To the knowledge base
Knowledge document #3745

Setting up the FRITZ!Box for use with a fiber optic connection from

The FRITZ!Box Fiber is optimally prepared for use with Simply connect the FRITZ!Box to the fiber optic connection and select as the internet service provider in the FRITZ!Box.

The complete FRITZ!Box range of functions for internet and multimedia is then available to all of the devices in your home network without restriction.

Important:Currently, we do not have any information about how to use's telephony function with the FRITZ!Box. As soon as we find out, we will update this guide.

Requirements / Restrictions

  • A FRITZ!Box Fiber with the SFP module "FRITZ!SFP AON" is required for active fiber optic connections (AON).
  • A FRITZ!Box Fiber with the SFP module "FRITZ!SFP XGS-PON" is required for passive fiber optic connections (XGS-PON).

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

1 Unlocking your FRITZ!Box

Modem ID on the FRITZ!Box's type label
  1. Call's customer service at 088 0038500 to have them unlock the FRITZ!Box. For this, give them the "modem ID" on the FRITZ!Box's type label.

2 Inserting the SFP module into the FRITZ!Box

The FRITZ!Box is available in several different product variants, each of which is delivered with different components. If there was no SFP module inserted in your FRITZ!Box, perform the following steps:

  1. Insert the SFP module that is suitable for your fiber optic connection into the fiber slot of the FRITZ!Box:
    1. If you have an active fiber optic connection (AON), insert the SFP module "FRITZ!SFP AON" into the fiber slot of the FRITZ!Box.
    2. If you have a passive fiber optic connection (XGS-PON), insert the SFP module "FRITZ!SFP XGS-PON" into the fiber slot of the FRITZ!Box.
      Inserting the SFP module into the FRITZ!Box

      Important:If you do not know what kind of fiber optic connection you have, test both of the SFP modules supplied with the FRITZ!Box. The Power/Fiber LED on the FRITZ!Box remains lit as soon as the FRITZ!Box is connected to the fiber optic connection using the correct SFP module.

3 Connecting the FRITZ!Box to your fiber optic connection

  1. Remove the dust protection caps from the fiber optic cable, the SFP module in the FRITZ!Box, and from the fiber optic socket (OTO).
  2. Connect the fiber optic cable to the SFP module in the FRITZ!Box and to the fiber optic socket. Do not bend the fiber optic cable and do not hold the ends of the cable in front of your eyes.

    Note:You can find information on selecting a suitable fiber optic cable in our guide Which fiber optic cable do I need?

    Connecting the FRITZ!Box to the fiber optic connection

4 Plugging the FRITZ!Box in

  1. Plug the power adapter into the FRITZ!Box's power socket and plug it into a power outlet.

5 Configuring the internet connection in the FRITZ!Box

  1. Open the FRITZ!Box user interface.
  2. Enter the FRITZ!Box password given on the type label of the FRITZ!Box and click "Log In".
  3. If the wizard for internet access does not start automatically, click "Wizards" and then "Configure the Internet Connection".
    Calling up the FRITZ!Box wizard
  4. Select "" from the drop-down list and enable the correct connection type.
  5. Click "Next" and follow the wizard's instructions.
  6. Now the FRITZ!Box checks whether the internet connection can be established. Configuration is complete as soon as the message "The internet connection check was successful" is displayed.

    Important:If the internet connection check fails, your internet access may not have been activated yet. In this case, contact