Separating Encryption and Key Issuance in Digital Rights Management Systems. - Goichiro Hanaoka; Kazuto Ogawa; Itsuro Murota; Go Ohtake; Keigo Majima; Kimiyuki Oyamada; Seiichi Gohshi; Seiichi Namba; Hideki Imai (ACISP, 2003)

Managing Encryption and Key Publication Independently in Digital Rights Management Systems. - Goichiro Hanaoka; Kazuto Ogawa; Itsuro Murota; Go Ohtake; Keigo Majima; Seiichi Gohshi; Kimiyuki Oyamada; Seiichi Namba; Hideki Imai (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2004)

A secure traitor tracing scheme against key exposure. - Kazuto Ogawa; Goichiro Hanaoka; Hideki Imai (ISIT, 2005)

Adaptively Secure Traitor Tracing Against Key Exposure and Its Application to Anywhere TV Service. - Kazuto Ogawa; Goichiro Hanaoka; Hideki Imai (ACISP, 2006)

Flexible License Transfer System Using Mobile Terminal. - Masaki Inamura; Toshiaki Tanaka; Toshiyuki Fujisawa; Kazuto Ogawa; Takeshi Kimura (SECRYPT, 2006)

An Improvement of Tardos's Collusion-Secure Fingerprinting Codes with Very Short Lengths. - Koji Nuida; Satoshi Fujitsu; Manabu Hagiwara; Takashi Kitagawa; Hajime Watanabe; Kazuto Ogawa; Hideki Imai (AAECC, 2007)

A Tracing Algorithm for Short 2-Secure Probabilistic Fingerprinting Codes Strongly Protecting Innocent Users. - Satoshi Fujitsu; Koji Nuida; Manabu Hagiwara; Takashi Kitagawa; Hajime Watanabe; Kazuto Ogawa; Hideki Imai (CCNC, 2007)

Trade-Off Traitor Tracing. - Kazuto Ogawa; Go Ohtake; Goichiro Hanaoka; Hideki Imai (INDOCRYPT, 2007)

Anonymous Authentication Scheme for Subscription Services. - Arisa Fujii; Go Ohtake; Goichiro Hanaoka; Kazuto Ogawa (KES (3), 2007)

Anonymous Pay-TV System with Secure Revenue Sharing. - Kazuto Ogawa; Goichiro Hanaoka; Kazukuni Kobara; Kanta Matsuura; Hideki Imai (KES (3), 2007)

Anonymous Prepaid Content Viewing System with Mobile Terminal. - Toshiyuki Fujisawa; Kazuto Ogawa; Takeshi Kimura; Masaki Inamura; Toshiaki Tanaka (SECRYPT, 2007)

Traitor Tracing Scheme Secure against Adaptive Key Exposure and its Application to Anywhere TV Service. - Kazuto Ogawa; Goichiro Hanaoka; Hideki Imai (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2007)

Extension of Broadcasting Service by Using Electronic Tokens. - Kazuto Ogawa; Goichiro Hanaoka; Hideki Imai (IEICE Trans. Inf. Syst., 2007)

An Efficient Strong Key-Insulated Signature Scheme and Its Application. - Go Ohtake; Goichiro Hanaoka; Kazuto Ogawa (EuroPKI, 2008)

Chosen Ciphertext Secure Public Key Encryption with a Simple Structure. - Goichiro Hanaoka; Hideki Imai; Kazuto Ogawa; Hajime Watanabe (IWSEC, 2008)

On the Theoretical Gap between Group Signatures with and without Unlinkability. - Go Ohtake; Arisa Fujii; Goichiro Hanaoka; Kazuto Ogawa (AFRICACRYPT, 2009)

An improvement of discrete Tardos fingerprinting codes. - Koji Nuida; Satoshi Fujitsu; Manabu Hagiwara; Takashi Kitagawa; Hajime Watanabe; Kazuto Ogawa; Hideki Imai (Des. Codes Cryptogr., 2009)

An Efficient 2-Secure and Short Random Fingerprint Code and Its Security Evaluation. - Koji Nuida; Satoshi Fujitsu; Manabu Hagiwara; Hideki Imai; Takashi Kitagawa; Kazuto Ogawa; Hajime Watanabe (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2009)

A Trade-off Traitor Tracing Scheme. - Go Ohtake; Kazuto Ogawa; Goichiro Hanaoka; Hideki Imai (IEICE Trans. Inf. Syst., 2009)

Efficient Broadcast Encryption with Personalized Messages. - Go Ohtake; Goichiro Hanaoka; Kazuto Ogawa (ProvSec, 2010)

Efficient Provider Authentication for Bidirectional Broadcasting Service. - Go Ohtake; Goichiro Hanaoka; Kazuto Ogawa (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2010)

Application Authentication for Hybrid Services of Broadcasting and Communications Networks. - Go Ohtake; Kazuto Ogawa (WISA, 2011)

