Details of a Researcher - Moriyama, Koichi

Moriyama, Koichi

写真a

Affiliation: Faculty of Environment and Information Studies ( Shonan Fujisawa )

Position: Professor (Non-tenured)

E-mail Address

Related Websites

https://www.linkedin.com/in/koichi-moriyama-ph-d-92669b23/

Contact Address: 5322 Endo, Suite ΔN210, Fujisawa-shi, Kanagawa 252-0882

External Links

Profile 【 Display / hide 】

After completing his master's degree in Computer Science at the Graduate School of Science and Technology, Keio University, he joined Sony Corporation. He worked at NTT DOCOMO, Inc. (on secondment), Sony Ericsson Mobile Communications Inc., and DOCOMO's Silicon Valley office before starting the FIDO authentication project at the Product Department in July 2014. He became a board member of the FIDO Alliance in May 2015, chair of the FIDO Japan WG in October 2016, a member of the Executive Council (Director) in January 2019, and a Director of W3C, Inc. in October 2022. He has accumulated experience in evolving software and mobile technology and drives open innovations from mobile devices. From July 2020, he focused on security services and their digital identity platform, and from July 2022, he became Chief Security Architect at NTT DOCOMO. In February 2022, he began academic research on Sybil-Resistant Self-Sovereign Identity Based on Attested Execution Secure Processors, and he completed his doctoral program at the Graduate School, Institute of Information Security, and obtained a Ph.D. degree in Informatics in March 2025. In April 2026, he was appointed as a Professor (Non-tenured) at the Faculty of Environmental Information, Keio University.

Message from the Faculty Member 【 Display / hide 】

Focusing on trust and security architecture for the digital age and its deployment strategy, we aim to address social issues from the users' perspective, based on internet, mobile, and device technologies, so that people can live safely in an increasingly unstable society. "Digital identity" plays a significant role in this. We will face head-on the difficult task of simultaneously satisfying different, often conflicting requirements. Continuing to change and respecting diversity will enrich our imaginations in fun ways. We will solve the challenges we face together and create and protect the digital society of the future.

Other Affiliation 【 Display / hide 】

Graduate school of Media and Governance, Committee Member

Career 【 Display / hide 】

1994.04

-

2004.02

Sony Corporation, CE Software Platform Division, Senior Software Project Manager
1999.09

-

2000.09

Georgia Institute of Technology, College of Computing, Research Scholar
2001.10

-

2003.12

NTT DoCoMo, Inc., Customer Equipment Development Department, Manager
2004.02

-

2011.03

Sony Ericsson Mobile Communications, Inc., Software, Tokyo Development / Tokyo Engineering, Director, Sony MVP2004
2010.07

-

2011.03

Sony Ericsson Mobile Communications (USA), Inc., R&D Group, Senior Project Manager

Academic Background 【 Display / hide 】

1988.04

-

1992.03

Keio University, Faculty of Science and Technology, Department of Electrical Engineering

University, Graduated
1992.04

-

1994.03

Keio University, The Graduate School of Science and Technology, Computer Science

Graduate School, Completed, Master's course
2021.04

-

2025.03

INSTITUTE of INFORMATION SECURITY, Graduate School

Graduate School, Completed, Doctoral course

Academic Degrees 【 Display / hide 】

Ph.D., INSTITUTE of INFORMATION SECURITY, Coursework, 2025.03

Sybil-Resistant Self-Sovereign Identity Based-on Attested Execution Secure Processors

Matters concerning Career Achievements 【 Display / hide 】

1994.04

-

Present

Practical experience in the consumer electronics and mobile industries

　View Details

He has 32 years of practical experience at Sony, Sony Ericsson, and NTT DOCOMO. During that time, he contributed to and achieved several world and domestic firsts. These include the real-world adoption of an object-oriented OS, the development and implementation of the world's first device software update system using a commercial mobile phone network, the development and implementation of smartphones, and the FIDO authentication and passkey project.

