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.