Using a Redundant Ethernet Network to Realize Safe Railway Transport
The He-Wu railway is a part of China's Passenger Dedicated Line (PDL), which is the biggest network of high-speed railways in China. The Ethernet-based signal control system that serves the entire rail line provides a centralized monitoring system for real-time operation with redundancy for non-stop operation and remote control services. Since railway stations are often separated by upwards of 100 kilometers, using long-haul transmission fiber Ethernet was the best way to offer instant connectivity. In order to communicate with other high-speed rail lines, the customer wanted to use a Layer 3 switch so that future upgrades could implement cross-subnet communications.
• Open source Ethernet-based backbone network to handle the complexities of daily operation
• Redundant network topologies for enhanced reliability and continuous network transmission
• Optical fiber connections permit extended transmission over longer distances and immunity to electromagnetic noise
• Layer 3 switching capability for better interconnection between railway subnets
• Industrial-level rugged products with high MTBF and extreme temperature ranges
The He-Wu railway has communication stations located every 20 km, and each station has two traffic signal controllers that connect simultaneously to two of Moxa's EDS-508A series industrial managed Ethernet switches. Since communication stations are separated by 20 kilometers, the railway uses the EDS-508A-SS-SC single-mode fiber model to extend the data transmission distance, and relies on its industrial rugged design to survive the harsh railway environment. The two Ethernet switches in each station are grouped with switches from other stations to form a dual redundant ring topology that stretches across the entire rail line. The dual ring network architecture provides maximum redundancy with minimum system downtime.
Furthermore, all of the railway information is supervised through a central computer at a server farm in Hefei station. Moxa's EDS-SNMP OPC server software provides the connectivity needed to integrate existing OPC enabled HMI/SCADA systems with a complete system that monitors remote network traffic. In order to allow interconnection with other rail lines, the system uses the Layer 3 routing functions of Moxa's EDS-828 Layer 3 Gigabit modular Ethernet switch. With its optimized routing performance, the EDS-828 can easily bridge two railway subnets and segment the network to avoid the influence of broadcast storms between different railway subnets and increase network efficiency.
• Moxa Turbo Ring supports super fast media redundancy with a recovery time under 20 ms, providing reliable and stable data transmission over the entire railway monitoring system.
• The single-mode fiber models ensure long, continuous transmission and noise immunity.
• The EDS-828 industrial Layer 3 Ethernet switch provides data transmission capability between different railway subnets.
• Moxa's industrial Ethernet switch solutions with rugged design, high MTBF, fan-less operation, and 5-year warranty are ideal for extreme and hazardous railway environments.
• Moxa's managed Ethernet switch family offers the most comprehensive features for superior network management and security, including QoS, IGMP snooping/GMRP, VLAN, LACP, RMON, SNMP V1/V2c/V3, IEEE 802.1X, HTTPS, and SSH.
• Redundant ring network technology, Turbo Ring (recovery time < 20 ms) or RSTP/STP
• Single-mode models with long haul transmission of up to 80 km
• Works with Moxa EDS-SNMP OPC Server Pro to integrate SNMP devices with OPC compatible systems
• Supports static or dynamic routing functions
• Gigabit Turbo Ring and RSTP/STP for Ethernet redundancy
• Proven intelligent management and advanced security features
See More Real World Applications
Moxa’s solutions are deployed in major railway systems across Europe, the US, and Asia, and can be found in passenger information systems (PIS), automatic train control (ATC), automatic train operations (ATO), automatic train supervision (ATS), and CCTV systems. For more information, please click on the icon to download the railway success stories.