Universally Composable Identity-Based Encryption. - Ryo Nishimaki; Yoshifumi Manabe; Tatsuaki Okamoto (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2008)

Security on Hybrid Encryption with the Tag-KEM/DEM Framework. - Toshihide Matsuda; Ryo Nishimaki; Akira Numayama; Keisuke Tanaka (ACISP, 2009)

On the Insecurity of the Fiat-Shamir Signatures with Iterative Hash Functions. - Eiichiro Fujisaki; Ryo Nishimaki; Keisuke Tanaka (ProvSec, 2009)

Efficient Non-interactive Universally Composable String-Commitment Schemes. - Ryo Nishimaki; Eiichiro Fujisaki; Keisuke Tanaka (ProvSec, 2009)

CCA Proxy Re-Encryption without Bilinear Maps in the Standard Model. - Toshihide Matsuda; Ryo Nishimaki; Keisuke Tanaka (Public Key Cryptography, 2010)

An Efficient Non-interactive Universally Composable String-Commitment Scheme. - Ryo Nishimaki; Eiichiro Fujisaki; Keisuke Tanaka (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2012)

A Multi-Trapdoor Commitment Scheme from the RSA Assumption. - Ryo Nishimaki; Eiichiro Fujisaki; Keisuke Tanaka (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2012)

Universally composable adaptive oblivious transfer (with access control) from standard assumptions. - Masayuki Abe; Jan Camenisch; Maria Dubovitskaya; Ryo Nishimaki (Digital Identity Management, 2013)

How to Watermark Cryptographic Functions. - Ryo Nishimaki (IACR Cryptol. ePrint Arch., 2014)

Verifiably encrypted signatures with short keys based on the decisional linear problem and obfuscation for encrypted VES. - Ryo Nishimaki; Keita Xagawa (Des. Codes Cryptogr., 2015)

Tagged One-Time Signatures: Tight Security and Optimal Tag Size. - Masayuki Abe; Bernardo David; Markulf Kohlweiss; Ryo Nishimaki; Miyako Ohkubo (IACR Cryptol. ePrint Arch., 2015)

Re-encryption, functional re-encryption, and multi-hop re-encryption: A framework for achieving obfuscation-based security and instantiations from lattices. - Nishanth Chandran; Melissa Chase; Feng-Hao Liu; Ryo Nishimaki; Keita Xagawa (IACR Cryptol. ePrint Arch., 2015)

Generalizing Efficient Multiparty Computation. - Bernardo David; Ryo Nishimaki; Samuel Ranellucci; Alain Tapp (IACR Cryptol. ePrint Arch., 2015)

Watermarking Cryptographic Programs Against Arbitrary Removal Strategies. - Ryo Nishimaki; Daniel Wichs (IACR Cryptol. ePrint Arch., 2015)

Anonymous Traitor Tracing: How to Embed Arbitrary Information in a Key. - Ryo Nishimaki; Daniel Wichs; Mark Zhandry (IACR Cryptol. ePrint Arch., 2015)

Post-Challenge Leakage Resilient Public-Key Cryptosystem in Split State Model. - Eiichiro Fujisaki; Akinori Kawachi; Ryo Nishimaki; Keisuke Tanaka; Kenji Yasunaga (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2015)

Key-Private Proxy Re-Encryption from Lattices, Revisited. - Ryo Nishimaki; Keita Xagawa (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2015)

Watermarking Cryptographic Programs. - Ryo Nishimaki (Mycrypt, 2016)

Constant-Size Structure-Preserving Signatures: Generic Constructions and Simple Assumptions. - Masayuki Abe; Melissa Chase; Bernardo David; Markulf Kohlweiss; Ryo Nishimaki; Miyako Ohkubo (J. Cryptol., 2016)

Indistinguishability Obfuscation: Simpler Constructions using Secret-Key Functional Encryption. - Fuyuki Kitagawa; Ryo Nishimaki; Keisuke Tanaka (IACR Cryptol. ePrint Arch., 2017)

Indistinguishability Obfuscation for All Circuits from Secret-Key Functional Encryption. - Fuyuki Kitagawa; Ryo Nishimaki; Keisuke Tanaka (IACR Cryptol. ePrint Arch., 2017)

From Single-Key to Collusion-Resistant Secret-Key Functional Encryption by Leveraging Succinctness. - Fuyuki Kitagawa; Ryo Nishimaki; Keisuke Tanaka (IACR Cryptol. ePrint Arch., 2017)

Constrained PRFs for mathrmNC^1 in Traditional Groups. - Nuttapong Attrapadung; Takahiro Matsuda 002; Ryo Nishimaki; Shota Yamada 001; Takashi Yamakawa (CRYPTO (2), 2018)

Constrained PRFs for NC1 in Traditional Groups. - Nuttapong Attrapadung; Takahiro Matsuda 002; Ryo Nishimaki; Shota Yamada 001; Takashi Yamakawa (IACR Cryptol. ePrint Arch., 2018)

Adaptively Single-Key Secure Constrained PRFs for NC1. - Nuttapong Attrapadung; Takahiro Matsuda 002; Ryo Nishimaki; Shota Yamada 001; Takashi Yamakawa (IACR Cryptol. ePrint Arch., 2018)

