Principles and requirements of the "Technical terms of delivery for roadside outstations" standard in Germany (TLS) for the system of automatic traffic counting and traffic control by variable message signs are described. The article outlines the work completed to date for equipment to be used for traffic counting and traffic control. Emphasis is laid on compatibility within the TLS system which is guaranteed by standardised communication interfaces between all system components. This means an open market for procurement of equipment as well as for ease of expansion. Further development with respect to pan-European data exchange is considered. The objectives for standardisation on the European level in this field are to come to an open market in Europe for equipment and to facilitate "data exchange" across borders. It needs defining data contents, a data exchange format between traffic control centres (TCC) and creating an adequate interface in the system defined by the TLS standard.
Abstract