The Industrial Ethernet Bridge and Firewall Wall IE from Systeme Helmholz easily integrates machine networks into the higher-level production network. A packet filter protects the networks from unauthorized access. If identical IP address ranges are to be implemented, the device acts as a bridge. The router operating mode is used to forward data traffic between different IPv4 networks. It enables address translation using NAT and uses packet filters to restrict access to the automation network behind it. In bridge operating mode, the device acts as a layer 2 switch. In contrast to normal switches, however, packet filtering is also possible in this operating mode. This makes it possible to restrict access to individual areas of a network without having to use different networks. The device is robust enough for industrial use and is suitable for top-hat rail mounting.