Research Areas 【 Display / hide 】

Informatics / Information security (Social deployment of digital infrastructure, digital identity and authentication, device architecture and mobile)

Research Keywords 【 Display / hide 】

Social deployment of digital infrastructure, digital identity and authentication, device architecture and mobile

Research Themes 【 Display / hide 】

Trust and security architecture for the digital age and its deployment strategy,

2026.04

-

Present
Cryptographic Approaches for Digital Identity Preserving Privacy,

2022.02

-

Present

Papers 【 Display / hide 】

Sybil-Resistant Self-Sovereign Identity Based-on Attested Execution Secure Processors

Koichi Moriyama

2025.03

Doctoral thesis, Single Work, Lead author, Last author, Corresponding author, Accepted
Sybil-Resistant Self-Sovereign Identity Utilizing Attested Execution Secure Processors and Zero-Knowledge Membership Proofs

Koichi Moriyama and Akira Otsuka

IEEE Access 13 17919 - 17944 2025.01

Research paper (scientific journal), Joint Work, Lead author, Last author, Corresponding author, Accepted

　View Summary

Increasing attention to digital identity and self-sovereign identity (SSI) is gaining momentum. SSI brings various benefits to natural persons, such as owning controls; conversely, digital identity systems in the real world require Sybil-resistance to comply with anti-money laundering (AML) and other needs. CanDID by Maram et al. proposed that decentralized digital identity systems may achieve Sybil-resistance and preserve privacy by utilizing multi-party computation (MPC), assuming a distributed committee of trusted nodes. Pass et al. proposed the formal abstraction of attested execution secure processors (AESPs) while equipping hardware-assisted security in mobile devices has become the norm. We first describe our proposal to utilize AESPs for building secure Sybil-resistant SSI systems, the architecture with a set of system protocols ΠGatt , which brings drastic flexibility and efficiency compared to existing systems. In addition, we propose a novel scheme that enables users (holders) to request verifiers to verify their credentials without AESPs, and it further achieves unlinkability among credentials created for public verification. Our scheme introduces a simplified format for computed claims and commitment-based anonymous identifiers. We also describe a technique to utilize zero-knowledge membership proofs, in particular, “One-Out-of-Many Proofs” Σ -protocol by Groth and Kohlweiss, which can prove the existence of an expected credential without identifying it. Along with other techniques, such as utilizing the BBS+ signature scheme, we demonstrate how our scheme can achieve its goals with the extended anonymous and Sybil-resistant SSI system protocols ΠGatt+ . Entitling unlinkability among derived credentials in the anonymous Sybil-resistant SSI results in proper privacy preservation.
- Access to Document (DOI)
Permissionless Blockchain-Based Sybil-Resistant Self-Sovereign Identity Utilizing Attested Execution Secure Processors

Koichi Moriyama and Akira Otsuka

IEICE Transactions on Information and Systems - Special Section on Blockchain and Security E107.D ( 9 ) 1112 - 1122 2024.09

Research paper (scientific journal), Lead author, Last author, Corresponding author, Accepted

　View Summary

This article describes the idea of utilizing Attested Execution Secure Processors (AESPs) that fit into building a secure Self-Sovereign Identity (SSI) system satisfying Sybil-resistance under permissionless blockchains. Today's circumstances requiring people to be more online have encouraged us to address digital identity preserving privacy. There is a momentum of research addressing SSI, and many researchers approach blockchain technology as a foundation. SSI brings natural persons various benefits such as owning controls; on the other side, digital identity systems in the real world require Sybil-resistance to comply with Anti-Money-Laundering (AML) and other needs. The main idea in our proposal is to utilize AESPs for three reasons: first is the use of attested execution capability along with tamper-resistance, which is a strong assumption; second is powerfulness and flexibility, allowing various open-source programs to be executed within a secure enclave, and the third is that equipping hardware-assisted security in mobile devices has become a norm. Rafael Pass et al.'s formal abstraction of AESPs and the ideal functionality Gatt enable us to formulate how hardware-assisted security works for secure digital identity systems preserving privacy under permissionless blockchains mathematically. Our proposal of the AESP-based SSI architecture and system protocols, ΠGatt, demonstrates the advantages of building a proper SSI system that satisfies the Sybil-resistant requirement. The protocols may eliminate the online distributed committee assumed in other research, such as CanDID, because of assuming AESPs; thus, ΠGatt allows not to rely on multi-party computation (MPC), bringing drastic flexibility and efficiency compared with the existing SSI systems.
- Access to Document (DOI)
Phishing-Resistant Multifactor FIDO (Fast Identity Online) Authentication

Koichi Moriyama and Keiko Itakura

日本セキュリティ・マネジメント学会誌 37 ( 2 ) 24 - 33 2023.12

Research paper (scientific journal), Lead author, Last author, Corresponding author

