Apparatus and method for giving the compressed encryption functionality to integer-based homomorphic encryption schemes

摘要

The present invention relates to a compressed encryption and decryption apparatus comprising: an interface receiving a public key, a secret key and a compression ratio; a memory storing instructions for encryption and decryption of plaintexts; and a processor encrypting and decrypting plaintexts according to the instruction, wherein the instruction comprises instructions performing; generating an extended public key and an extended secret key by revising the public key and the secret key according to the compression ratio; outputting the extended public key; receiving compressed ciphertext; and decrypting the compressed ciphertext using modulo operation for multiplication of the extended secret key and the compressed ciphertext.

主权项

1. An apparatus, comprising:
an interface receiving a public key, a secret key and a compression ratio; a memory storing instructions for encryption and decryption of plaintexts; and a processor encrypting and decrypting plaintexts according to the instructions, so as to provide compressed encryption and decryption functionality of integer-based homomorphic encryption by:
generating an extended public key and an extended secret key by revising the public key and the secret key according to the compression ratio;outputting the extended public key;receiving compressed ciphertext generated with the extended public key; anddecrypting the compressed ciphertext using modulo operation for multiplication of the extended secret key and the compressed ciphertext, wherein the compression ratio is a number of bits of the plaintext to be included in the compressed ciphertext.