speed digital train coupler link 24 is connected at both ends of the train car 10 a number of communication busses links or peripherals 26 such as an rs 232 connector a multi function vehicle bus a lonworks a can bus and an integrated on board information system are connected to the control unit 22 one skilled in the art will recognize that the interface may include a gateway or conversion circuit between the lan interfaces or ethernet u2122 link and the itu g9954 multimedia high speed digital link for inter vehicle transmission additional busses links or peripherals 26 that do not support an ethernet network interface may also be connected to the lan 20 through the control unit 22 or through other interface devices the itu g9954 multimedia high speed digital link 20 provides for a wide area network wan backbone connection that implements the concept of quality of service qos to guarantee data packet delivery of sensitive propulsion and diagnostic data the lan 20 is divided into lan subsystems 28 a 28 b 28 c which are located in each car section 12 a 12 b 12 c respectively of the first train vehicle 10 similar lan subsystems may also be located in the second train vehicle 14 and connected together using the digital link 24 each lan subsystem 28 a 28 b 28 c includes a multi port ethernet u2122 network hub 30 a 30 b 30 c respectively the multi port ethernet u2122 network hubs include a number of network ports which are particularly well suited for the present invention since they reduce unnecessarily complex wiring across the articulated joints 13 that separate the car sections 12 a 12 b and 12 c in an articulated train vehicle one network segment may have a network port.