Accelerating Secure (2+1)-Party Computation by Insecure but Efficient Building Blocks. - Keitaro Hiwatashi; Ken Ogura; Satsuya Ohata; Koji Nuida (AsiaCCS, 2021)

An Efficient Secure Division Protocol Using Approximate Multi-Bit Product and New Constant-Round Building Blocks. - Keitaro Hiwatashi; Satsuya Ohata; Koji Nuida (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2022)

Explicit and Nearly Tight Lower Bound for 2-Party Perfectly Secure FSS. - Keitaro Hiwatashi; Koji Nuida (ACNS, 2023)

Exponential Correlated Randomness Is Necessary in Communication-Optimal Perfectly Secure Two-Party Computation. - Keitaro Hiwatashi; Koji Nuida (ITC, 2023)

Correlated Randomness Reduction in Domain-Restricted Secure Two-Party Computation. - Keitaro Hiwatashi; Koji Nuida (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2024)

Negative Results on Information-Theoretic Additive Randomized Encodings. - Keitaro Hiwatashi (ACNS (2), 2025)

Lower Bounds on the Bottleneck Complexity of Secure Multiparty Computation. - Reo Eriguchi; Keitaro Hiwatashi (IACR Cryptol. ePrint Arch., 2025)