　View Summary

本稿では，FIDO（ファイド）アライアンスがW3C（World Wide Web Consortium）と共に推進するFIDO認証について解説する．近年，フィッシング攻撃などによる不正アクセスへの対策が急がれる中，FIDO認証はその対策の大きな決め手の一つとなる．FIDO認証は，リモートからの悪意者による攻撃を防ぐため，利用者による認証器の所持を基本とし，公開鍵暗号に基づく署名検証を利活用する．利用者にとって使い勝手が良く，フィッシング攻撃への耐性をもつ「シンプルで堅牢な」認証方式である．　FIDO認証は，2014年12月に公開されたFIDO 1.0仕様を皮切りに本格的な商用利用が開始され，現在はW3Cが策定するWeb認証（Web Authentication，WebAuthn）の勧告仕様を含めて総称するFIDO2が議論の中心となっている．そして，普及に向けて長い間課題となっていたいわゆるアカウントリカバリーについても一定の方向性が確立し，いま「パスキー」としてさらなる広がりが期待されている．その一方，FIDO認証のために必要な認証資格情報（クレデンシャル）を認証器から取り出すことを認めた結果，新たに取り組むべき課題も認識されつつあり，業界を挙げての取り組みが必要である． FIDOアライアンスは，FIDO2とパスキーに加えて，バイオメトリック部品認定，IoTデバイスと認証にまつわる課題を解決するFDO（FIDO Device Onboard）仕様なども展開し，パスワード課題の解決に向けてさまざまな観点から取り組んでいる．FIDO認証とWeb認証に対しては国内からの貢献も顕著で，引き続くグローバルとしての取り組みで，社会課題の解決に向けてさらに貢献できる．
- Access to Document (DOI)
Permissionless Blockchain-Based Sybil-Resistant Self-Sovereign Identity Utilizing Attested Execution Secure Processors

Koichi Moriyama and Akira Otsuka

情報セキュリティ総合科学 14 2023.02

Research paper (bulletin of university, research institution), Lead author, Last author, Corresponding author

Reviews, Commentaries, etc. 【 Display / hide 】

高まるセキュリティリスクへの対策について～お客さまを守るための『デジタルアイデンティティ』によるアプローチ～

電気通信 87 ( 931 ) 24 - 33 2024.08

Internal/External technical report, pre-print, etc., Single Work, Lead author, Last author, Corresponding author
FinTech Camp パスワード課題の解決に向けて（動画全6回）

森山　光一

FinTech Camp (日経BP) 2024.03

Article, review, commentary, editorial, etc. (other), Single Work, Lead author, Last author, Corresponding author

　View Summary

「　偽サイトで個人情報を盗み取るフィッシング詐欺の拡大などを受けて、パスワード不要の認証技術である「パスキー（Passkeys）」の導入が広がっている。米Appleや米Googleなどもパスキーを採用している。NTTドコモのチーフセキュリティアーキテクトで、パスキーの普及を進める標準化団体であるFIDOアライアンスの執行評議会・ボードメンバーでもある森山光一氏に、パスワードに内在する課題やパスキーの概要、最新状況を解説してもらった」（日経クロステック／日経FinTech 山端宏実）
FIDO認証とスマートフォンにおける生体認証技術

森山　光一

ISOパネル（第7回）：生体認証技術の金融サービスへの活用 ―新しい国際標準ISO 19092の概要と活用可能性― 2023.03

Lecture material (seminar, tutorial, course, lecture, etc.), Single Work, Lead author, Last author, Corresponding author
パスワードのいらない世界を実現する国際標準化活動を振り返って～TTC 会長表彰を受賞して～

森山　光一

TTCレポート 37 ( 4 ) 16 - 21 2023.01

Internal/External technical report, pre-print, etc., Single Work, Lead author, Last author, Corresponding author
マイナンバーカードの機能を利活用した民間IDの認証におけるセキュリティと使い勝手の高いレベルでの両立に向けて

