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

The FRITZ!Box is optimally prepared for use with DELTA. Simply connect the FRITZ!Box to the fibre optic connection, select DELTA as the internet service provider in the FRITZ!Box, and configure telephony.
The complete FRITZ!Box range of functions for internet, telephony, and smart home is then available to all of the devices in your home network without restriction.
Requirements / Restrictions
- AON or GPON fibre optic connection. The FRITZ!Box cannot be used directly with XGS-PON fibre optic connections.
NoteOn an XGS-PON connection you can configure the FRITZ!Box for the internet connection via 'WAN' and use it behind the fibre optic modem from the internet service provider.
Note:All instructions on configuration and settings given in this guide refer to the latest FRITZ!OS for the FRITZ!Box.
1 Connecting the FRITZ!Box to your fibre optic connection
- Remove the dust protection caps from the fibre optic cable, the SFP module in the FRITZ!Box, and from the fibre optic socket.
- Connect the fibre optic cable to the SFP module in the FRITZ!Box and to the fibre optic socket. Do not bend the fibre optic cable and do not hold the ends of the cable in front of your eyes.
Note:Some fibre optic connections use a fibre terminating unit from Attema which requires a special fibre optic cable that is clamped into a carriage in the socket. Such cables are available from vendors. You can find information on selecting a suitable cable in our guide Which fibre optic cable do I need?

Connecting the FRITZ!Box to the fibre optic connection
2 Plugging the FRITZ!Box in
- Plug the power adapter into the FRITZ!Box's power socket and plug it into a power socket.
3 Unlocking your FRITZ!Box

- If you are using the FRITZ!Box with an XGS-PON fibre optic connection, call Delta's customer service at 0118 225525 to have them unlock the FRITZ!Box for your connection. For this, give them the 'modem ID' on the FRITZ!Box's type label. If you are asked for the MAC address of the FRITZ!Box, give them a fictitious MAC address, for example ab:00:00:00:00:00.
4 Configuring the internet connection in the FRITZ!Box
- Open the FRITZ!Box user interface.
- Enter the FRITZ!Box password given on the type label of the FRITZ!Box and click on 'Log In'.
- If the wizard for internet access does not start automatically, click on 'Wizards' and then on 'Configure the Internet Connection'.

Calling up the FRITZ!Box wizard - Select 'DELTA / Caiway' from the drop-down list.
- Click on 'Next' and follow the wizard's instructions.
- 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 DELTA.
5 Setting up telephony in the FRITZ!Box
Having your login information ready
- Have the login information for telephony ready (for example the username and password) that was displayed to you in MijnDELTA's customer portal.
Note:If your login information is not displayed in the customer portal, contact DELTA.
Setting up the telephony connection
- Click on 'Telephony' in the FRITZ!Box user interface.
- Click on 'Phone Numbers' in the 'Telephony' menu.
- Click on the 'Line Settings' tab.
- Click on 'Changing the Settings' in the 'Telephony connection' section.
- Click on 'Connection Settings for DSL/WAN'.
- Enable the option 'VLAN required for internet telephony'.
- Enter 102 in the field 'VLAN ID'.
- Enter 5 in the field 'PBit'.
- Enable the 'Use a separate connection (PVC) for Internet telephony' option.
- By 'Is account information required?', enable the option 'No'.
- Enable the option 'Obtain the IP address automatically (DHCP)'.
- Click on 'Apply' to save the settings.
Configuring phone numbers
- Click on 'Telephony' in the FRITZ!Box user interface.
- Click on 'Phone Numbers' in the 'Telephony' menu.
- Click on the 'New Phone Number' button.
- Select 'Other provider' from the drop-down list.
- Enter your phone number including the area code (for example 31201234567) by 'Telephone number for registration'.
- Enter your phone number (for example 1234567) by 'Internal phone number in the FRITZ!Box'.
- Enter the login information you received from DELTA by 'Username' and 'Password'.
- Enter voice.caiw.net in the field 'Registrar'.
- Enter voice.caiw.net in the 'Proxy server' field.
- Enter your area code by 'Area Code'.
- Click on 'Additional Settings' to display all of the settings.
- Select 'RTP or in-band' for 'DTMF transmission'.
- Click on 'Next' and follow the wizard's instructions.
Adjusting the number format
- Click on 'Telephony' in the FRITZ!Box user interface.
- Click on 'Phone Numbers' in the 'Telephony' menu.
- Click the
(Edit) button for the respective internet phone number. - Click on 'Telephone Number Format'.
- Select the option 'None' for the country code and area code in the 'Telephone Number Format' section.
- Click on 'Apply' to save the settings.
Assigning phone numbers
- Click on 'Telephony' in the FRITZ!Box user interface.
- Click on 'Telephony Devices' in the 'Telephony' menu.
- Click on the
(Edit) button for the respective telephony device. Important:If the telephony device was not configured yet, click on the 'Configure New Device' button and follow the wizard's instructions.
- From the 'Outgoing Calls' drop-down list, select the number to be used by the telephony device for making outgoing calls. If you do not select a phone number, the number entered under 'Telephony > Telephone Numbers > Line Settings' is used for making calls.
- Select the phone numbers to which the telephony device should react when you receive calls. You can select up to ten numbers (including the number for outgoing calls).
- Click on 'Apply' to save the settings.