Routers have several protection mechanisms that prevent us from external attacks. The opening of ports must be manual and towards a single device, in addition to using a firewall to prevent undue access. However, there is a way to disable those functions to expose our router. What advantages and disadvantages does it have?
The firewall that integrates our router is in charge of filtering the network traffic that enters and leaves our connection. For this, a series of rules are established, through which it is determined whether or not a request is accepted. There are devices such as computers that already integrate a firewall, but there are others, such as a printer, that do not. Therefore, a router must protect all connections.
DMZ: isolated zones in our local network
However, there are situations where those protections can cause us problems. There is therefore called the DMZ, short for Demilitarized Zone (Demilitarized Zone). This zone is located between the internal network of a home or company and an external network, usually the rest of the Internet.
The advantage of this is that, through the firewall, we can generate an isolated zone in our network without protection . In this way, it is limited perimeter, and if an attacker manages to access it, he will not be able to reach the rest of the local network and compromise the rest of the devices that we have connected.
And what advantages can this have to play? Well, quite a few. By creating a DMZ, we can allow a computer or a console to access the Internet without going through the router’s port filter or NAT. With this, we have a faster and more direct connection that guarantees that we will not have problems connecting to a server, or for someone to connect to our network remotely.
Routers use ports to limit the number of connections that can reach our network, as well as the devices they can reach. This is the reason why they are closed by default, since with this we avoid exposing all our devices to the rest of the Internet.
No need to use the DMZ almost never
The key here is that the opening of ports on devices such as consoles is usually done automatically thanks to uPnP. This is the reason why, probably, you have not had to open a port on your router for years to use some network service. It is different if you create a local server on your PC for your friends to access, as it may be necessary with games like Minecraft or Garry’s Mod.
Thus, using DMZ permanently is not a problem on consoles with a closed operating system , but it can be with other devices. Therefore, it is advisable to use it only when we have a specific problem when opening ports, since the router’s firewall is far from perfect, and we can have intrusion problems in our network .