Abstract: A circuit arrangement for a switching system having microprocessors for decentralized execution of switch-oriented jobs is provided wherein a separate microprocessor, autonomously functional for its jobs, is provided in a network level for the connection of a respective class of connection lines with specific and identical transmission properties and in a switching level for the connection of devices respectively provided for executing specific and identical switching tasks and services. All microprocessors are connected with one another by way of a common data bus, whereby the transmission of messages in the transmitting and receiving directions between the microprocessors occurs in the form of information blocks provided with address information.