With the advent of the Internet of Things (IoT), many domestic devices have been equipped with information technology. By connecting IoT devices with each other and with the Internet, Smart Home installations exist that allow the automation of complex household tasks. A popular example is Google Nest that controls cooling, heating and home security. However, Smart Home users are tempted to neglect that such IoT devices pose IT-Security risks. Examples like the Mirai malware have already shown that insecure IoT devices can be used for large-scale network attacks. Thus, it is important to adapt security approaches to Smart Home installations. In this paper, we introduce FANE, our concept for a Firewall AppliaNcE for Smart Home installations. FANE makes a few realistic assumptions on the network segmentation and the communication profile of IoT devices. This allows FANE to learn firewall rules automatically. Our prototypical implementation indicates that FANE can secure a wide range of IoT devices without requiring network-security expertise from the Smart Home user.