A user must protect his network from the bugs and threats of the outside world. Firewall feature in your router ensures a user to help your network from getting attacked with malicious bugs and viruses. The SPI (Stateful Packet Inspection) within the Firewall provides major protection within your network. Sometimes a user also wants to expose his network to other networks for allowing certain types of web applications to work. A user can enable the DMZ (Demilitarized Zone) to expose a computer within the network. If you enable the DMZ in your network, the chosen system will get completely exposed to the outside world. You can do so with the help of the dlinkrouter.local window.