Bidirectional communication system

A bi-directional communication system comprising:

• a first communication station and at least one second communication station, the second communication station receiving information delivery service from said first communication station through a first communication link, as well as performing data communication with said first communication station using a second communication link, in which
• said first communication station comprises a control transmitter transmitting through at least one of said first and second communication links, at least one of connection and disconnection control information to the second communication station, for controlling a connection/disconnection of the second communication station to the first communication station;
• and
• said second communication station comprises a connector/disconnector which uses said control information to control connection/disconnection of said second communication station to said first communication station through said second communication link, to control transmitting of a program of said information delivery service in real time, wherein:
• said first communication station which has said control transmitter comprises a problem detector detecting for occurrence of predetermined problems within the first communication station;
• and
• said control transmitter transmits said control information to said at least one second communication station according to content/nature of a problem detected by said problem detector.

A bi-directional communication system comprising:

• a first communication station and at least one second communication station, the second communication station receiving information delivery service from said first communication station through a first communication link, as well as performing data communication with said first communication station usiny a second communication link, in which
• said first communication station comprises a control transmitter transmitting throunh at least one of said first and second communication links, at least one of connection and disconnection control information to the second communication station, for controlling a connection/disconnection of the second communication station to the first communication station;
• and
• said second communication station comprises a connector/disconnector which uses said control information to control connection/disconnection of said second communication station to said first communication station through said second communication link, to control transmitting of a program of said information delivery service in real time, further comprising:
• an assignor assigning to a second communication station which requests an information delivery service through said second communication link, a protocol identifier useable in a station network;
• a storage for holding, after an information delivery service has been requested and the second communication link has been disconnected, said protocol identifier assigned to the second communication station until a delivery of said information delivery service from the first communication station to said second communication station has been completed.

A bi-directional communication system comprising:

• a first communication station and at least one second communication station, the second communication station receiving information delivery service from said first communication station through a first communication link, as well as performing data commulication with said first communication station using a second communication link, in which
• said first communication station comprises a control transmitter transmitting through at least one of said first and second communication links, at least one of connection and disconnection control information to the second communication station, for controlling a connection/disconnection of the second communication station to the first communication station;
• and
• said second communication station comprises a connector/disconnector which uses said control information to control connection/disconnection of said second communication station to said first communication station through said second communication link, to control transmitting of a program of said information delivery service in real time, wherein
• said second communication link is established by using point-to-point protocol as protocol of the data-link layer in the Open System Interconnection basic reference model.

A bi-directional communication system comprising:

• a first communication station and at least one second communication station, the second communication station receiving information delivery service from said first communication station through a first communication link, as well as performing data communication with said first communication station using a second communication link, in which
• said first communication station comprises a control transmitter transmitting through at least one of said first and second communication links, at least one of connection and disconnection control information to the second communication station, for controlling a connection/disconnection of the second communication station to the first communication station;
• and
• said second communication station comprises a connector/disconnector which uses said control information to control connection/disconnection of said second communication station to said first communication station through said second communication link, to control transmitting of a program of said information delivery service in real time,
• wherein on said second communication link, Internet Protocol is used as protocol of the network layer in the OSI basic reference model.

A bi-directional communication system comprising:

• a first communication station and at least one second communication station, the second communication station receiving information delivery service from said first communication station through a first communication link, as well as performing data communication with said first communication station using a second communication link, in which
• said first communication station comprises a control transmitter transmitting through at least one of said first and second communication links, at least one of connection and disconnection control information to the second communication station, for controlling a connection/disconnection of the second communication station to the first communication station;
• and
• said second communication station comprises a connector/disconnector which uses said control information to control connection/disconnection of said second communication station to said first communication station through said second communication link, to control transmitting of a program of said information delivery service in real time,
• wherein said second communication link is more specifically a plurality of communication links for data communication from said second communication station to said first communication station, and in which said second communication station comprises:
• a prioritizer assigning a predetermined priority to each communication link of said plurality of communication links;
• a selector selecting a communication link having a highest priority from communication links presently available among said plurality of communication links;
• and
• a connector which performs data communication using the selected communication link, and which, if another communication link with higher priority becomes available during data communication, switching connection from the selected communication link to the communication link with higher priority.

A bi-directional communication system comprising:

• a first communication station and at least one second communication station, the second communication station receiving information delivery service from said first communication station through a first communication link, as well as performing data communication with said first communication station using a second communication link, in which
• said first communication station comprises a control transmitter transmitting through at least one of said first and second communication links, at least one of connection and disconnection control information to the second communication station, for controlling a connection/disconnection of the second communication station to the first communication station;
• and
• said second communication station comprises a connector/disconnector which uses said control information to control connection/disconnection of said second communication station to said first communication station through said second communication link, to control transmitting of a program of said information delivery service in real time, wherein said connector/disconnector more specifically performs connecting and disconnecting of the second communication link in response to respectively the presence and absence of communication data from the second communication station.