Patent ID: 11870893
Assignee: KABUSHIKI KAISHA TOSHIBA
Field: Computer technology (Electrical engineering)
Classification: CPC G  H | IPC G  H

Claim 0:
1. A secure computing method to be performed by a secure computing system comprising a secure computing management device and n computing devices, where n is an integer equal to or greater than two, communicatively coupled to the secure computing management device, the secure computing method comprising:
setting a coefficient selected from a ring of integers Q with X∈Q based on first data X input to the secure computing management device;
performing secret sharing on the first data X and generating n pieces of first fragment data, each associated with a corresponding one of the n computing devices, from the first data X based on the set coefficient;
causing, by each of the n computing devices, a learning model held in the computing device to learn the first fragment data associated with the computing device;
performing secret sharing on the second data Z and generating n pieces of second fragment data, each associated with a corresponding one of the n computing devices, from second data Z input to the secure computing management device based on the set coefficient;
performing, by each of the n computing devices, inference based on the second fragment data associated with the computing device using the learning model held in the computing device; and
obtaining decoded data dec by decoding k pieces of inference result data obtained as a result of inference performed by each of k computing devices among the n computing devices, where k is an integer equal to or greater than two and equal to or less than n, wherein
the coefficient is set to make each of the n pieces of first fragment data less than a maximum value of the ring of integers Q, wherein
the setting comprises setting, as the coefficient, a first coefficient r1, . . . , rk−1 and a second coefficient P1, . . . , Pn, the first coefficient r1, . . . , rk−1 corresponding to k−1 random elements of the ring of integers Q, the second coefficient P1, . . . , Pn corresponding to n random elements of the ring of integers Q, each associated with a corresponding one of the n computing devices,
the generating comprises generating n pieces of first fragment data W(P1), . . . , W(Pn) based on a polynomial of degree k−1

Σi=1k−1riPi+X 

with the first data X as an intercept, and
the first coefficient and the second coefficient are set to make a maximum value of the n pieces of first fragment data W(P1), . . . , W(Pn) less than the maximum value of the ring of integers Q.