to simulate the possible threats in real network communication.Then,on the basis of completing the development of the RSSP-I protocol automatic analysis script,the software of the station interlocking safety communication simulator is tested.First,the interoperability test is carried out to test the security application data interaction function based on the RSSP-I protocol,and it is verified that the communication system based on the RSSP-I protocol can resist the relevant threats and risks in the transmission process.In addition,the station interlocking safety communication simulator software is tested with the real computer interlocking system,and the results show that the safety communication simulator can also be used for the communication interface test and interlocking logic inspection of the station computer interlocking system in the laboratory.Finally,the limitations and shortcomings of the two existing RSSP safety communication protocols in practical application are analyzed,and the RSSP-I protocol introduces peer entity authentication and message authentication security code calculation based on 3DES symmetric encryption algorithm.In order to expand the application scenarios of the RSSP-I protocol,so that it can resist the risk of information camouflage during the transmission process,the encrypted transmission of the security messages based on the RSSP-I protocol is implemented in the safety communication simulator.