I’m a research scientist at NTT Social Informatics Laboratories in Japan. My main research area is cryptography, though I am broadly interested in information security and theoretical computer science. My research focuses on how to protect computer program while preserving its functionality, how to achieve secure computation without leaking information, and designing efficient and versatile cryptographic building blocks. More specific topics are
- Program Obfuscation/Watermarking/Copy-Protection
- Functional Encryption
- Lattice-Based Cryptography
- Quantum Cryptography
Recent activities
- May. 2025. A paper on secure key leasing was accepted by CRYPTO 2025.
- Feb. 2025. A paper on non-committing IBE was accepted by PKC 2025.
- Feb. 2025. A paper on watermarking is public on eprint.
- Feb. 2025. A paper on secure key leasing is public on eprint.
- Dec. 2024. Invited to be a speaker at 2025 EIMS-KMS International Workshop on Cryptography
- Dec. 2024. Invited to be a PC member of TCC 2025.
Contact Information
- Please send official invitation mails (PC members, invited talks, etc.) to
firstname dot lastname at ntt dot com (firstname = ryo) - For other mails (review requests etc.) :
- firstname at lastname dot info
- firstname dot lastname at gmail dot com
- Address: NTT Corporation
3-9-11 Midoricho, Musashino-shi, Tokyo 180-8585 Japan
Short Bio.
- Visiting professor at School of Computing at Tokyo Institute of Technology from 04/2024 -
- Visiting associate professor at School of Computing at Tokyo Institute of Technology from 07/2016 to 03/2024
- Visiting researcher at Northeastern University at Boston during Oct. 2014 - Dec. 2015 (hosted by Daniel Wichs)
- Obtained my Dr. Sci. (corresponding to Ph.D.) from Tokyo Institute of Technology in September 2010 (adviser: Keisuke Tanaka)
- Joined NTT Information Sharing Platform Laboratories (now, NTT Social Informatics Laboratories) in 2007
- Completed my Master’s degree in Informatics at Graduate School of Informatics Kyoto University in 2007
- Completed my Bachelor’s degree in Engineering at Kyoto University in 2005
On pronunciation of my first name
I do not know English words whose pronunciation are exactly the same as that of Ryo. The pronunciation of Rio, which is the name of a city in Brazil, is similar to that of Ryo.