Constrained PRFs for Bit-fixing from OWFs with Constant Collusion Resistance. - Alex Davidson; Shuichi Katsumata; Ryo Nishimaki; Shota Yamada 001 (IACR Cryptol. ePrint Arch., 2018)

A Bit-fixing PRF with O(1) Collusion-Resistance from LWE. - Alex Davidson; Ryo Nishimaki (IACR Cryptol. ePrint Arch., 2018)

Universal Proxy Re-Encryption. - Nico Döttling; Ryo Nishimaki (IACR Cryptol. ePrint Arch., 2018)

Adaptively Secure and Succinct Functional Encryption: Improving Security and Efficiency, Simultaneously. - Fuyuki Kitagawa; Ryo Nishimaki; Keisuke Tanaka; Takashi Yamakawa (IACR Cryptol. ePrint Arch., 2018)

Watermarking Cryptographic Capabilities. - Aloni Cohen; Justin Holmgren; Ryo Nishimaki; Vinod Vaikuntanathan; Daniel Wichs (SIAM J. Comput., 2018)

Adaptively Single-Key Secure Constrained PRFs for mathrm NC^1. - Nuttapong Attrapadung; Takahiro Matsuda 002; Ryo Nishimaki; Shota Yamada 001; Takashi Yamakawa (Public Key Cryptography (2), 2019)

Exploring Constructions of Compact NIZKs from Various Assumptions. - Shuichi Katsumata; Ryo Nishimaki; Shota Yamada 001; Takashi Yamakawa (IACR Cryptol. ePrint Arch., 2019)

Designated Verifier/Prover and Preprocessing NIZKs from Diffie-Hellman Assumptions. - Shuichi Katsumata; Ryo Nishimaki; Shota Yamada 001; Takashi Yamakawa (IACR Cryptol. ePrint Arch., 2019)

Leakage-resilient Identity-based Encryption in Bounded Retrieval Model with Nearly Optimal Leakage-Ratio. - Ryo Nishimaki; Takashi Yamakawa (IACR Cryptol. ePrint Arch., 2019)

How to Watermark Cryptographic Functions by Bilinear Maps. - Ryo Nishimaki (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2019)

Adaptively Secure Constrained Pseudorandom Functions in the Standard Model. - Alex Davidson; Shuichi Katsumata; Ryo Nishimaki; Shota Yamada 001; Takashi Yamakawa (IACR Cryptol. ePrint Arch., 2020)

Adaptively Secure Inner Product Encryption from LWE. - Shuichi Katsumata; Ryo Nishimaki; Shota Yamada 001; Takashi Yamakawa (IACR Cryptol. ePrint Arch., 2020)

Secure Software Leasing from Standard Assumptions. - Fuyuki Kitagawa; Ryo Nishimaki; Takashi Yamakawa (IACR Cryptol. ePrint Arch., 2020)

Equipping Public-Key Cryptographic Primitives with Watermarking (or: A Hole Is to Watermark). - Ryo Nishimaki (IACR Cryptol. ePrint Arch., 2020)

From Cryptomania to Obfustopia Through Secret-Key Functional Encryption. - Nir Bitansky; Ryo Nishimaki; Alain Passelègue; Daniel Wichs (J. Cryptol., 2020)

Fast, compact, and expressive attribute-based encryption. - Junichi Tomida; Yuto Kawahara; Ryo Nishimaki (Des. Codes Cryptogr., 2021)

Quantum Encryption with Certified Deletion, Revisited: Public Key, Attribute-Based, and Classical Communication. - Taiga Hiroka; Tomoyuki Morimae; Ryo Nishimaki; Takashi Yamakawa (IACR Cryptol. ePrint Arch., 2021)

Certified Everlasting Zero-Knowledge Proof for QMA. - Taiga Hiroka; Tomoyuki Morimae; Ryo Nishimaki; Takashi Yamakawa (IACR Cryptol. ePrint Arch., 2021)

Round-Optimal Blind Signatures in the Plain Model from Classical and Quantum Standard Assumptions. - Shuichi Katsumata; Ryo Nishimaki; Shota Yamada 001; Takashi Yamakawa (IACR Cryptol. ePrint Arch., 2021)

KDM Security for the Fujisaki-Okamoto Transformations in the QROM. - Fuyuki Kitagawa; Ryo Nishimaki (IACR Cryptol. ePrint Arch., 2021)

The Direction of Updatable Encryption Does Matter. - Ryo Nishimaki (IACR Cryptol. ePrint Arch., 2021)

Quantum Encryption with Certified Deletion: Public Key and Attribute-Based. - Ryo Nishimaki; Takashi Yamakawa (IACR Cryptol. ePrint Arch., 2021)

Compact Designated Verifier NIZKs from the CDH Assumption Without Pairings. - Shuichi Katsumata; Ryo Nishimaki; Shota Yamada 001; Takashi Yamakawa (J. Cryptol., 2021)

Simple and Generic Constructions of Succinct Functional Encryption. - Fuyuki Kitagawa; Ryo Nishimaki; Keisuke Tanaka (J. Cryptol., 2021)

