General
The FritzBox modem/router can function as a simple VoIP PBX. It's important to know that in the FritzBox, you don't configure a VoIP trunk but a VoIP account. For each VoIP account, it's possible to receive calls for 1 number.
Known issues
During intensive internet use, call quality may deteriorate.
- Go to 'Internet' followed by 'Filters' in the FritzBox
- Click on the 'Prioritization' tab
- Add a rule under 'Prioritized Applications'
- Select 'All devices' and 'Internet telephony'
- Save the page
Configuration
To set up a VoIP account on the FritzBox, the following settings need to be configured.
Go to the Telephony tab and then click on Telephone numbers. Here you will see an overview of the active phone numbers.
- Click on New Telephone Number at the bottom right of the page.
- Select IP-base line and click on Next, if prompted.
- For Telephony provider, select: Other provider
- For Telephone Number for Registration, enter your full (E164) phone number, for example: +31501234567.
- For Internal Telephone number, enter the number without area code, so 1234567.
- Username: Account ID
- Password: The corresponding password
- Registrar and Proxyserver: sipproxy.voipgrid.nl
- Leave other fields empty
- Click on Additional Settings
- For DTMF transmission, select RTP or Inband
- Insert area code for outgoing calls should be turned off.
- Use telephone number for registration should be unchecked.
- Always register via an internet connection can be unchecked.
- Contact internet telephony provider via should be set to Only via IPv4.
- Transport protocol can remain set to Automatic.
- Click on Next
- The FritzBox will verify the configuration in the next screen. Click Next here as well.
It's also possible to set the recently configured number as the main number. If desired, this should be selected in the menu above under "Line settings" in the Outgoing Telephone Number section.
IPv6
Using IPv6 can cause issues with various internet providers. Only do this if you experience problems.
- Go to "Internet" followed by "Account Information"
- Click on the 'IPv6' tab
- Here you can disable IPv6.