We present a multi-party computation protocol in the case of dishonest majority which has very low round complexity. Our protocol sits philosophically between Gentry’s Fully Homomorphic Encryption based protocol and the SPDZ-BMR protocol of Lindell et al. (CRYPTO 2015). Our protocol avoids various inefficiencies of the previous two protocols. Compared to Gentry’s protocol we only require Somewhat Homomorphic Encryption (SHE). Whilst in comparison to the SPDZ-BMR protocol we require only a quadratic complexity in the number of players (as opposed to cubic), we have fewer rounds, and we require less proofs of correctness of ciphertexts. Additionally, we present a variant of our protocol which trades the depth of the garbling circuit (computed using SHE) for some more multiplications in the offline and online phases.
|Title of host publication||Theory of Cryptography - 14th International Conference, TCC 2016-B, Proceedings|
|Editors||Adam Smith, Martin Hirt|
|Number of pages||28|
|State||Published - 2016|
|Event||14th International Conference on Theory of Cryptography, TCC 2016-B - Beijing, China|
Duration: 31 Oct 2016 → 3 Nov 2016
|Name||Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)|
|Conference||14th International Conference on Theory of Cryptography, TCC 2016-B|
|Period||31/10/16 → 3/11/16|
Bibliographical notePublisher Copyright:
© International Association for Cryptologic Research 2016.