Linux Security for Beginners - Configuring a typical Router based Firewall

Let's assume you have a wireless base station, router or DSL/Cable modem that has a built in firewall. The management interface for these devices is typically accessed via your favorite web browser. For example Microsoft sell a wireless base station (the MN-500) that you access by going to 192.168.2.1 in your browser. The Linksys WCG routers use 192.168.0.1 while the Linksys WRT range of routers are accessed via the 192.168.0.1 IP address. Check the documentation for your device to find the correct IP address.