Method for operating a communiction system for trains

Address assignment is carried out at the control bus system. Train composition regarding number, succession and insertion direction of wagons, i.e. carriages and/or goods wagons, is ascertained. In addition the fixed computer nodes forming part of the control system and associated with the wagons, are registered. The information is relayed over the information bus and used to form dynamically-modified addresses for the nodes, which are used in the train information bus system.