title: How Device receives Direct Methods in the IoT Hub?
body: <p>As per the documentation of the Direct Method in the IoT Hub, it is stated that the user invokes a direct method through a service-facing URI <strong>"{iot hub}/twins/{device id}/methods/"</strong> and the device receives it on the MQTT topic <strong>"$iothub/methods/POST/{method name}/"</strong>
  <br>I have some confusion regarding how this mapping works.
  <br>Is there any internal mapping in the IoT hub that redirects the request to the specific device?
  <br>
  How do other devices identify that the method is not meant for them because the topic on which the device is listening does not seem to be device specific and we need only a particular device to receive that method invocation?</p>