森山　光一

総務省　第5回マイナンバーカードの機能のスマートフォン搭載等に関する検討会 2021.03

Meeting report, Single Work, Lead author, Last author, Corresponding author

Intellectual Property Rights, etc. 【 Display / hide 】

情報処理装置及びヒント提供方法

Date applied：特願2020-548197(P2020-548197), PCT/JP2019/033242 2019.08

Date published： WO2020/059428 2020.03

Patent, Joint
通信端末のソフトウェア更新方法、通信端末、及びソフトウェア更新システム

Date applied：特願2003-581005(P2003-581005) 2003.04

Date announced： WO2003/083647 2003.10

Patent, Joint
ダウンロードシステム、通信端末、サーバ、ダウンロード方法

Date applied：特願2002-348579(P2002-348579) 2002.11

Date announced：特開2004-185114(P2004-185114A) 2004.07

Patent, Joint
情報処理装置および方法、並びに記録媒体

Date applied：特願平１１－３４７０１９ 1999.12

Date announced：特開２００１－１６６９４１（Ｐ２００１－１６６９４１Ａ） 2001.06

Patent, Joint
データ処理方法、記録媒体及びデータ処理装置

Date applied：特願平１０－５２４９３ 1998.03

Date announced：特開平１１－２４９８９８ 1999.09

Patent, Single

Awards 【 Display / hide 】

2022年度情報通信技術賞 TTC会長表彰

2022.06, 一般社団法人情報通信技術委員会（TTC）, Ｗ３Ｃ及びＦＩＤＯにおけるパスワード課題を解決する認証に関する国際標準化及びその普及推進にかかわる功績

Type of Award： Award from publisher, newspaper, foundation, etc.
Sony MVP2004

2004.02, ソニー株式会社

Type of Award： Other

Other 【 Display / hide 】

Security Master, NTT

2022年04月

　View Details

In the NTT Group's security certification process, he was recognized for his outstanding skills and achievements and certified as a Security Master. (Renewed annually)

Courses Taught 【 Display / hide 】

Digital Identity and Deployment Strategy

2026, Spring Semester, Undergraduate (specialized), Lecture, Within own ｆaculty
研究会A

2026, Spring Semester, Within own ｆaculty
サイバーセキュリティ・ケーススタディ

2026, Autumn Semester, Postgraduate, Lecture, Within own ｆaculty
研究会A

2026, Autumn Semester, Within own ｆaculty

Courses Previously Taught 【 Display / hide 】

特別ゼミフィッシング詐欺対策とパスワードに代わる「パスキー」

HAL専門学校

2023.09

-

2025.09
,
Within own ｆaculty, 11h
NTT寄付講座サイバー攻撃対策技術の基礎（早稲田大学）

早稲田大学

2023.01
,
Postgraduate, Lecture, Within own ｆaculty, 2h

Media Coverage 【 Display / hide 】

脱パスワード技術「パスキー」、国内導入が倍増　証券口座乗っ取りで注目

日本経済新聞社, 日本経済新聞 (日経電子版、2025年12月6日朝刊 15面) , 2025.12
そのメール本物ですか？狙われる個人情報・カード番号

NHK, サタデーウオッチ９ (番組の後半、通信事業者としての取り組みとパスキーについて) , 2025.02
NTTドコモのチーフセキュリティアーキテクトが語る不正アクセス対策の鍵は「徹底的にお客さま目線」

Business Network, ＜サイバーセキュリティ戦記＞NTTグループのプロフェッショナルたち, 2024.03
NTT、サイバー人材に年3000万円も　実力主義で役員並み

日本経済新聞社, 日経電子版、日経産業新聞（NIKKEI BUSINESS DAILY） (1面) , 2023.07
The Key

The Asahi Shimbun Company, The Asahi Shimbun (The Asahi Shimbun Globe G2) , 2023.03

Memberships in Academic Societies 【 Display / hide 】

情報処理学会,

2026.04

-

Present
電子情報通信学会,

2023.10

-

Present
ACM (Association for Computing Machinery),

2022.04

-

Present
IEEE,

2022.04

-

Present

Committee Experiences 【 Display / hide 】

2025.09

-

2026.02

本人確認実務の課題・事例・手法とそのガイドラインに関する有識者会議構成員, デジタル庁
2025.08

-

2026.02

医療等分野における電子署名基盤のあり方検討会議構成員（有識者）, 厚生労働省
2024.07

-

2025.02

JIS X 0037 原案作成委員会, 日本産業標準調査会
2023.02

-

2023.08

重要情報を扱うシステムの要求条件検討委員会構成員, 経済産業省・IPA
2023.01

-

2025.03

本人確認ガイドラインの改定に向けた有識者会議構成員, デジタル庁