Edit Telephone Number

Telephony / Telephone Numbers / Edit Internet Telephone Number

On the "Edit Telephone Number" page you can edit the account information and settings for an internet telephone number.

Edit Telephone Number

The FRITZ!Box requires various data and settings for each internet telephone number:

  • internet telephone number and account data, in order to register the telephone number with the telephony provider,
  • number format, so that the telephone number is transmitted for outgoing calls as stipulated by the telephony provider.
  • additional settings in order to fulfill the specifications from the telephony provider.

Internet Telephone Number and Account Information

For preconfigured telephony providers, the standard information and standard settings are already entered in the FRITZ!Box and no longer displayed.

Setting / Entry FieldUse
Use Internet telephone number This setting must be enabled for you to be able to make outgoing and incoming telephone calls using the internet telephone number.
Display Name You can choose any name (for instance, "personal" or "office") to appear on the display of your handset whenever a call for this telephone number arrives. The display function can work only if it is supported by your telephone.
Registrar Name of your telephony provider's registrar. To ensure that you can be reached, the FRITZ!Box has to register your telephone number with the registrar (or SIP registrar).
Proxy server Enter the name of the proxy server, only if your telephony provider expressly requires that you enter a proxy server.
STUN server If the "STUN server" field is available, enter the name of your telephony provider's STUN server. The field is available for SIP trunking and when the FRITZ!Box uses a different router to connect to the internet.

Additional Settings for the Telephone Number

For preconfigured telephony providers, the standard information and standard settings are already entered in the FRITZ!Box and no longer displayed.

Setting / Entry FieldUse
DTMF transmission The default setting "automatic" is usually correct. If problems with telephone calls arise, consult your telephony provider about testing a different option.
Suppress Outgoing Caller ID (CLIR)

Specify which information the FRITZ!Box sends your telephony provider when you suppress your caller ID by enabling the CLIR option in the FRITZ!Box. The default setting "CLIR via display name" is usually correct. If problems with suppressing the caller ID arise, consult your telephony provider about testing a different option.

Do not enable the suppress outgoing caller ID (CLIR) option itself here. Use the telephone settings under "Telephony / Telephony Devices" instead.

Caller ID

Specify which telephone number is transmitted during outgoing calls. If this setting is disabled, the number saved in your account information from the telephony provider will be transmitted.

You can also transmit a different telephone number if your telephony provider supports this feature: Enter the desired number in the "Internet telephone number" field and ask your telephony provider which option must be selected for "Caller ID" (usually "Relay local telephone number in international telephone number format").

Provider supports G.726 in accordance with RFC 3551

Enable this option if your telephony provider supports the voice codec G.726 in accordance with RFC 3551.

Provider supports call-back on busy (CCBS) in accordance with RFC 4235

Enable this option if your telephony provider supports the call-back on busy (CCBS) feature in accordance with RFC 4235.

Additional Settings for the Connection

For preconfigured telephony providers, the standard information and standard settings are already entered in the FRITZ!Box and no longer displayed.

Setting / Entry FieldUse
Use telephone number for registration This setting is often called "SIP URI". Whether it has to be enabled or disabled depends on the telephony provider. If you have problems connecting, try out both settings, or contact your provider.
Always register via an Internet connection

Enable this setting if the provider of the internet telephone number is different from the provider of the internet connection.

If this setting is disabled, some Internet providers always establish a second internet connection for internet telephony. However, over this connection you can only make calls using the internet telephone numbers supplied by your internet provider.

Enable encrypted telephony If this setting is enabled and the telephony provider supports encrypted telephone calls via TLS/SRTP (for instance, Deutsche Telekom, Easybell, dus.net), then voice data will be encrypted during communication between the FRITZ!Box and the telephony provider.
The provider supports encrypted telephony via SRTP in accordance with RFC 3711 and RFC 4568
Provider does not support REGISTER-fetch Whether this setting has to be enabled or disabled depends on the telephony provider. If you have problems connecting, try out both settings, or contact your provider.