The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 25, 2011
Filed:
Feb. 04, 2008
Shoji Kodama, Sagamihara, JP;
Kiyotake Kumazawa, Tokyo, JP;
Shoji Kodama, Sagamihara, JP;
Kiyotake Kumazawa, Tokyo, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A problem of prior art is that normal backup data is lost as a result of taking a backup by overwriting the normal backup data with data that has been changed greatly from a virus infection or the like. This invention provides a computer system having a storage system. The storage system contains a first storage area and a second storage area for storing a copy of data that is stored in the first storage area at one point in time. Only when the differential amount indicating the difference between data stored in the first storage area and data stored in the second storage area is smaller than a predetermined threshold, the storage system deletes the data which is stored in the second storage area and newly stores a copy of the data stored in the first storage area in the second storage area.