Improvement of security and efficiency of identity-based encryption schemes resilient to key leakage

2020 Fiscal Year Final Research Report

• Project/Area Number: 17K12697
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Information security
• Research Institution: The University of Electro-Communications (2017, 2019-2020); National Institute of Information and Communications Technology (2018)
• Principal Investigator: Watanabe Yohei 電気通信大学, 大学院情報理工学研究科, 助教 (40792263)
• Project Period (FY): 2017-04-01 – 2021-03-31
• Keywords: 暗号理論 / IDベース暗号 / 鍵漏洩耐性

Outline of Final Research Achievements

Identity-based encryption (IBE) is public-key encryption that enables us to use arbitrary strings, such as e-mail addresses, for public keys. In this project, we aimed to improve IBE schemes with various secret-key leakage resilience properties so that simultaneously achieve strong security levels and high efficiency, and to realize a new model of secret-key leakage resilience for IBE. We finally obtained various results on revocable IBE and key-insulated IBE, and formalized a new model of secret-key leakage resilience.

Free Research Field

暗号理論

Academic Significance and Societal Importance of the Research Achievements

通常のIBEにおいても高い安全性及び高い効率性を両立することは容易ではなく，近年やっと体系化されてきた研究指針である．しかし，機能付きIBEは通常のIBEとは枠組みから異なるため，IBEにおける指針がそのまま適用できる場合は少なく，学術的な工夫が必要であった．また情報漏洩インシデントは今もなお数多く起きており，そのような漏洩に耐性のある暗号技術の研究には社会的および学術的な意義があると考えられる．