Patent ID: 9680639
Date: 2017-06-13
CPC Classifications: H04L

Claim:
1. A secret sharing apparatus which generates a plurality of shared data from secret data, wherein: the secret data is restored from at least two of the plurality of shared data, the secret data is divided into a plurality of pieces of divided data and does not include a random number, the plurality of pieces of divided data are grouped into a plurality of divided groups each of which has a plurality of columns, each including a piece of the divided data, the secret sharing apparatus comprises: a shared data generator which performs an XOR operation between pieces of the divided data located in corresponding columns of each divided group and generates the plurality of shared data including a first shared data and a second shared data, a piece of each of the shared data includes a result of the XOR operation, and a transmitter which transmits at least the first shared data to a first apparatus and the second shared data to a second apparatus, wherein a first divided group, which is one of at least two divided groups generating the first shared data, is shifted at least one column relative to column positions of the first divided group when used as one of at least two divided groups generating the second shared data.