Patent ID: 8266100

Claim:
An information processing apparatus comprising: a plurality of storage units including a first storage unit, a second storage unit, and a third storage unit; a writing unit configured to write same data in said plurality of storage units, wherein the writing unit writes a first part of the data in a first part of the first storage unit at a first timing, writes a second part of the data in a second part of the first storage unit and the first part of the data in a first part of the second storage unit at a second timing which is later than the first timing, writes the second part of the data in a second part of the second storage unit and the first part of the data in a first part of the third storage unit at a third timing which is later than the second timing, and writes the second part of the data in a second part of the third storage unit at a fourth timing which is later than the third timing; a reading unit configured to read a plurality of data written in said plurality of storage units; and an estimation unit configured to estimate normal data based on the plurality of data read by said reading unit when data of at least one combination out of the plurality of data read by said reading unit are determined not to match each other.