Cryptanalysis of Boyen's attribute-based encryption scheme in TCC 2013. - Shweta Agrawal 001; Rajarshi Biswas; Ryo Nishimaki; Keita Xagawa; Xiang Xie; Shota Yamada 001 (Des. Codes Cryptogr., 2022)

Bounded Functional Encryption for Turing Machines: Adaptive Security from General Assumptions. - Shweta Agrawal 001; Fuyuki Kitagawa; Anuja Modi; Ryo Nishimaki; Shota Yamada 001; Takashi Yamakawa (IACR Cryptol. ePrint Arch., 2022)

Certified Everlasting Functional Encryption. - Taiga Hiroka; Tomoyuki Morimae; Ryo Nishimaki; Takashi Yamakawa (IACR Cryptol. ePrint Arch., 2022)

Watermarking PRFs against Quantum Adversaries. - Fuyuki Kitagawa; Ryo Nishimaki (IACR Cryptol. ePrint Arch., 2022)

Functional Encryption with Secure Key Leasing. - Fuyuki Kitagawa; Ryo Nishimaki (IACR Cryptol. ePrint Arch., 2022)

Obfustopia Built on Secret-Key Functional Encryption. - Fuyuki Kitagawa; Ryo Nishimaki; Keisuke Tanaka (J. Cryptol., 2022)

Public Key Encryption with Secure Key Leasing. - Shweta Agrawal 001; Fuyuki Kitagawa; Ryo Nishimaki; Shota Yamada 001; Takashi Yamakawa (IACR Cryptol. ePrint Arch., 2023)

Obfuscation of Pseudo-Deterministic Quantum Circuits. - James Bartusek; Fuyuki Kitagawa; Ryo Nishimaki; Takashi Yamakawa (IACR Cryptol. ePrint Arch., 2023)

Certified Everlasting Secure Collusion-Resistant Functional Encryption, and More. - Taiga Hiroka; Fuyuki Kitagawa; Tomoyuki Morimae; Ryo Nishimaki; Tapas Pal; Takashi Yamakawa (IACR Cryptol. ePrint Arch., 2023)

Robust Combiners and Universal Constructions for Quantum Cryptography. - Taiga Hiroka; Fuyuki Kitagawa; Ryo Nishimaki; Takashi Yamakawa (IACR Cryptol. ePrint Arch., 2023)

Quantum Public-Key Encryption with Tamper-Resilient Public Keys from One-Way Functions. - Fuyuki Kitagawa; Tomoyuki Morimae; Ryo Nishimaki; Takashi Yamakawa (IACR Cryptol. ePrint Arch., 2023)

One-out-of-Many Unclonable Cryptography: Definitions, Constructions, and More. - Fuyuki Kitagawa; Ryo Nishimaki (IACR Cryptol. ePrint Arch., 2023)

Publicly Verifiable Deletion from Minimal Assumptions. - Fuyuki Kitagawa; Ryo Nishimaki; Takashi Yamakawa (IACR Cryptol. ePrint Arch., 2023)

Compact Structure-Preserving Signatures with Almost Tight Security. - Masayuki Abe; Dennis Hofheinz; Ryo Nishimaki; Miyako Ohkubo; Jiaxin Pan 001 (J. Cryptol., 2023)

Untelegraphable Encryption and its Applications. - Jeffrey Champion; Fuyuki Kitagawa; Ryo Nishimaki; Takashi Yamakawa (CoRR, 2024)

Pre-Constrained Cryptography: Broad Definitions, New Constructions, Unbounded Security. - Shweta Agrawal 001; Simran Kumari; Ryo Nishimaki (IACR Cryptol. ePrint Arch., 2024)

A Note on Security Definitions for Secret Sharing with Certified Deletion. - Dominique Bazin; Ryo Nishimaki (IACR Cryptol. ePrint Arch., 2024)

Compact NIZKs from Standard Assumptions on Bilinear Maps. - Shuichi Katsumata; Ryo Nishimaki; Shota Yamada 001; Takashi Yamakawa (J. Cryptol., 2024)

Watermarking PRFs and PKE Against Quantum Adversaries. - Fuyuki Kitagawa; Ryo Nishimaki (J. Cryptol., 2024)

Non-committing Identity Based Encryption: Constructions and Applications. - Rishab Goyal; Fuyuki Kitagawa; Venkata Koppula; Ryo Nishimaki; Mahesh Sreekumar Rajasree; Takashi Yamakawa (PKC (1), 2025)

MicroCrypt Assumptions with Quantum Input Sampling and Pseudodeterminism: Constructions and Separations. - Mohammed Barhoush; Ryo Nishimaki; Takashi Yamakawa (IACR Cryptol. ePrint Arch., 2025)

White-Box Watermarking Signatures against Quantum Adversaries and Its Applications. - Fuyuki Kitagawa; Ryo Nishimaki (IACR Cryptol. ePrint Arch., 2025)

PKE and ABE with Collusion-Resistant Secure Key Leasing. - Fuyuki Kitagawa; Ryo Nishimaki; Nikhil Pappu (IACR Cryptol. ePrint Arch., 2025)