Paper 2024/1505

FINALLY: A Multi-Key FHE Scheme Based on NTRU and LWE

Jeongeun Park, Norwegian University of Science and Technology
Barry Van Leeuwen, KU Leuven
Oliver Zajonc, KU Leuven
Abstract

Multi-key fully homomorphic encryption (MKFHE), a generalization of fully homomorphic encryption (FHE), enables a computation over encrypted data under multiple keys. The first MKFHE schemes were based on the NTRU primitive, however these early NTRU based FHE schemes were found to be insecure due to the problem of over-stretched parameters. Recently, in the case of standard (non-multi key) FHE a secure version, called FINAL, of NTRU has been found. In this work we extend FINAL to an MKFHE scheme, this allows us to benefit from some of the performance advantages provided by NTRU based primitives. Thus, our scheme provides competitive performance against current state-of-the-art multi-key TFHE, in particular reducing the computational complexity from quadratic to linear in the number of keys.

Metadata
Available format(s)
PDF
Category
Cryptographic protocols
Publication info
Published by the IACR in CIC 2024
Keywords
FHEMulti-key FHELWENTRU
Contact author(s)
jeongeun park @ ntnu no
barry vanleeuwen @ kuleuven be
oliver zajonc @ esat kuleuven be
History
2024-09-30: approved
2024-09-25: received
See all versions
Short URL
https://ia.cr/2024/1505
License
Creative Commons Attribution
CC BY

BibTeX

@misc{cryptoeprint:2024/1505,
      author = {Jeongeun Park and Barry Van Leeuwen and Oliver Zajonc},
      title = {{FINALLY}: A Multi-Key {FHE} Scheme Based on {NTRU} and {LWE}},
      howpublished = {Cryptology {ePrint} Archive, Paper 2024/1505},
      year = {2024},
      url = {https://eprint.iacr.org/2024/1505}
}
Note: In order to protect the privacy of readers, eprint.iacr.org does not use cookies or embedded third party content.