Secure Broadcast System with Simultaneous Individual Messaging. - Arisa Fujii; Go Ohtake; Goichiro Hanaoka; Nuttapong Attrapadung; Hajime Watanabe; Kazuto Ogawa; Hideki Imai (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2011)

Weakened Anonymity of Group Signature and Its Application to Subscription Services. - Kazuto Ogawa; Go Ohtake; Arisa Fujii; Goichiro Hanaoka (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2014)

Practically secure update of scrambling scheme. - Kazuto Ogawa; Tomoyuki Inoue (BMSB, 2015)

Watermarking for HEVC/H.265 stream. - Kazuto Ogawa; Go Ohtake (ICCE, 2015)

Privacy preserving system for integrated broadcast-broadband services. - Go Ohtake; Kazuto Ogawa (ICCE, 2015)

Content and Key Management to Trace Traitors in Broadcasting Services. - Kazuto Ogawa; Goichiro Hanaoka; Hideki Imai (STM, 2015)

Privacy preserving system for integrated broadcast-broadband services using attribute-based encryption. - Go Ohtake; Kazuto Ogawa; Reihaneh Safavi-Naini (IEEE Trans. Consumer Electron., 2015)

Application Authentication System with Efficiently Updatable Signature. - Kazuto Ogawa; Go Ohtake (IEICE Trans. Inf. Syst., 2016)

Key Management for Versatile Pay-TV Services. - Kazuto Ogawa; Sakurako Tamura; Goichiro Hanaoka (STM, 2017)

How to Make Traitor Tracing Schemes Secure against a Content Comparison Attack in Actual Services. - Kazuto Ogawa; Goichiro Hanaoka; Hideki Imai (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2017)

Partially Wildcarded Ciphertext-Policy Attribute-Based Encryption and Its Performance Evaluation. - Go Ohtake; Kazuto Ogawa; Goichiro Hanaoka; Shota Yamada 001; Kohei Kasamatsu; Takashi Yamakawa; Hideki Imai (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2017)

Attribute-Based Encryption for Range Attributes. - Nuttapong Attrapadung; Goichiro Hanaoka; Kazuto Ogawa; Go Ohtake; Hajime Watanabe; Shota Yamada 001 (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2018)

Foreword. - Kazuto Ogawa (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2018)

Privacy Preserving System for Real-Time Enriched-Integrated Service with Feedback to Providers. - Kaisei Kajita; Kazuto Ogawa; Go Ohtake (HCI (29), 2019)

Privacy Preservation for Versatile Pay-TV Services. - Kazuto Ogawa; Koji Nuida (HCI (29), 2019)

Short Lattice Signatures in the Standard Model with Efficient Tag Generation. - Kaisei Kajita; Kazuto Ogawa; Koji Nuida; Tsuyoshi Takagi (ProvSec, 2020)

A Constant-Size Signature Scheme with a Tighter Reduction from the CDH Assumption. - Kaisei Kajita; Kazuto Ogawa; Eiichiro Fujisaki (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2020)

Output Prediction Attacks on SPN Block Ciphers using Deep Learning. - Hayato Kimura 002; Keita Emura; Takanori Isobe 001; Ryoma Ito 001; Kazuto Ogawa; Toshihiro Ohigashi (IACR Cryptol. ePrint Arch., 2021)

Privacy-Preserving System for Enriched-Integrated Service. - Kaisei Kajita; Go Ohtake; Kazuto Ogawa (IEICE Trans. Inf. Syst., 2021)

Output Prediction Attacks on Block Ciphers Using Deep Learning. - Hayato Kimura 002; Keita Emura; Takanori Isobe 001; Ryoma Ito 001; Kazuto Ogawa; Toshihiro Ohigashi (ACNS Workshops, 2022)

Membership Privacy for Asynchronous Group Messaging. - Keita Emura; Kaisei Kajita; Ryo Nojima; Kazuto Ogawa; Go Ohtake (IACR Cryptol. ePrint Arch., 2022)

Continuous Group Key Agreement with Flexible Authorization and Its Applications. - Kaisei Kajita; Keita Emura; Kazuto Ogawa; Ryo Nojima; Go Ohtake (IACR Cryptol. ePrint Arch., 2022)

Providing Membership Privacy to the Asynchronous Ratcheting Trees Protocol without losing Scalability. - Keita Emura; Kaisei Kajita; Ryo Nojima; Kazuto Ogawa; Go Ohtake (J. Wirel. Mob. Networks Ubiquitous Comput. Dependable Appl., 2022)

A Deeper Look into Deep Learning-based Output Prediction Attacks Using Weak SPN Block Ciphers. - Hayato Kimura 002; Keita Emura; Takanori Isobe 001; Ryoma Ito 001; Kazuto Ogawa; Toshihiro Ohigashi (J. Inf. Process., 2023)

Short Lattice Signature Scheme with Tighter Reduction under Ring-SIS Assumption. - Kaisei Kajita; Go Ohtake; Kazuto Ogawa; Koji Nuida; Tsuyoshi Takagi (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2023)