Patent ID: 9208351
Filing Date: 2015-12-08
Classification: G06F,H04L

Abstract:
1. A method for processing information, said method comprising: an apparatus dividing target information into N pieces of divided data using a secret sharing scheme in which a predetermined number (K) of pieces of the N pieces of divided data is required to restore the target information, wherein N>K, and wherein the apparatus is an information processing device or an external storage device; said apparatus selecting M pieces from the N pieces, wherein K<M<N; after said selecting M pieces, storing the M pieces in the external storage device which limits a totality of pieces of the N pieces being stored on the external storage device to the M pieces; after said storing the M pieces, restoring the target information from at least K pieces of the N pieces; after said restoring, destroying D pieces of the M pieces in the external storage device, wherein D>M−K, determining a reference time; and after said storing the M pieces and before said destroying D pieces, said external storage device ascertaining that a predetermined operation has been performed with respect to the external storage device and that the reference time has elapsed since the predetermined operation was performed, wherein said destroying in response to said ascertaining.