Fast Ethernet Train Backbone Node 

Train Backbone Node



  • Compliant with IEC 61375 standard
  • Compliant with IEC 61375-2-3 standard
  • 4 x FE switched ports + 1 x FE routed port
  • 2 bypasses
  • R-NAT (railway 1:1 NAT)
  • Router Redundancy Protocol
  • Dynamic routing following train inauguration
  • TTDP protocol
  • Full communication profile
  • TRDP protocol
  • Compliant with EN 50155 standard
  • Compliant with EN 45545 standard
  • Extended temperature range -40 °C / +85 °C

VDS Rail's Fast Ethernet Train Backbone Node (TBN) is used when two or more trains need to be connected together. The TBN has been specially designed to meet the requirements specified by IEC standards for the train Ethernet backbone network (ETBN nodes). 

Double switched backbone lines protected by a bypass relay ensure high levels of fault tolerance also in the case of a power failure. A couple of TBN can be used together using an active/passive redundant configuration to obtain the maximum level of protection. 

Designed to operate in harsh environmental conditions typical of rolling stock applications, the TBN can be powered from 24 Vdc to 110 Vdc nominal voltage. Fully EN50155 compliant, it provides the highest level of reliability and robustness required by the railway industry.

Backbone side

Through the TTDP protocol, IEC Train inauguration procedure is fully supported. Routing and address translation rules (R-NAT) for multiple consist networks interconnections are automatically defined during train inauguration as well as TRDP interface. Full communication compliance with TRDP End Devices, as well as with IEC 61375-3-2 TCN communcation profile is ensured.

Consist side

On the consist side, a routed port is available to connect the backbone to the consist network. VDS Tools provide automatic main configuration and continuous monitoring giving the customer a way to reduce commissioning and maintenance costs.

Main technical specifications

  • IEEE Standard Physical layer :IEEE 802.3 10BASE-T, IEEE 802.3u 100BASE-TX
  • IPv4 protocol supported (IPv6 protocol ready)
  • Spanning tree (STP 802.1D) and Rapid Spanning Tree (RSTP 802.1w)
  • Link aggregation protocol (LACP 802.3ad)
  • Up to 4096 802.1Q VLANs
  • DHCP option 82 handling
  • IGMP versions 1, 2 and 3 snooping
  • SNMP v1, v2c, v3 device management
  • Static IPv4 unicast and multicast routing
  • OSPF and RIP dynamic routing protocols
  • Network Address Translation (SNAT, DNAT and R-NAT)
  • Packets filtering
  • Router Redundancy Protocol
  • Dynamic routing following train inauguration
  • Train-wide standard multicast routing  

Physical data

  • Connector type: M12
  • Power supply: From 24 Vdc up to 110 Vdc
  • Power supply class: S2, according to EN-50155
  • Power consuption: 22 W max
  • Overall dimensions: 207 x 184 x 51 mm
  • Weight: 2,0 Kg
  • Operating temperature: From -40°C up to +70 °C according to EN-50155
  • Storage temperature: From -40°C up to +85°C
  • Degree of protection: IP40, IP54; IP65

Main approvals/compliance

  • EN 50155: Railway Applications (Electronic equipement used on rolling stock)
  • EN 61373: Shock & Vibration
  • EN 45545: Fire & Smoke
  • IEEE 802.3: Ethernet Network Standard