Paper 2024/1765
Compact and Tightly Secure (Anonymous) IBE from Module LWE in the QROM
, Yokohama National University, Yokohama National UniversityAbstract
We present a new compact and tightly secure (anonymous) identity-based encryption (IBE) scheme based on structured lattices. This is the first IBE scheme that is (asymptotically) as compact as the most practical NTRU-based schemes and tightly secure under the module learning with errors (MLWE) assumption, known as the standard lattice assumption, in the (quantum) random oracle model. In particular, our IBE scheme is the most compact lattice-based scheme (except for NTRU-based schemes). We design our IBE scheme by instantiating the framework of Gentry, Peikert, and Vaikuntanathan (STOC`08) using the compact trapdoor proposed by Yu, Jia, and Wang (CRYPTO'23). The tightness of our IBE scheme is achieved by extending the proof technique of Katsumata et al. (ASIACRYPT'18, JoC'21) to the hermit normal form setting. To achieve this, we developed some new results on module lattices that may be of independent interest.
Metadata
- Available format(s)
-
PDF
- Category
- Public-key cryptography
- Publication info
- Preprint.
- Keywords
- Identity-Based EncryptionLattice-Based CryptographyTight SecurityAnonymity
- Contact author(s)
-
tomita-toi-sk @ ynu ac jp
shikata-junji-rb @ ynu ac jp - History
- 2024-10-31: revised
- 2024-10-30: received
- See all versions
- Short URL
- https://ia.cr/2024/1765
- License
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CC0
BibTeX
@misc{cryptoeprint:2024/1765,
author = {Toi Tomita and Junji Shikata},
title = {Compact and Tightly Secure (Anonymous) {IBE} from Module {LWE} in the {QROM}},
howpublished = {Cryptology {ePrint} Archive, Paper 2024/1765},
year = {2024},
url = {https://eprint.iacr.org/2024/1765}
}
