Node device, shared information update processing program, shared information update method, and information sharing system

A non-transitory computer-readable storage medium that stores a computer-executable program for a node device in an information sharing system, including a plurality of node devices mutually connectable through a network, the plurality of node devices saving the shared information in common with the plurality of node devices, the node device transmits predetermined data to other node devices, the medium being installed in each node device, the program comprising:

• instructions for saving version information, in a first version information saving unit, indicative of a version of shared information saved by the node device;
• instructions for transmitting data and version information corresponding to the transmitted data to the other node devices;
• instructions for receiving the data and version information which are transmitted from one of the plurality of node devices;
• instructions for judging whether the version information saved in the first version information saying unit is older than the version information received by the data receiving unit;
• instructions for saving the version information received by the data receiving unit in a second version information saving unit, in response to judging that the version information saved in the first version information saving unit is older than the version information received by the data receiving unit;
• wherein the second version information saving unit contains a predetermined number;
• and wherein the predetermined number represents a number of times the first version judgment unit has determined the version information saved in the first version information saving unit is older than the version information received by the data receiving unit, wherein the version information received is transmitted by a different one of the plurality node devices;
• instructions for judging whether the number of version information saved in the second version information saving unit reaches the predetermined number, wherein the predetermined number is two or more, and
• instructions for updating the shared information saved in the first version information saving unit to a new version shared information, in response to the judging the number of version information saved in the second version information saving unit reaches the predetermined number.

A shared information update method performed by a node device in an information sharing system including a plurality of node devices, mutually connectable through a network, the plurality of node devices saving shared information in common with the plurality of node devices, the node device transmits predetermined data to the other node devices, the method comprising steps of:

• saving, in a first version information saving unit, version information indicative of a version of the shared information saved by the node device;
• transmitting data and version information corresponding to the transmitted data to the other node devices;
• receiving data and version information which are transmitted from one of the plurality of node devices;
• judging whether the version information saved in the first version information saving unit is older than the version information received by the data receiving unit;
• saving, in a second version information saving unit, the version information received by the data receiving unit, in response to judging that the version information saved in the first version information saving unit is older than the version information received by the data receiving unit;
• wherein the second version information saving unit contains a predetermined number;
• and wherein the predetermined number represents a number of times the first version judgment unit has determined the version information saved in the first version information saving unit is older than the version information received by the data receiving unit, wherein the version information received is transmitted by a different one of the plurality node devices;
• judging whether the number of version information saved in the second version information saving unit reaches a predetermined number, wherein the predetermined number is two or more, and
• updating the shared information saved in the first version information saving unit to a new version shared information, in response to judging the number of version information saved in the second version information saving unit reaches the predetermined number.

An information sharing system including a plurality of node devices, mutually connectable through a network, the plurality of node devices saving shared information which is used in common with the plurality of node devices, a node device transmits predetermined data to other node devices, the node device comprising:

• a first version information saving unit that saves version information indicative of a version of the shared information saved by the node device;
• a data transmission unit that transmits data and version information corresponding to the transmitted data to the other node devices;
• a data receiving unit that receives data and version information which are transmitted from one of the plurality of node devices;
• a first version judgment unit that judges whether the version information saved in the first version information saving unit is older than the version information received by the data receiving unit;
• a second version information saving unit that saves the version information received by the data receiving unit, in response to the first version judgment unit judging that the version information saved in the first version information is older than the version information received by the data receiving unit;
• wherein the second version information saving unit contains a predetermined number;
• and wherein the predetermined number represents a number of times the first version judgment unit has determined the version information saved in the first version information saving unit is older than the version information received by the data receiving unit, wherein the version information received is transmitted by a different one of the plurality node devices;
• a second version judgment unit that judges whether the number of version information saved in the second version information saving unit reaches the predetermined number, wherein the predetermined number is two or more, and
• a shared information update unit that updates the shared information saved in the first version information saving unit to a new version shared information, in response to the second version judgment unit judging the number of version information saved in the second version information saving unit reaches the predetermined number.