Data protection system, method, and program

The data dividing unit divides data into n pieces. An encoding unit generates m pieces of encoded data composed of a set of a bitmap matrix specifying a plurality pieces of divided data for obtaining exclusive OR (XOR) and exclusive OR data including exclusive OR of the plurality pieces of divided data specified by the bitmap matrix, wherein m is equal to or more than a dividing number n and according to redundancy. A distributed saving unit distributes and saves the m pieces of encoded data to and in storage devices at two or more locations and m or less locations. A decoding unit restores the original data by retrieving restorable k or more pieces of the encoded data among the distributed and saved m pieces of encoded data and subjecting the bitmap matrix of the retrieved encoded data to conversion into a unit matrix.