A Provably Secure and Efficient Verifiable Shuffle based on a Variant of the Paillier Cryptosystem

Lan Nguyen (University of Wollongong, Australia)

Reihaneh Safavi-Naini (Centre for Computer Security Research, University of Wollongong, Australia)

Kaoru Kurosawa (Ibaraki University, Japan)

Abstract: We propose a variant of the Paillier cryptosystem that improves efficiency in encryption, re-encryption and decryption while preserving the homomorphic property. We then use this variant to construct a new verifiable shuffle system and prove its security. We show that the new shuffle scheme has the least number of rounds and exponentiations compared to all known shuffle schemes. Finally, we show how to construct a publicly verifiable mix-net using the shuffle system.

Keywords: Paillier's public-key system, mix-nets, privacy, verifiable shuffles

Categories: E.3