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FritzBox CallMonitor

FritzBox CallMonitor


If you don't have a phone with a display, then you are not able to see who is calling you before you pick up. If this phone is connected to a FRITZ!Box however, then this information can be accessed via a build in "CallMonitor" interface.


To use the CallMonitor you have to enable it on the FRITZ!Box first. Type this key sequence on a phone connected to the FRITZ!Box: #96*5* Afterwards you should hear a short audio signal as confirmation. If you want to disable it again then you have to type: #96*4* Again followed by a short audio signal as confirmation.

To test whether the port is actually open you can either test with the nmap program: nmap -p1012 where the output should look something like this: Nmap scan report for ( Host is up (0.00050s latency). PORT STATE SERVICE 1012/tcp open unknown Nmap done: 1 IP address (1 host up) scanned in 0.04 seconds Or you can test with the Telnet program: telnet 1012 If you see output like this: Trying Connected to Escape character is '^]'. then it successfully connected to the CallMonitor port. When you now make a call to or from a phone which is connected to the FRITZ!Box, then you can already see call information like this: date time;RING;connection_id;caller_number;callee_number;SIP1;\n date time;CONNECT;connection_id;extension_id;caller_number;\n date time;DISCONNECT;connection_id;duration_seconds;\n date time;CALL;connection_id;extension_id;caller_number;callee_number;SIP1;\n To disconnect the Telnet program press: CTRL ] and type: quit


When you start the program you will see a window like this:
FritzBoxCallMonitor MainWindow
and in the system tray you see this icon:
FritzBoxCallMonitor TrayIcon
In the window you can: When a call comes in then you will see a tray popup like this:
FritzBoxCallMonitor TrayPopup


The source code can be downloaded from