Paper 2024/1306
Scloud+: a Lightweight LWE-based KEM without Ring/Module Structure
Abstract
We present Scloud+, an LWE-based key encapsulation mechanism (KEM). The key feature of Scloud+ is its use of the unstructured-LWE problem (i.e., without algebraic structures such as rings or modules) and its incorporation of ternary secrets and lattice coding to enhance performance. A notable advantage of the unstructured-LWE problem is its resistance to potential attacks exploiting algebraic structures, making it a conservative choice for constructing high-security schemes. However, a key disadvantage of such schemes is their limited computational and communication efficiency. Scloud+ utilizes ternary secrets and $\text{BW}_{32}$ lattice codes to enhance noise control and ensure robust error correction during decryption, enabling smaller parameters while maintaining low decryption failure probabilities. Equipped with these techniques, Scloud+ exhibits a significant improvement in efficiency. When compared with FrodoKEM for parameter sets targeting 128, 192, and 256 bits of security respectively, \lsc achieves practical performance with a public key size approximately $0.71 \sim 0.87$x and a ciphertext size approximately $0.56 \sim 0.78$x that of FrodoKEM. The encapsulation plus decapsulation time is approximately $0.74 \sim 0.77$x that of FrodoKEM.
Metadata
- Available format(s)
- Category
- Public-key cryptography
- Publication info
- Published elsewhere. Minor revision. SSR 2024
- Keywords
- post-quantum cryptographykey encapsulation mechanismlearning with errorslattice codeBarnes-Wall lattice
- Contact author(s)
-
anyuwang @ tsinghua edu cn
zhengzx @ cuc edu cn
zhaochunhuan @ huawei com
qiuzhiyuan @ sdibc cn
zengguang13 @ huawei com
yuanye44 @ huawei com
mchangchun @ pbc gov cn
xiaoyunwang @ tsinghua edu cn - History
- 2024-11-30: revised
- 2024-08-21: received
- See all versions
- Short URL
- https://ia.cr/2024/1306
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2024/1306, author = {Anyu Wang and Zhongxiang Zheng and Chunhuan Zhao and Zhiyuan Qiu and Guang Zeng and Ye Yuan and Changchun Mu and Xiaoyun Wang}, title = {Scloud+: a Lightweight {LWE}-based {KEM} without Ring/Module Structure}, howpublished = {Cryptology {ePrint} Archive, Paper 2024/1306}, year = {2024}, url = {https://eprint.iacr.org/2024/1306} }