Paper 2023/426
A Tightly Secure Identity-based Signature Scheme from Isogenies
Abstract
We present a tightly secure identity-based signature (IBS) scheme based on the supersingular isogeny problems. Although Shaw and Dutta proposed an isogeny-based IBS scheme with provable security, the security reduction is non-tight. For an IBS scheme with concrete security, the tightness of its security reduction affects the key size and signature size. Hence, it is reasonable to focus on a tight security proof for an isogeny-based IBS scheme. In this paper, we propose an isogeny-based IBS scheme based on the lossy CSI-FiSh signature scheme and give a tight security reduction for this scheme. While the existing isogeny-based IBS has the square-root advantage loss in the security proof, the security proof for our IBS scheme avoids such advantage loss, due to the properties of lossy CSI-FiSh.
Metadata
- Available format(s)
- Category
- Public-key cryptography
- Publication info
- Preprint.
- Keywords
- Identity-based signaturesIsogeny-based cryptographyPost-quantum cryptography
- Contact author(s)
-
jo-hyungrok-xz @ ynu ac jp
sato-shingo-zk @ ynu ac jp
shikata-junji-rb @ ynu ac jp - History
- 2023-03-24: approved
- 2023-03-24: received
- See all versions
- Short URL
- https://ia.cr/2023/426
- License
-
CC0
BibTeX
@misc{cryptoeprint:2023/426, author = {Hyungrok Jo and Shingo Sato and Junji Shikata}, title = {A Tightly Secure Identity-based Signature Scheme from Isogenies}, howpublished = {Cryptology {ePrint} Archive, Paper 2023/426}, year = {2023}, url = {https://eprint.iacr.org/2023/426} }