An upper bound on the decryption failure rate of static-key NewHope

John M.  Schanck

Paper 2020/326

An upper bound on the decryption failure rate of static-key NewHope

John M. Schanck

Abstract

We give a new proof that the decryption failure rate of NewHope512 is at most $2^{-398.8}$. As in previous work, this failure rate is with respect to random, honestly generated, secret key and ciphertext pairs. However, our technique can also be applied to a fixed secret key. We demonstrate our technique on some subsets of the NewHope1024 key space, and we identify a large subset of NewHope1024 keys with failure rates of no more than $2^{-439.5}$.

Metadata

Available format(s): PDF
Publication info: Preprint. MINOR revision.
Contact author(s): jschanck @ uwaterloo ca
History: 2020-03-17: received
Short URL: https://ia.cr/2020/326
License: CC BY

BibTeX

@misc{cryptoeprint:2020/326,
      author = {John M.  Schanck},
      title = {An upper bound on the decryption failure rate of static-key NewHope},
      howpublished = {Cryptology ePrint Archive, Paper 2020/326},
      year = {2020},
      note = {\url{https://eprint.iacr.org/2020/326}},
      url = {https://eprint.iacr.org/2020/326}
}