Design And Research On Network Hardware Platform Based On Netfpga Industrial Ethernet Train Backbone

The development of modern train tends to more high-speed, automation and comfortable. Compared with the conventional train, more and more information are needed to be transmitted, such as state control, fault diagnosis, passenger service information, voice, video, etc. How to transfer these information more faster, reliable and accurate has become a critical issue on train equipment research.This paper based on the above problems combine with IEC61375-2-5Ed.l Electrical railways equipment-Train Communication Network-Part2-5:ETB-Ethernet Train Backbone, and built train Ethernet backbone network by Xilinx NetFPGA platform. And on the basis of the analysis of network delay model proposed and implemented two kinds of improvement measures of train backbone network. Under different background traffic, the delay time on the constructed backbone network was tested.NetFPGA modular design concept allows users can easily constructed high performance network system in this platform. Secondary development of this paper was based on the NetFPGA reference router design, what implement Ethernet data transmission and forward which agreed by IEC61375-2-5.Data type of Train Ethernet backbone network which agreed by IEC61375-2-5is802.3, what contrary to common Ethernet data type is different. So we must identify the data-type in the underlying hardware platform first, and then to deal with it. Data-type mainly include IP data, TTDP data, ARP packet and802.2LLC data. Some of IP data packets need to be forwarded, another data are submitted directly to the CPU, such as TTDP data packets are processed directly by train topology discovery protocol.Through the analysis of train backbone network delay model, this paper used Load-balancing and Data transmission by classification and different channels to reduce arrival rate to improve efficiency and certainty of the network. Based on the general design of the train backbone network, realize Load-balancing and Data transmission by classification and different channels by Verilog-HDL programming to improve the performance of the network.Finally, Load-balancing and Data transmission by classification and different channels was tested, and under different background traffic, the delay-time was tested, analysed and compared. Test results show that improvement measures can improve the network performance effectively under the condition of large amount of data. Able to meet the needs of the train backbone network transmission of large amounts of data.