Paper 2019/398 Original: eprint.iacr.org/2019/398 ↗
Constant-Round Group Key Exchange from the Ring-LWE Assumption
Abstract
Group key-exchange protocols allow a set of N parties to agree on a shared, secret key by communicating over a public network. A number of solutions to this problem have been proposed over the years, mostly based on variants of Diffie-Hellman (two-party) key exchange. There has been relatively little work, however, looking at candidate post-quantum group key-exchange protocols. Here, we propose a constant-round protocol for unauthenticated group key exchange (i.e., with security against a passive eavesdropper) based on the hardness of the Ring-LWE problem. By applying the Katz-Yung compiler using any post-quantum signature scheme, we obtain a (scalable) protocol for authenticated group key exchange with post-quantum security. Our protocol is constructed by generalizing the Burmester-Desmedt protocol to the Ring-LWE setting, which requires addressing several technical challenges.
Metadata
- Available format(s)
PDF- Category
- Public-key cryptography
- Publication info
- Preprint.
- History
- 2019-06-06: last updated
- 2019-04-18: published
- Short URL
- https://ia.cr/2019/398
- License
- https://creativecommons.org/licenses/by/4.0/
BibTeX
@misc{cryptoeprint:2019/398,
author = {Daniel Apon and Dana Dachman-Soled and Huijing Gong and Jonathan Katz},
title = {Constant-Round Group Key Exchange from the Ring-LWE Assumption},
howpublished = {Cryptology {ePrint} Archive, Paper 2019/398},
year = {2019},
url = {https://eprint.iacr.org/2019/398}
}