POKEx: Performance analysis of POKE-key exchange and SIDH-variants

Computer Science > Cryptography and Security [Submitted on 7 Aug 2026] POKEx: Performance analysis of POKE-key exchange and SIDH-variants Hyeonhak Kim, Suhri Kim In this paper, we present a comparative performance analysis of the POKE-based key exchange and SIDH variants. SIDH gained attention for its small key size and efficient performance, and has been selected as an alternate candidate in NIST PQC Round 4. However, following the key recovery attack by Castryck and Decru in 2022, SIDH was shown to be vulnerable to polynomial-time attacks on classical computers, undermining its security and removing it from consideration. Given that SIDH was regarded as the leading isogeny-based algorithm, several countermeasures, such as MSIDH, MD-SIDH, and bin/terSIDH have been proposed. However, these approaches still face performance limitations. Meanwhile, POKE, proposed by Basso and Maino at Eurocrypt 2025, is an isogeny-based public key encryption scheme that combines a SIDH-like protocol with higher-dimensional isogenies and has drawn attention for its efficient performance. In this work, we adapt POKE into a key exchange algorithm and benchmark it against M-SIDH, terSIDH, and CSIDH. Targeting NIST security level 1, POKE-based KEM is approximately 21.21 times faster than terSIDH and 64.97 times faster than CSIDH, showing that the POKE-based KEM is currently the most promising isogeny-based key exchange candidate. Comments: This work has been published in IEEE Access Subjects: Cryptography and Security (cs.CR) Cite as: arXiv:2608.06826 [cs.CR]   (or arXiv:2608.06826v1 [cs.CR] for this version)   https://doi.org/10.48550/arXiv.2608.06826 Focus to learn more Journal reference: IEEE Access, vol. 14, pp. 19713-19721, 2026 Related DOI: https://doi.org/10.1109/ACCESS.2026.3660893 Focus to learn more Submission history From: Hyeonhak Kim [view email] [v1] Fri, 7 Aug 2026 05:36:59 UTC (185 KB) Access Paper: HTML (experimental) view license Current browse context: cs.CR < prev   |   next > new | recent | 2026-08 Change to browse by: cs References & Citations NASA ADS Google Scholar Semantic Scholar Export BibTeX Citation Bookmark Bibliographic Tools Bibliographic and Citation Tools Bibliographic Explorer Toggle Bibliographic Explorer (What is the Explorer?) Connected Papers Toggle Connected Papers (What is Connected Papers?) Litmaps Toggle Litmaps (What is Litmaps?) scite.ai Toggle scite Smart Citations (What are Smart Citations?) Code, Data, Media Demos Related Papers About arXivLabs Which authors of this paper are endorsers? | Disable MathJax (What is MathJax?)