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Setting up a DMZ with the FRITZ!Box

A DMZ (demilitarized zone) is a special network that can be accessed from the internet and the local network (LAN). A firewall completely blocks access from the DMZ to the LAN. This concept allows you to make server services (such as email servers) in the DMZ available for access from the internet and from the LAN, but does not make you vulnerable to attacks on the LAN from the internet.

Note:All instructions on configuration and settings given in this guide refer to the latest FRITZ!OS for the FRITZ!Box.

1 The FRITZ!Box does not support DMZ

FRITZ!Box does not support the implementation of a DMZ (demilitarized zone).


The term "DMZ" is often incorrectly used for the "exposed host" function. If you use the "exposed host" function, all of the ports are opened for a device in the network.

The following step is only necessary if you want to set up an "exposed host" for a device in the FRITZ!Box home network instead of a "DMZ":

Important:Incoming connections to destination ports for which you configured separate port sharing rules are not forwarded to the "exposed host". Instead, they are forwarded to the device specified in the separate port sharing rule.

  1. Click "Internet" in the FRITZ!Box user interface.
  2. Click "Permit Access" in the "Internet" menu.
  3. Click on the "Port Sharing" tab.
  4. Click the (Edit) button for the (computer) name of the device that you want to set up an exposed host for. If you have not configured any sharings for the device yet:
    1. Click "Add Device for Sharing".
    2. Select the (computer) name of the device from the drop-down list "Device".

      Note:If you cannot select the device, you can select "Enter the IP address manually" and enter the IP address. Only devices that automatically obtain their IP settings (DHCP) from the FRITZ!Box are listed in the drop-down list.

  5. Enable the option "Open this device completely for internet sharing via IPv4 (exposed host)".
  6. If the device supports the IPv6 protocol and you also want to set up the exposed host for IPv6 internet access, enable the option "Open this device completely for internet sharing via IPv6 (exposed host)".

    Note:This option is only displayed if IPv6 support is enabled in the FRITZ!Box under "Internet > Account Information > IPv6".

  7. Click "OK" to save the settings.