Paper 2026/2119

CKKS Bootstrapping in less than 10ms

Rending Ouyang, Zhejiang University
Jian Liu, Zhejiang University
Peimin Gao, The Hong Kong Polytechnic University
Pan Xiao, Zhejiang University
Heng Zhang, Zhejiang University
Man Ho Au, The Hong Kong Polytechnic University
Cong Zhang, Zhejiang University
Kui Ren, Zhejiang University
Chun Chen, Zhejiang University
Abstract

Bootstrapping enables deep homomorphic computation in CKKS by replenishing multiplicative levels. It remains one of the scheme's most expensive operations. HEAAN reports a bootstrapping latency of 6.97ms, substantially faster than other publicly documented alternatives. However, the algorithmic and implementation techniques underlying this result have not been disclosed, leaving it unclear how such performance is achieved. In this work, we present a fully specified CKKS bootstrapping construction that achieves performance comparable to that reported by HEAAN. Building on SHIP (presented in Eurocrypt 2025), we introduce several algorithmic innovations that reduce communication and computational overhead while enabling efficient parallel execution. Our implementation bootstraps a single complex-valued ciphertext in 8.2ms and achieves an amortized latency of 4.6ms per ciphertext for a batch of 64. These results demonstrate practical sub-10ms CKKS bootstrapping.

Metadata
Available format(s)
PDF
Category
Public-key cryptography
Publication info
Preprint.
Contact author(s)
oyyy @ zju edu cn
liujian2411 @ zju edu cn
peimin-cs gao @ connect polyu hk
pan xiao @ zju edu cn
heng zhang @ zju edu cn
man-ho-allen au @ polyu edu hk
0022090 @ zju edu cn
kuiren @ zju edu cn
chenc @ zju edu cn
History
2026-09-22: approved
2026-09-20: received
See all versions
Short URL
https://ia.cr/2026/2119
License
Creative Commons Attribution
CC BY

BibTeX

@misc{cryptoeprint:2026/2119,
      author = {Rending Ouyang and Jian Liu and Peimin Gao and Pan Xiao and Heng Zhang and Man Ho Au and Cong Zhang and Kui Ren and Chun Chen},
      title = {{CKKS} Bootstrapping in less than 10ms},
      howpublished = {Cryptology {ePrint} Archive, Paper 2026/2119},
      year = {2026},
      url = {https://eprint.iacr.org/2026/2119}
}
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