Abstract
For the traffic control in large districts or entire cities (several hundreds of intersections) simulation is indicated. However, simulation of such a large system is nearly impossible as a consequence of restricted memory space in computers and if a reasonable degree of accuracy of the results is desired, too long simulation times. Therefore a model of traffic flow has been developed that does not look at separate vehicles, but at clusters of vehicles. It has turned out that it is possible in this model to describe in a realistic way traffic behavior at the intersections and on the roads between them.