Patent ID: 8073901
Filing Date: 2011-12-06
Classification: G06F

Abstract:
1. An information update method for updating information stored in a first storage unit and information stored in a second storage unit in an information update system comprising a first server having the first storage unit, a second server having the second storage unit, and a client device which requests update of information directed to the first server and the second server, and where the first server is coupled to the second server, wherein: the client device executes: a first update request sending operation in which an information update request having information which relates to update of the information and includes update information to be updated, is sent to the first server; and the first server executes: a first update request receiving operation for receiving the information update request sent from the client device; a first judgment operation in which it is judged whether a first access from the first server to the second server is possible; a second update request sending operation in which the information update request is sent to the second server when a result of the first judgment operation shows that the first access is possible; a second judgment operation in which the first server makes a judgment whether a second access is possible, when a result of the first judgment operation shows that the first access is not possible, and during a period after a predetermined time lapses since a judgment is made by the first judgment operation; a third update request operation in which the first server sends the information update request to the second server when the second judgment judges that the second access is possible; and a first update operation in which the update information included in the information update request is stored in the first storage unit based on the information update request; and the second server executes: a second update request receiving operation for receiving the information update request from the first server; an inconsistency judgment operation in which the second server judges whether an inconsistency exists between the update information included in the information update request and the information stored in the storage unit of the second server, when the information update request is received from the first server, an inconsistency notification operation in which the second server sends inconsistency information that indicates a content of inconsistency of the information update information stored in the second storage unit, and a server identifier that is information based on which the client device identifies the second server, to the client device, when it is judged that the inconsistency exists in the inconsistency judgment operation; an update information receiving operation for receiving the update information determined by the client device based on the inconsistency information that is sent from the second server in the inconsistency notification operation, the update information stored in the second storage unit, and the server identifier; and a second update operation in which the update information received from the client device in the update information receiving operation is stored in the second storage unit.