Paper 2024/018
Smaller Sphincs$^{+}$
, Cisco Systems, National Institute of Standards and TechnologyAbstract
NIST published FIPS 205 based on the specification of Sphincs$^{+}$. A formula to determine the security strength of a given parameter set is listed in SPHINCSsubmission31. It is quite complex to use that formula to get the security degradation behavior based on different increases in the number of signatures (called $2^{m}$ in this paper) per signing key. The task would become even more complex when we need to compare the security degradation characteristics of many parameter sets. In this paper, we provide a simpler formula to determine the security strengths of a given parameter set at various numbers of signatures produced by one signing key. With this new formula, the task of comparing parameter sets, especially, their security degradation characteristics become easy and that allowed us to search for best parameter sets for users to consider to use and for standard bodies to consider for standardization.
Note: We had a miscalculation of the cost of the FORS trees in the searches of the parameter sets discussed in the previous versions. Therefore, we updated our search program and ran new searches. This new version provides those new search results. We also took the opportunity to improve and expand various discussions about Smaller Sphincs$^{+}$.
Metadata
- Available format(s)
-
PDF
- Category
- Public-key cryptography
- Publication info
- Preprint.
- Keywords
- Postquantum SignaturesSphincs+SLH-DSAFIPS 205Stateless Hash-based Signatures
- Contact author(s)
-
sfluhrer @ cisco com
quynh dang @ nist gov - History
- 2025-01-16: last of 2 revisions
- 2024-01-05: received
- See all versions
- Short URL
- https://ia.cr/2024/018
- License
-
CC0
BibTeX
@misc{cryptoeprint:2024/018,
author = {Scott Fluhrer and Quynh Dang},
title = {Smaller Sphincs$^{+}$},
howpublished = {Cryptology {ePrint} Archive, Paper 2024/018},
year = {2024},
url = {https://eprint.iacr.org/2024/018}
}
