The road traffic simulation is an important tool for analysis and control of road traffic networks. In order to be able to simulate very large traffic networks in a reasonable time, it is possible to use a distributed computing environment. There, the combined power of multiple interconnected computers is utilized. During the adaptation of the simulation for the distributed environment, it is necessary to divide the traffic network into sub-networks, which are then simulated on particular nodes of the distributed computer. The load-balancing of the sub-networks and the communication between them are two key issues.