公开(公告)号：EP4228197A1

公开(公告)日：2023-08-16

申请号：EP23151712.9

申请日：2023-01-16

申请人： Seoul National University R & DB Foundation ,  Industry-Academic Cooperation Foundation, Chosun University

发明人： NO, Jong Seon ,  LEE, Joon Woo ,  KIM, Young Sik

IPC分类号： H04L9/00 ,  H04L9/08

摘要： A homomorphic encryption operation key management system receives a public key and a hierarchical Galois key from a client device, verifies validity of a token in response to receiving the token and a request for a homomorphic encryption operation key for the client device from a server, and generates the homomorphic encryption operation key using the public key and the hierarchical Galois key and transmits the homomorphic encryption operation key to the server when the token is valid.

公开(公告)号：EP4412143A1

公开(公告)日：2024-08-07

申请号：EP24154576.3

申请日：2024-01-30

申请人： Seoul National University R & DB Foundation ,  Industry Academic Cooperation Foundation Chosun University

发明人： NO, Jong Seon ,  LEE, Joon Woo ,  KIM, Young Sik

IPC分类号： H04L9/00

CPC分类号： H04L9/008

摘要： A server for performing an operation on a homomorphic ciphertext according to an embodiment of the present disclosure may be configured to: receive a first homomorphic ciphertext, a public key, and a first hierarchical Galois key set from a client device; in response to a request for generating a second hierarchical Galois key set for performing a rotation operation on the first homomorphic ciphertext of the client device, generate the second hierarchical Galois key set, based on the received public key and hierarchical Galois key set; and when a decomposition operation for a first Galois key included in the second hierarchical Galois key set overlaps with a decomposition operation for a second Galois key, first perform the decomposition operation for the first Galois key, and then substitute the decomposition operation for the second Galois key with a result of the decomposition operation for the first Galois key. In addition, the second hierarchical Galois key set may be sequentially generated according to a predetermined generation order.

公开(公告)号：EP4228198A1

公开(公告)日：2023-08-16

申请号：EP23151723.6

申请日：2023-01-16

申请人： Seoul National University R & DB Foundation ,  Industry-Academic Cooperation Foundation, Chosun University

发明人： NO, Jong Seon ,  LEE, Joon Woo ,  KIM, Young Sik

IPC分类号： H04L9/00

摘要： In a client-server model for generating a rotation operation key in fully homomorphic encryption, a client transmits a public key and a hierarchical Galois key generated using a secret key to a server, and the server performs a rotation operation on the public key using the hierarchical Galois key to directly generate one or more rotation operation keys, so that the server may generate a rotation operation key if necessary while computational burden and communication cost of the client are reduced.

公开(公告)号：EP3896895A1

公开(公告)日：2021-10-20

申请号：EP21163199.9

申请日：2021-03-17

申请人： Samsung Electronics Co., Ltd. ,  SNU R&DB Foundation ,  Industry Academic Cooperation Foundation Chosun University

发明人： NO, Jong Seon ,  LEE, Yong Woo ,  KIM, Young Sik ,  LEE, Joon Woo

IPC分类号： H04L9/00 ,  H04L9/30

摘要： A method and apparatus for processing a ciphertext based on homomorphic encryption. The method includes determining an approximate polynomial corresponding to a modulus reduction for bootstrapping a ciphertext based on samples extracted from the modulus reduction, and bootstrapping the ciphertext based on the approximate polynomial.

公开(公告)号：EP3902195A1

公开(公告)日：2021-10-27

申请号：EP21169784.2

申请日：2021-04-22

申请人： Samsung Electronics Co., Ltd. ,  SNU R&DB Foundation ,  Industry Academic Cooperation Foundation Chosun University

发明人： NO, Jong Seon ,  LEE, Yong Woo ,  LEE, Eunsang ,  LEE, Joon Woo ,  KIM, Young Sik

IPC分类号： H04L9/00

摘要： An encryption method and apparatus based on homomorphic encryption using a composition of functions. The encryption method includes generating a ciphertext by encrypting data, and bootstrapping the ciphertext by performing a modular reduction based on a composition of a function for a modulus corresponding to the ciphertext.