Patent ID: 7647388
Filing Date: 2010-01-12
Classification: H04L

Abstract:
1. A control information transmission method for use in a communication system comprising a controlled device connected to the Internet via a router not publicizing an IP address thereof, and compatible with a protocol on a client side and a server side of HTTP; a terminal for transmitting control information via the Internet for controlling said controlled device; and an intermediary server, connected to the Internet, for receiving the control information transmitted from said terminal and transmitting the control information to said controlled device for carrying out communication between said controlled device and said terminal, said method comprising the steps of: transmitting, by said controlled device, a connection request signal to said intermediary server, with a TCP connection mode for communication with said intermediary server being set as an active connection mode; receiving, by said intermediary server, the transmitted connection request signal, with a TCP connection mode for communication with said controlled device being set as a passive connection mode, and authenticating said controlled device; changing, by said controlled device, the TCP connection mode of said controlled device to the passive connection mode and changing, by said intermediary server, the TCP connection mode of said intermediary server to the active connection mode after authenticating, by said intermediary server, said controlled device as a controlled device enabled for communication; making said controlled device wait as a server in an operation wait status under the HTTP protocol while maintaining a TCP connection in which the TCP connection mode of said controlled device has been changed to the passive connection mode and the TCP connection mode of said intermediary server has been changed to the active connection mode; and transmitting, by said intermediary server, when receiving the control information transmitted from said terminal via the Internet for controlling said controlled device, the control information to said controlled device waiting as the server.