| 摘要 |
PROBLEM TO BE SOLVED: To delete the update history of data at an early stage and to reduce the amount of update history of data in a data sharing system which holds the state of data to be equal to that of the other terminal. SOLUTION: The amount of data to be transmitted is less in the transmission of the copy 111 of inspection destination data and history application information 511 (90 bytes in total) compared to the transmission of update histories 212-215 (100 bytes in total) which are extracted by an extraction part 150 and are to be transmitted to the other terminal. Thus, a comparison part 200 judges that, the update histories 212-215 are those which are not necessary to be transmitted to the other terminal. A transmission part 300 transmits the copy 111 of inspection destination data and history application information 511 to the other terminal. A deletion part 400 judges that the update histories 212-215 are not required in all the terminals and deletes the update histories 212-215 from a terminal 21.
|
