Communication terminal device, information communication system, recording medium, and information communication method

A communication terminal device connected to a network and performing data communications with another communication terminal device through the network, comprising:

• circuitry configured to:
• monitor whether or not a new master unit other than a current master unit registering a self device exists in the other communication terminal device, while the self device is operating by a slave unit operation mode;
• acquire first judging criterion information used as a criterion for judging a priority as the master unit of the current master unit and second judging criterion information used as a criterion for judging a priority as the master unit of the new master unit;
• select when the circuitry judges that the new master unit exists, one of the current master unit or the new master unit as the master unit of the self device based on comparing the first judging criterion information and the second judging criterion information;
• wherein
• the slave unit operation mode is the operation mode of the communication terminal device operating as a slave unit.

An information communication system comprising a plurality of communication terminal devices connected to a network,

• the communication terminal device comprising:
• a storage configured to store proper information used as a criterion for switching an operation mode between a master unit operation mode and a slave unit operation mode;
• and
• circuitry configured to
• switch the master unit operation mode of a self device to the slave unit operation mode based on the proper information, while the self device is operating by the master unit operation mode, wherein
• the master unit operation mode is the operation mode of the communication terminal device operating as a master unit, and
• the slave unit operation mode is the operation mode of the communication terminal device operating as a slave unit, wherein
• the proper information includes judging criterion information used as the criterion which judges the priority as the master unit of the self device, and
• the circuitry is further configured to:
• monitor whether or not the other communication terminal device is another master unit, when the self device operates by the master unit operation mode,
• acquire the judging criterion information of the other communication terminal device detected as the other master unit, and
• switch, while the self device is operating by the master unit operation mode and when the other master unit is detected by monitoring, the master unit operation mode of the self device to the slave unit operation mode based on the judging criterion information of the self device and the judging criterion information of the other master unit.

A non-transitory computer-readable storage medium storing computer-readable instructions that, when executed by a computer including storage and circuitry, cause the computer to perform a method comprising:

• storing proper information used as a criterion for switching an operation mode between a master unit operation mode and a slave unit operation mode;
• switching the master unit operation mode of a self device to the slave unit operation mode based on the proper information, while the self device is operating by the master unit operation mode, wherein
• the master unit operation mode is the operation mode of the computer operating as a master unit,
• the slave unit operation mode is the operation mode of the computer operating as a slave unit,
• the computer is connected to a network and performs data communications between another communication terminal device through the network, and
• the proper information includes judging criterion information used as the criterion which judges the priority as the master unit of the self device, the method further comprising:
• monitoring whether or not the other communication terminal device is another master unit, when the self device operates by the master unit operation mode;
• acquiring the judging criterion information of the other communication terminal device detected as the other master unit;
• and
• switching, while the self device is operating by the master unit operation mode and when the other master unit is detected by monitoring, the master unit operation mode of the self device to the slave unit operation mode based on the judging criterion information of the self device and the judging criterion information of the other master unit.

A non-transitory computer-readable storage medium storing computer-readable instructions that, when executed by a computer including circuitry, cause the computer to perform a method comprising:

• monitoring whether or not a new master unit other than a current master unit registering a self device exists in another communication terminal device, while the self device is operating by a slave unit operation mode;
• acquiring first judging criterion information used as a criterion for judging a priority as the master unit of the previous master unit and second judging criterion information used as a criterion for judging a priority as the master unit of the new master unit;
• selecting when the circuitry judges that the new master unit exists, one of the current master unit and the new master unit as the master unit of the self device based on the first judging criterion information and the second judging criterion information;
• wherein
• the slave unit operation mode is the operation mode of the computer operating as a slave unit, and
• the computer is connected to a network and performs data communications with the other communication terminal device through the network.

An information communication method for performing data communications between a plurality of communication terminal devices including circuitry, and having a master unit operation mode operating as a master unit and a slave unit operation mode operating as a slave unit, comprising:

• storing, by the circuitry, proper information used as a criterion for switching an operation mode between the master unit operation mode and the slave unit operation mode in each of the plurality of communication terminal devices;
• and
• switching, by the circuitry, when the communication terminal device is operating by the master unit operation mode, the master unit operation mode of a self device to the slave unit operation mode based on the proper information, wherein
• the proper information includes judging criterion information used as the criterion which judges the priority as the master unit of the self device, the method further comprising:
• monitoring, by the circuitry, whether or not another communication terminal device is another master unit, when the self device operates by the master unit operation mode;
• acquiring, by the circuitry, the judging criterion information of the other communication terminal device detected as the other master unit;
• and
• switching, by the circuitry, while the self device is operating by the master unit operation mode and when the other master unit is detected by monitoring, the master unit operation mode of the self device to the slave unit operation mode based on the judging criterion information of the self device and the judging criterion information of the other master unit.