UIC 917-4:2004-10

This leaflet defines procedures for the communication between staff who are responsible for keeping the international data exchange for railway purposes operational. It is recommended that a Network Telecommunication Centre that is continuously operational should be set up in order to simplify communication. Formal procedures, which aim to repair faults as soon as possible, are based on the exchange of the standardized forms defined in the Leaflet. Every message shall be acknowledged by the recipient. In order to avoid language barriers, the number codes have been defined for different transmission equipment and situations. Special care has been given to the definition of physical line numbering (not to be confused with the data network addressing scheme defined in UIC Leaflet 917-1) and reference numbers of events.