On tools for the design of system architechtures for innovative traffic information systems

To reach full scale efficiency and synergia, road traffic information and control systems have to be appropriately integrated into an overall management system which coordinates the information flow and the control decisions. The framework of this integration is provided by the system architecture for: integration of functions and subfunctions (functional layer), organisation of information flow (data flow layer), coordination of control decisions (operation layer), and interaction of physical units and components (physical layer). In this paper we present some parts of our work on system architectures along the lines of the above four layer scheme. To demonstrate the procedure, we have chosen emergency warning as an application that is an excellent but not too complex example for the RTI system which needs the framework of a well designed architecture