公益財団法人 セコム科学技術振興財団
研究成果報告書

研究課題名

情報法学・マネジメント論と侵入防止技術の融合による超セキュア情報システム

Ultra-Secure Information Systems by Integrating Information Laws, Management
Methodologies and Invasion Prevention Technologies

研究期間
平成 25 年 4 月 ～ 平成 29 年 3 月

報告年月
平成 29 年 6 月
研究代表者
東京大学 情報理工学系研究科 電子情報学専攻 教授
坂井 修一
Professor
Department of Information and Communication Engineering,
Graduate School of Information Science and Technology,
The University of Tokyo
Shuichi Sakai
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Abstract
Along with the development of the information system as a social infrastructure, it is the pressing
need for us all to ensure information security. In recent years, zero-day attacks and targeted attacks
cause serious troubles such as leakage of important information and takeover of IT systems. Leakageof private information and invasion of privacy have become two of the most significant socialproblems. This research project aims to propose, design and verify innovative technologies, laws,policies and management systems in each field and to research and develop methods thatcomprehensively solve by the integration of the all fields.
The subject areas here are jurisprudence on information society, management systems, andinformation system engineering.
At the preparation stage, we conducted surveys in each field, concretely analyzed the mostimportant problems, investigated the requirements of policies and technologies, proposed andpreliminarily evaluated the basic ideas on both sides of the social science and the technology. Inaddition, we examined integration of the social science and the technology, and conducted casestudies on cyber attack prevention and personal information protection, respectively, and made aprospect for the outcome of this research as a whole.
[Juriprudence]
The Japanese information law is based on the concept of respecting universal value of individual,
the Personal Information Protection Commission takes a significant role in harmonization the rulesof privacy and personal data protection with the ＥＵ and the United States. The Commission
aimed to establish a system of executive cooperation with other countries, and have proposed arevision for such while maintaining to consider Japan’s personal information protection legislation.
Meanwhile, in the background, the declining of the birth-rate and the elderly population in Japan
has made the maintenance of the social security system getting structurally difficult. As individual
burden increases day by day, the survival rights of individual are being threatened.
In order to maintain the social security system, increasing tax revenues through economic growthand securing financial resources are major issues. The “Big Data Business” is consider as one of theinformation technology (IT) industries that can contribute to such the growth. As such to promote
the IT industry, innovation through research and development is required. It is a prerequisite toestablish a legal system that secures freedom of academic and research, and to develop a legal
framework to ensure distribution of information across the border as well as domestically. Theseprerequisites are reflected in the revised draft of the Personal Information Protection law.
[Management System]
In order to develop more effective information security management system, we took firstly aliterature survey mainly focusing on the ISMS standards which has been rapidly developed since2

around 2000. At the same time, we also made an investigation of actual practices by making
enquires and interviews upon large sized commercial companies in Japan. Based on thesepreliminary surveys, underlying requirements, problems and our research focus for information
security management are identified.
In addition, we examined international Enterprise Architecture standards and their consideration
in information security to apply its intrinsic holism characteristic of EA as we thought the study ofEA would enrich our research.
A mathematical risk analysis method and tangible governance process were developed as a resultof these considerations, since we understood that the two prevalent key problems in this field arelack of objective risk analyses and malfunctions of senior officers' roles in information security
management. Existing information security standards, related researches, actual information
security system and incidents in Japan and U.S. government are also reviewed to verify ourdiscussion.
On the ground of the above, we proposed a novel systemic approach of information security
governance. Our result fills the gap which resides among existing standards, researches andpractices. It clarifies the importance of information security to business, and provides a mean tocomplement the weaknesses of technology based security solutions. Although we also surveyed thesituation of the latest security measures such as the Cyber Security Directive of the U.S. Obama
Administration, it is almost omitted from our reports; their focus is put on critical infrastructure
protection and information sharing for its purpose.
Our proposed approach of information security governance is applicable to information security
management system in governments implemented under, for example, FISMA(Federal Information
Security Modernization Act) or another similar information security management concepts like inJapan.
[Technology]
In security technology (especially intrusion prevention technology in this case), we analyzed casesof intrusions and information leaks from the past to the nearest, and also collected observation dataof computer abnormal states. Based on these, we established the principles of an intrusion detection
system and information leakage prevention platform, and specifically examined detection methods
and countermeasures in case of intrusion. In order to comprehensively prevent data leakage andtampering, we focused on the following three subjects and conducted research.
The first is security assurance in the case where the system administrator and the right holder ofthe data are different. Protection from tampering of client information by a cloud provider and fromillegal duplication of DRM contents by a user system are two of the examples. In this research,focusing on secure processor technology to solve such problems, we have developed the mechanismand organization of the VM secure processor "Sharkcage" based on the recent VM technology. By
using the processor as the base of trust in the core of the computer system, it is proved possible to3

guarantee that the intention of the legitimate right holder is properly reflected in processing. It
realizes platform validity authentication and confidentiality / integrity of external data byappropriate cryptographic technology, and reduces the overhead of cryptographic processing byarchitectural technology to achieve both efficiency and security.
The second is to prevent from an intrusion exploiting carelessness of administrators andprogrammers. Virus infection and data alteration due to vulnerability, data stealing by the phishingsite, system takeover by Trojan horses, Ransomware, etc. are getting fiecer and fiecer. The basic
countermeasure technique was to record bit patterns and behavior patterns of the attack signals tocreate a database and quarantine attacks at the water's edge. However, it is currently quite difficult
to cope with highly intentional and dangerous attacks, such as zero-day attacks and targetted
attacks. In this research, we develop "information flow tracking technology" and realize a systemthat the computer constantly inspects the computer itself whether the operation the computer isabout to do is intended by the rightful right holder, and detects the attack.
The third is to protect against social hacks exploiting how people use IT systems. Even if security
measures are correctly taken on the system, intrusions from the interface of physical world / virtualworld have been rapidly increasing, exploiting people’s way of using IT devices such as passwords
carelessly written down or easily guessable by IoT sensors, and of carelessly using a malicious
wireless router pretending to be legitimate. It is expected that these kinds of attacks will become
more and more universal and advanced as the information platform gets smaller and more wireless.
In this research, we developed a human computer interaction (HCI) technology that allows users to
log in and connect to IoT devices and computer systems intuitively for users. Based on user's location
information and gestures, it can connect securely without making a password to wireless routers, IoT
devices, household appliances, etc.
[Integration]
As for the integration of research fields, we examined what juriprudence, management, andtechnologies should do for zero-day attacks, targetted attacks, personal information leakage andcopyright infringement, based on the latest results of each field and each new role sharing, andcooperation.

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