Patent ID: 11962679
Assignee: DUALITY TECHNOLOGIES, INC.
Field: Digital communication (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. A method for collaborative multiparty homomorphic encryption, comprising:
receiving a linear common public key that is collaboratively generated by a plurality of parties each party of the plurality of parties contributing a linear public key share associated with the party, which in combination with linear public key shares associated with each of the other parties, generates the linear common public key that is a sum of the linear public key shares associated with the respective plurality of parties;
encrypting each of two ciphertexts with the linear common public key;
combining the two ciphertexts by a non-linear computation to generate a result ciphertext encrypted by a higher order non-linear public key;
re-encrypting the result ciphertext with a re-linearization key to swap encryption keys from the non-linear public key to a linear public key, wherein the re-linearization key represents encryptions of 2irs2 under the linear common public key associated with a linear common secret keys; and
distributing the re-encrypted result ciphertext to each of the plurality of parties to each partially decrypt the re-encrypted result ciphertext by a linear secret key share associated with the party, which in combination with partial decryptions of the re-encrypted result ciphertext by each of the other parties, fully decrypts the result by the linear common secret key that is a sum of the secret key shares of the respective plurality of parties.