The direct method works on a request-response interaction with the IoT device and backend solutions. The direct method has a timeout. If no reply is received within that expected time, the direct method will fail. These synchronous requests have, by default, 30 seconds of timeout; one can modify the timeout and increase it up to 3600 seconds, depending on the IoT scenarios you have. The device needs to connect using the MQTT protocol, whereas the backend solution can use HTTP.