A Comparison of the Homomorphic Encryption Schemes FV and YASHE

Tancrède Lepoint; Michael Naehrig

Paper 2014/062

A Comparison of the Homomorphic Encryption Schemes FV and YASHE

Tancrède Lepoint and Michael Naehrig

Abstract

We conduct a theoretical and practical comparison of two Ring-LWE-based, scale-invariant, leveled homomorphic encryption schemes – Fan and Vercauteren’s adaptation of BGV and the YASHE scheme proposed by Bos, Lauter, Loftus and Naehrig. In particular, we explain how to choose parameters to ensure correctness and security against lattice attacks. Our parameter selection improves the approach of van de Pol and Smart to choose parameters for schemes based on the Ring-LWE problem by using the BKZ-2.0 simulation algorithm. We implemented both encryption schemes in C++, using the arithmetic library FLINT, and compared them in practice to assess their respective strengths and weaknesses. In particular, we performed a homomorphic evaluation of the lightweight block cipher SIMON. Combining block ciphers with homomorphic encryption allows to solve the gargantuan ciphertext expansion in cloud applications.

Metadata

Available format(s): PDF
Category: Public-key cryptography
Publication info: Published elsewhere. Major revision. AFRICACRYPT 2014
Keywords: Leveled Homomorphic Encryption Parameter Selection Implementations BKZ SIMON
Contact author(s): tancrede lepoint @ cryptoexperts com
History: 2014-03-13: revised; 2014-01-28: received; See all versions
Short URL: https://ia.cr/2014/062
License: CC BY

BibTeX

@misc{cryptoeprint:2014/062,
      author = {Tancrède Lepoint and Michael Naehrig},
      title = {A Comparison of the Homomorphic Encryption Schemes FV and YASHE},
      howpublished = {Cryptology ePrint Archive, Paper 2014/062},
      year = {2014},
      note = {\url{https://eprint.iacr.org/2014/062}},
      url = {https://eprint.iacr.org/2014/062}
}