| 摘要 |
In a cable system, a video data of a cable program is distributed from a center system to a subscriber terminal device via a cable network by using one of frequency-divided channels of broadcast programs, and two-way communication is carried out between the subscriber terminal device and the center system via the cable network. A management unit, provided in the center system, determines whether a request for two-way communication sent by the subscriber terminal device is received when the video data is distributed to the subscriber terminal device by using a corresponding one of the frequency-divided channels of broadcast programs. A multiplexing unit, provided in the center system, multiplexes the video data and two-way communication downstream data into a multiplex signal of the corresponding broadcast channel when the reception of the request is determined by the management unit, so that the center system transmits the multiplex signal to the subscriber terminal device via the cable network by using the corresponding broadcast channel. A data isolation unit, provided in the subscriber terminal device, isolates the downstream data and the video data from the multiplex signal of the corresponding broadcast channel, which is received at the subscriber terminal device. <IMAGE> |
