Hello @GMAPRO,
welcome to this moderated Azure community forum.
The Azure IoT Hub supports MQTT as communication protocol. It does not support full MQTT broker abilities like the EventGrid Namespace MQTT broker but uses it for the Device twin features.
Check out this blog post where C# is used to connect via MQTT. or Python.
These are making use of the device SDK.
If you connect directly, use the 'public device endpoint'.
This is probably the hostname '[iot hub name].azure-devices.net'.
I have not used this way to communicate with the IoT Hub but connecting to the EventGrid Namespace MQTT broker works with the same kind of hostname as seen in this Nanoframework example.
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