Paper 2016/1157
NewHope without reconciliation
Erdem Alkim, Léo Ducas, Thomas Pöppelmann, and Peter Schwabe
Abstract
In this paper we introduce NewHope-Simple, a variant of the NewHope Ring-LWE-based key exchange that is using a straight-forward transformation from Ring-LWE encryption to a passively secure KEM (or key-exchange scheme). The main advantage of NewHopeLP-Simple over NewHope is simplicity. In particular, it avoids the error-reconciliation mechanism originally proposed by Ding. The explanation of his method, combined with other tricks, like unbiasing the key following Peikert's tweak and using the quantizer $D_4$ to extract one key bit from multiple coefficients, takes more than three pages in the NewHope-Simple paper. The price for that simplicity is small: one of the exchanged messages increases in size by $6.25\%$ from $2048$ bytes to $2176$ bytes. The security of NewHopeLP is the same as the security of NewHope; the performance is very similar.
Note: Added a discussion about concurrent related work by Jin and Zhao
Metadata
- Available format(s)
-
PDF
- Category
- Public-key cryptography
- Publication info
- Preprint. MINOR revision.
- Keywords
- Post-quantum key exchangeNewHopecode simplicity
- Contact author(s)
- newhope @ cryptojedi org
- History
- 2017-11-09: revised
- 2016-12-21: received
- See all versions
- Short URL
- https://ia.cr/2016/1157
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2016/1157,
author = {Erdem Alkim and Léo Ducas and Thomas Pöppelmann and Peter Schwabe},
title = {{NewHope} without reconciliation},
howpublished = {Cryptology {ePrint} Archive, Paper 2016/1157},
year = {2016},
url = {https://eprint.iacr.org/2016/1157}
}
