The call monitor is a custom endpoint, which can be enabled in the FRITZ!Box using specific phone codes.
When the endpoint is enabled, a raw TCP stream is opened on port 1012 of the FRITZ!Box, which sends information about incoming and outgoing calls in real-time.
This can be used to integrate the FRITZ!Box call signaling into other applications or systems.
To enable the call monitor, you need to dial the following code on a connected telephone: #96*5*.
To disable the call monitor, dial: #96*4*.
Published under MIT License (see choose a license).