Carefree and secure phone calls – with FRITZ!Box and FRITZ!Fon

While you sit back and relax on the phone, your FRITZ!Box automatically makes sure that everything is running smoothly and securely. In this guide article you will find out about what goes on in the background to ensure your phone calls are secure and which additional security features you can activate.

FRITZ!Fon uses secure DECT technology

Once registered with the FRITZ!Box, your FRITZ!Fon automatically uses an encrypted DECT radio connection to the FRITZ!Box – you don't have to do anything else and benefit immediately from the FRITZ!Box's high security standards. Of course, this also applies to most DECT phones from other manufacturers.

Do you use an IP phone via Wi-Fi? Not only then should you pay attention to secure Wi-Fi encryption. Discover tips and tricks in our guide article "How to keep your home Wi-Fi safe".

Modern telephony via VoIP

Today's Voice over IP (VoIP) has replaced older systems such as analog telephony or ISDN. Your FRITZ!Box ensures that phone calls are isolated from the rest of the internet traffic – meaning a DECT call is individually encrypted and protected within the home network.

The classic VoIP protocol SIP (Session Initiation Protocol) is often used unencrypted; Optionally, encryption can be activated for the connection between your FRITZ!Box and your provider. With FRITZ!OS 7.20 and later, this is possible on the part of the FRITZ!Box – your provider must also support encrypted telephony via VoIP.

Important and optional security features

For optimum security, it is recommended that the FRITZ!Box only allow secure DECT connections and activate the expanded security functions – these settings are enabled upon delivery under “Telephony> DECT”. 

The FRITZ!Box telephone system has additional security features that you can activate if you wish: You can disable the use of internet telephony from the home network. Telephony devices registered with the FRITZ!Box continue to work. Other SIP clients, on the other hand, are blocked to protect against malware. You can also limit the number of international calls. These settings can be found under "Telephony / Telephone Numbers / Interference Resistance". Under "Call handling", it is also possible to block international or premium rate numbers altogether.

If you want to get more information about your phones, you can use the DECT Monitor, which you can find under "Telephony > DECT > Monitor". Open this feature in the FRITZ!Box user interface and see everything you need to know about your cordless phone's connection to the FRITZ!Box. Pay attention to the values for the entries "Encryption" (information on the encryption of the current call) and "Extended Security" (indicates whether additional security procedures are supported).

Your FRITZ!Box automatically ensures secure phone calls. You can make changes to and use further settings as required to ensure optimum security.