Abstract: A flexible network building method for a remote-programmable monitoring and controlling system including an intelligent network device, a local area network router, and a dominant host in communication with the local area network router, including: sending a dominant host beacon containing router connection data for the local area network router through the dominant host; the intelligent network device receiving the dominant host beacon sent from the dominant host, and logining to the local area network router; the dominant host logining to the intelligent network device; sending a control command to the intelligent network device through the dominant host; receiving and executing the control command using the intelligent network device; and the intelligent network device responding to the dominant host with an executing status message after the execution of the control command.