Patent ID: 11870889
Assignee: INDUSTRY ACADEMIC COOPERATION FOUNDATION CHOSUN UNIVERSITY
Field: Digital communication (Electrical engineering)
Classification: CPC H  G | IPC G  H

Claim 8:
9. An apparatus with homomorphic encryption, the apparatus comprising:
a receiver configured to receive a first ciphertext corresponding to a first modulus; and
a processor configured to
generate a second ciphertext corresponding to a second modulus by performing modulus raising on the first ciphertext, and
perform bootstrapping by encoding the second ciphertext using a commutative property and an associative property of operations included in a rotation operation,
wherein, for the performing of the bootstrapping, the processor is configured to:
perform a permutation operation on the second ciphertext; and
perform the bootstrapping by performing a key switching operation based on a result of the permutation operation, and
wherein, for the performing of the bootstrapping by performing the key switching operation based on the result of the permutation operation, the processor is configured to:
perform a rescaling operation based on the permutation operation;
perform a decompose operation on a result of the rescaling operation; and
perform a sum of multiplications on a result of the decompose operation.