Application Of Subway Communication Based On Industrial Ethernet Technology

At present, the domestic urban rail traffic is in the direction of development of network and large capacity, its communication electromechanical system includes more than ten subsystems, each subsystem is independent but interchanging information. SDH as main transmission network is the traditional communication mode, each subsystem in SDH cedes independent channels in communication. However, the metro monitor system is mainly with sudden data stream, while SDH is for fixed-length bandwidth voice communication service, which can't meet the subway system's massive sudden data flow. Ethernet technology is mainly used for data communication, but the collision domain mechanism and lots of broadcast message bring the problem of broadcast storm, which makes many experts doubt with Ethernet as a backbone network. The research of industrial Ethernet is more in control layer at home and abroad, which solves the problems of the control network real-time and redundancy loop back, etc. As to the issue on the industrial Ethernet as backbone network communication, both at home and abroad are rate.Combining with the application requirement of Tianjin metro transmission system, and from technology advanced, the feasibility of the project, cost comparison, schedule and quality control system, the paper has studied the application solutions of industrial Ethernet technology in the subway transmission project. The solutions are taking the net of ten thousand Ethernet as the subway backbone communication, and improve the network utilization by dynamic bandwidth allocation, thus solved the traditional SDH solutions of bandwidth problem and real-time problem. And the solutions complete the isolation of each subsystem by VLAN which ensures each system can operate independently, and meet the two-way requirements between the subsystem comprehensive interconnected communication and independent operation by reducing the broadcast domain, thus improving the network security. What's more, the solutions solve the broadcast storm caused by Ethernet loop back by the means of virtual breakpoint, and achieve the link of fault protection based on link loop back protection, thus improving the system reliability and usability. Through the above study, the paper has resolved the key issues on data emergency communication of transmission system, redundancy protection, subsystem isolation, control system with real-time and network security, etc. Moreover, based on the research content, the paper has built the simulation system, and has done a lot of experiment results show that the system scheme is feasible, in system redundancy, real-time, security and network management function, etc., all conform to expected results. The research has started in Tianjin metro for actual implementation, the success of the project for the domestic subway built to a technique level advanced, safe and reliable, efficient operation of people's livelihood project is of great significance.