Abstract: An Ethernet switch has a header device with a crossbar device and a number of downstream interface modules with a first number of a series of ports and a second number of a series of ports, respectively, such that in each case the same one in the series of the first number of ports is connected to a switching control unit coupled to an interface device, and the further ports in the series of the first number of ports are connected to a port in the second number of the series of ports via respective data lines routed in cascade form.

Abstract: An Ethernet switch has a header device with a crossbar device and a number of downstream interface modules with a first number of a series of ports and a second number of a series of ports, respectively, such that in each case the same one in the series of the first number of ports is connected to a switching control unit coupled to an interface device, and the further ports in the series of the first number of ports are connected to a port in the second number of the series of ports via respective data lines routed in cascade form.

Abstract: The invention realizes high speed data transmission, as known from the Fast Ethernet, with fieldbus systems in the field of industrial automation. A suitable fieldbus component includes a data link layer, which operates with a fieldbus protocol, and a physical layer, which is constituted for high speed data transmission. There are also provided an interface, which connects the data link layer and the physical layer, and a layer for matching the data link layer to the physical layer.

Abstract: An arrangement for coupling bus subscribers and bus masters in a master-slave bus system which has a ring topology and in which the bus subscribers are coupled actively without subscriber addresses and in which the bus subscribers are each allocated a bypass element which causes a brief interruption in data interchange and makes the bus master to interrogate addresses for restructuring purposes when the associated slave subscriber is decoupled and coupled. The bypass elements each have an address store which can be selected only in the event of the address interrogation and which is inactive during data interchange.