Abstract: A method for monitoring, by a device manager (143) at a back-end server (140) a connection status of a device (100) accessible via a network (130) by a broker (144) using MQTT (Message Queuing Telemetry Transport) commands, the method comprising performing at the broker (144) the steps of: establishing (306) a handshake connection with the device (100); receiving (306A) from the device (100) an LWT (Last Will and Testament) message; notifying (308A) the device manager (144) about the device connection status as connected; periodically sending (310) to the device (100) at least one probe message; and if no response to the probe message is received from the device (100) (312, 313), sending (313A) the LWT message to the device manager (144) to notify the device manager (144) about the device connection status as disconnected.