An accelerated fully homomorphic encryption scheme over the integers

Based on the public key compressing technique and the Chinese Remainder Theorem, an efficient somewhat homomorphic encryption (SWHE) scheme is proposed, whose security can be reduced to the approximate greatest common divisor problem. Then the fully homomorphic encryption scheme is obtained by using Gentry's squashing decryption circuit technique, which could resist chosen plaintext attacks. The efficiency analysis shows that our SWHE scheme's public key size and ciphertext size are reduced compared to DGHV scheme. And the simulation results show that the multiplication of the proposed SWHE scheme is much more efficient than that of DGHV scheme.