Compression and indeterminate expansion of RLWE ciphertexts

摘要

Method 600 includes obtaining a plaintext query 134 comprising a series of plaintext integers 136 , and generating a polynomial 172 having coefficients 173 comprising the series of plaintext integers of the plaintext query. including the steps of The method also includes encrypting the polynomial using the secret encryption key 132 , and sending the encrypted polynomial 182 to the server 111 . The secret encryption key is randomly sampled from the ciphertext space, and the server encrypts the polynomial using the public encryption key 130 to obtain a set of encrypted integers 210 corresponding to the set of plaintext integers. is configured to expand. The method also includes receiving the encrypted result 192 from the server. The encrypted result is based on a series of encrypted integers.