Patent ID: 7080399

Claim:
A network control system for transmitting data between devices by using a plurality of data transmission modes in a network in which at least two devices for handling at least one kind of data among video data, audio data, and information data are connected through one transmission line, wherein: each of said at least two devices includes either or both of at least one target operable to receive a message and perform processing according to the message, and at least one controller operable to transmit the message and establish a connection for data transmission with said target; said network control system comprises said controller and said target; said controller and said target are each connected to one transmission line; said plurality of data transmission modes comprise a first data transmission mode which comprises a message transmission for transmitting the message and a message response which is a response to the message transmission, and a second data transmission mode for data transmission on an established connection; said controller is operable to establish, before data transmission, a connection of said second data transmission mode to said target; when said controller receives data of the message from said target, said controller is operable to make a data request by using said first data transmission mode; said target is operable to transmit the data onto the established connection by using said second data transmission mode according to the data request; and said controller is operable to receive the data by using said second data transmission mode.