An example system includes a processor to receive a preprocessed query from a client device for a fully homomorphic encryption (FHE) encrypted database. The processor can execute the preprocessed query on the FHE encrypted database to generate a response. The processor can transmit a partially-processed response to the client device, which can post-process the query computation.

Provided is homomorphic encryption data processing method and apparatus and relates to homomorphic encryption data processing method and apparatus that set weighted values to a segment classification value (a logit value) and a distribution value of a dataset including a homomorphic encryption and uses weighted values to perform computation and learning of data in a state in which the homomorphic encryption is maintained.

A method for implementing a secure multiparty inner product computation between two parties using an SPDZ protocol involves having a first party and a second party compute, for i=1, . . . , k, a vector (I)=(II) based on a vector (x={x.sub.1, . . . , x.sub.N}), and a vector (w={W.sub.1, W.sub.N}), respectively, where (I)=(X.sub.2i-1X.sub.2i) (III)=W.sub.2i-1W.sub.2i, N is the total number of elements in the vectors k=N/2. The vectors (I), and (III) are securely shared between the parties. The parties then jointly compute SPDZ protocol Add([w.sub.2i], [x.sub.2i-1]) and Add([w.sub.2i], [x.sub.2i-1]) to determine shares [w.sub.2i-1+x.sub.2i] and [w.sub.2i+x.sub.2i-1] respectively, and then compute, for i=1, . . . , k, inner product shares [d.sub.i] by performing SPDZ protocol Mult([w.sub.2i-1+x.sub.2i], [w.sub.2i+x.sub.2i-1]). SPDZ protocol ([Add d.sub.1], . . . , [d.sub.k], -(IV), . . . , -(V), -(VI), -, (VII)) is then performed to determine the inner product.

Improved pseudonym certificate management is provided for connected vehicle authentication and other applications. Temporary revocation of a certificate is enabled. With respect to Security Credential Management Systems (SCMS), pre-linkage values can be employed. The pre-linkage values can be encrypted using homomorphic encryption. Other embodiments are also provided.

The method of constructing QAP-based Homomorphic Encryption (HE) in the semi-public setting is introduced, which comprises: encryption, computation, and decryption. The data receiver produces a semi-public key Key.sub.s-pub.The data provider can encode his k-qubit plaintext |x to a k-qubit ciphertext |ψ.sub.en=Q.sub.P|x via a k-qubit invertible operator Q.sub.P randomly generated by Key.sub.s-pub. From the provider, the message En(ζ.sub.p) of Q.sub.P encoded by a cryptosystem G.sub.crypt in Key.sub.s-pub is transmitted to the receiver through a small-resource communication channel and the ciphertext |ψ.sub.en is conveyed to the cloud. The receiver creates the instruction of encoded computation U.sub.en=PMQ.sub.P and transports to the cloud, where M is the required k-qubit arithmetic operation, P a k-qubit permutation, and a k-qubit operator to mingle with M. According the instruction, the cloud performs the encrypted evaluation U.sub.en|ψ.sub.en and transfer to the receiver. The decryption Key.sub.privU.sub.en|ψ.sub.en is conducted by the receiver via the private key Key.sub.priv=<

A public-key scheme of Homomorphic Encryption (HE) in the framework Quotient Algebra Partition (QAP) comprises: encryption, computation and decryption. With the data receiver choosing a partition or a QAP, [n, k, C], a public key Key.sub.pub=(VQ.sub.en, ) and a private key Key.sub.priv=.sup.†P.sup.\ are produced, where VQ.sub.en is the product of an n-qubit permutation V and an n-qubit encoding operator Q.sub.en, an error generator randomly provides a dressed operator Ē=V.sup.†EV of spinor error E of [n, k, C]. Then, by Key.sub.pub, the sender can encode his k-qubit plaintext |x into an n-qubit ciphertext |ψ.sub.en, which is transmitted to the cloud. The receiver prepares the instruction of encoded computation U.sub.en=PV.sup.†Q.sub.en.sup.† for a given k-qubit action M and sends to cloud, where is the error-correction operator of [n, k, C], =I.sub.2.sub.n−k.Math.M the tensor product of the (n−k)-qubit identity I.sub.2.sub.n−k and M, and V.sup.†Q.sub.en.sup.† and PSYSTEMS AND METHODS FOR MIXED PRECISION MACHINE LEARNING WITH FULLY HOMOMORPHIC ENCRYPTION