Multi-bit homomorphic encryption based on learning with errors over rings
Basing on Learning with errors over rings (RLWE) assumption, we provide a new multi-bit somewhat homomorphic encryption scheme. We introduce canonical embedding to transform a ring element into a vector, such that polynomial multiplication can be performed in  ~ (nlog n) scalar operations, and ciphertext size is reduced at the same time. The CPA security of this scheme can be reduced into RLWE assumption.