We propose a protocol for converting the encryption function of a ciphertext into another encryption function while keeping the corresponding message secret. The proposed protocol allows conversions of the El Gamal and Paillier cryptosystems and has the potential to design an efficient multiparty protocol intended for circuits consisting of arithmetic and logical operations. We clarify the condition of circuits such that the multiparty protocol based on the proposed protocol provides better performance than previous approaches. In addition, we introduce some privacy-preserving statistical computations as an effective application of the proposed protocol.
|Number of pages||10|
|Journal||IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences|
|Publication status||Published - 1 Jan 2009|
- Encryption conversion
- Homomorphic encryption
- Multiparty protocol
- Privacy-preserving statistical computation