Patent ID: 7657739
Filing Date: 2010-02-02
Classification: G06F

Abstract:
1. A judgment device that judges whether an object is invalid using a blacklist, the judgment device comprising: a holding unit operable to hold the blacklist indicating whether the object is invalid, and operable to hold a whitelist indicating whether the judgment device is valid; a judgment unit operable to judge whether the whitelist needs to be updated; an acquisition unit operable to, when the judgment unit judges that the whitelist needs to be updated, acquire together a latest blacklist and a latest whitelist, the acquisition unit acquiring the latest blacklist and the latest whitelist regardless of whether a judgment is made as to whether the blacklist needs to be updated; and an update unit operable to (i), when the judgment unit judges that the whitelist needs to be updated, write together the acquired latest blacklist and the acquired latest whitelist, respectively over the blacklist and the whitelist in the holding unit, and (ii), when the judgment unit judges that the whitelist does not need to be updated, perform no update of the blacklist and the whitelist held in the holding unit.