| 摘要 |
PROBLEM TO BE SOLVED: To provide a key generating device for achieving a practical homomorphic encryption scheme. SOLUTION: Of the key generating device, an arbitrary value generating section 116 generates n (n is a positive integer) arbitrary valuesλ<SB>i</SB>(i=0, ..., n-1) whose absolute value is equal to or larger than a prescribed value. By using these values, an encryption key generating section 117 generates, as an encryption key of a homomorphic encryption scheme, a matrix of n×n determined to a circulant matrix rot (v) of n×n when n elements corresponding to the result of discrete Fourier transform of the n arbitrary valuesλ<SB>i</SB>(i=0, ..., n-1) is set to be v<SB>i</SB>(i=0, ..., n-1). COPYRIGHT: (C)2011,JPO&INPIT |
