Paper 2023/767
LFHE: Fully Homomorphic Encryption with Bootstrapping Key Size Less than a Megabyte
Abstract
Fully Homomorphic Encryption (FHE) enables computations to be performed on encrypted data, so one can outsource computations of confidential information to an untrusted party. Ironically, FHE requires the client to generate massive evaluation keys and transfer them to the server side where all computations are supposed to be performed. In this paper, we propose LFHE, the Light-key FHE variant of the FHEW scheme introduced by Ducas and Micciancio in Eurocrypt 2015, and its improvement TFHE scheme proposed by Chillotti et al. in Asiacrypt 2016. In the proposed scheme the client generates small packed evaluation keys, which can be transferred to the server side with much smaller communication overhead compared to the original non-packed variant. The server employs a key reconstruction technique to obtain the evaluation keys needed for computations. This approach allowed us to achieve the FHE scheme with the packed evaluation key transferring size of less than a Megabyte, which is an order of magnitude improvement compared to the best-known methods.
Metadata
- Available format(s)
-
PDF
- Category
- Cryptographic protocols
- Publication info
- Preprint.
- Keywords
- Fully Homomorphic EncryptionBootstrapping
- Contact author(s)
-
kimandr kz @ gmail com
yongwoo @ inha ac kr
max deriabin @ samsung com
jieun eom @ samsung com
rakyong choi @ samsung com - History
- 2023-05-30: approved
- 2023-05-26: received
- See all versions
- Short URL
- https://ia.cr/2023/767
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2023/767,
author = {Andrey Kim and Yongwoo Lee and Maxim Deryabin and Jieun Eom and Rakyong Choi},
title = {{LFHE}: Fully Homomorphic Encryption with Bootstrapping Key Size Less than a Megabyte},
howpublished = {Cryptology {ePrint} Archive, Paper 2023/767},
year = {2023},
url = {https://eprint.iacr.org/2023/767}
}