Research of cryptography with advanced functionality for e-book system

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K00188
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Information security
• Research Institution: Future University-Hakodate
• Principal Investigator: Shirase Masaaki 公立はこだて未来大学, システム情報科学部, 准教授 (70530757)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 暗号 / 楕円曲線暗号 / 高機能暗号

Outline of Final Research Achievements

In order to develop an e-book system that realizes copyright protection and lending and borrowing management that applies cryptography with advanced functionality, which has been actively researched in recent years, the research devised a lending and borrowing management system for e-books that does not require access to any server, and the system is experimentally confirmed the operation by mounting. Since pairing operation required for this method is a heavy process, an alternative to pairing operation is proposed, which is called Me operation, and the theoretical properties of Me operation are investigated. As a result, although encryption using Me operation is not yet put to practical use, it turned out that the attack is more difficult compared to the elliptic curve cryptosystem with the same key length.

Free Research Field

情報セキュリティ

Academic Significance and Societal Importance of the Research Achievements

2000年以降研究が盛んであるが実用化はあまり進んでいない高機能暗号を初めて電子書籍システムに応用した点が本研究の学術的意義である。本研究で用いた高機能暗号は再代理人暗号であるが、類似手法のIDベース暗号、属性ベース暗号、放送型暗号といった別の高機能暗号も電子書籍システムへ応用することで暗号技術により電子書籍システムに新たな機能の付加が可能であることを示唆しており、電子書籍システムの発展に寄与できる点が本研究の社会的意義である。