Method and system for data collection using public network and broadcasting

A system for collecting data from many terminals to a center having a plurality of center service ports through a public network, the system comprising:

• means for transmitting terminal data from the terminals to the center through the public network by carrying out a calling operation to call up the center at each terminal;
• means for collecting the terminal data received at the center service ports;
• means for measuring a congestion state of the center service ports;
• means for generating a control data for controlling the calling operation at each terminal such that the congestion state measured by the measuring means is improved, the control data indicating a call probability by which the calling operation at each terminal is carried out probabilistically;
• means for broadcasting the control data generated by the generating means from the center to the terminals;
• and
• means for controlling the calling operation at each terminal according to the control data broadcast by the broadcasting means, by determining whether or not to carry out the calling operation at each terminal by generating a random number, and comparing the random number with the call probability indicated by the control data.

A terminal device in a system for collecting data from many terminals to a center having a plurality of center service ports through a public network, the terminal device comprising:

• control data receiving means for receiving a control data for controlling a calling operation to call up the center at the terminal device broadcast from the center, the control data indicating a call probability by which the calling operation at the terminal device is carried out probabilistically;
• calling operation control means for determining whether or not to carry out the calling operation according to the control data received by the control data receiving means, by generating a random number and comparing the random number with the call probability indicated by the control data;
• data transmission means for transmitting terminal data through the public network to one of the center service ports by carrying out the calling operation when the calling operation control means determines to carry out the calling operation;
• and
• busy line handling means for restarting a probabilistic execution of the calling operation by restarting a reception of the call probability at the control data receiving means when a call made by the calling operation resulted in a busy state.

A terminal device in a system for collecting data from many terminals to a center having a plurality of center service ports through a public network, the terminal device comprising:

• control data receiving means for receiving a control data for controlling a calling operation to call up the center at the terminal device broadcast from the center, the control data indicating a call probability by which the calling operation at the terminal device is carried out probabilistically;
• calling operation control means for determining whether or not to carry out the calling operation according to the call probability received by the control data receiving means, by generating a random number and comparing the random number with the call probability indicated by the control data;
• data transmission means for transmitting terminal data through the public network to one of the center service ports by carrying out the calling operation when the calling operation control means determines to carry out the calling operation;
• and
• busy line handling means for restarting a probabilistic execution of the calling operation by restarting a reception of the call probability at the control data receiving means, while requesting the public network to count a number of lost calls overflowing at the center service ports, when a call made by the calling operation resulted in a busy state.

A center device in a system for collecting data from many terminals to a center having a plurality of center service ports through a public network, the center device comprising:

• data reception means for receiving terminal data from the terminals in response to arrivals of calls from the terminals to the center service ports;
• data collection means for collecting the terminal data received by the data reception means;
• congestion state measurement means for measuring a congestion state of the center service ports;
• control data generation means for generating a control data for controlling a calling operation at each terminal such that the congestion state measured by the congestion state measurement means is improved, the control data indicating a call probability by which the calling operation at each terminal is carried out probabilistically;
• and
• control data broadcast means for broadcasting the control data generated by the control data generation means to the terminals, such that whether or not to carry out the calling operation is determined at each terminal by generating a random number and comparing the random number with the call probability indicated by the control data.

A center device in a system for collecting data from many terminals to a center having a plurality of center service ports through a public network, the center device comprising:

• data reception means for receiving terminal data from the terminals in response to arrivals of calls from the terminals to the center service ports;
• data collection means for collecting the terminal data received by the data reception means;
• congestion state measurement means for measuring a congestion state of the center service ports, and obtaining a number of lost calls overflowing from the center service ports from the public network;
• control data generation means for generating a control data for controlling a calling operation at each terminal such that the congestion state measured by the congestion state measurement means is improved while the number of lost calls obtained by the congestion state measurement means is reduced, the control data indicating a call probability by which the calling operation at each terminal is carried out probabilistically;
• and
• control data broadcast means for broadcasting the control data generated by the control data generation means to the terminals, such that whether or not to carry out the calling operation is determined at each terminal by generating a random number and comparing the random number with the call probability indicated by the control data.