Homomorphic sign evaluation with a RNS representation of integers

Philippe Chartier; Michel Koskas; Mohammed Lemou; Florian Méhats

Paper 2024/156

Homomorphic sign evaluation with a RNS representation of integers

Philippe Chartier, Ravel Technologies

Michel Koskas, Ravel Technologies

Mohammed Lemou, Ravel Technologies

Florian Méhats, Ravel Technologies

Abstract

In the context of fully-homomorphic-encryption, we consider the representation of large integers by their decomposition over a product of rings (through the Chinese Remainder Theorem) and introduce a new algorithm for the determination of the sign solely through the knowledge of ring-components. Our implementation with 128 bits of security delivers a correct result and a probability higher than 1 E-9 in less than 100 milliseconds for 32-bit integers on a laptop.

Metadata

Available format(s): PDF
Category: Public-key cryptography
Publication info: Preprint.
Keywords: Fully homomorphic encryption Bootstrapping Blind rotation Residue Number System Sign determination
Contact author(s): philippe chartier @ raveltech io
michel koskas @ raveltech io
mohammed lemou @ raveltech io
florian mehats @ raveltech io
History: 2024-06-12: revised; 2024-02-02: received; See all versions
Short URL: https://ia.cr/2024/156
License: CC BY

BibTeX

@misc{cryptoeprint:2024/156,
      author = {Philippe Chartier and Michel Koskas and Mohammed Lemou and Florian Méhats},
      title = {Homomorphic sign evaluation with a {RNS} representation of integers},
      howpublished = {Cryptology {ePrint} Archive, Paper 2024/156},
      year = {2024},
      url = {https://eprint.iacr.org/2024/156}
}