IEC 61375-1 and UIC 556-international standards for train communication

The communication system within a train is a central issue for train system integration. Historically, there have been numerous, proprietary and non-interoperable solutions. IEC 61375 and UIC 556 have now been issued as a set of international standards to overcome this situation: IEC 61375, the Train Communication Network (TCN), defines a communication architecture and the necessary protocols for non-vital communication on train and on vehicle level. It consists of a two-layered, hierarchical architecture to suit the needs of inter- and intra-vehicle communication. UIC 556 and the accompanying UIC codes define the operator's view on the train, the framework for the coordination of the different applications and the operational handling to ensure interoperability between vehicles from different manufacturers. This protocol suite has been successfully explored in operational test trains as well as in large number of actual running projects for DMUs, EMUs, high-speed trains, locomotives, passenger trains, suburban trains, as well as trams. It is used for new vehicles and for vehicle refurbishment. The article focuses on the TCN and UIC standards, their development and application in actual projects.