Research on Basic Information Security Technologies for Assured Conveyance of Users' Intention

我们处理了一个在数码信息环境下提高社会安全感的课题。特别是对保障用户意愿传递的基础信息安全技术的构建和评估进行了研究。我们的工作侧重于以下两点，旨在将“信息安全”作为“信息学”研究的一个分支。(1)安全意向传递和验证。目前，文件创建的意向是通过文件创建者签名或盖章以及接受者进行相应的验证等礼仪行为来表达的。我们希望在数字信息环境中为文件提供基本相同的保证。在这样环境中，存在作为人的用户、其包含软件和硬件的电子终端设备、以及位于网络环境中某处的第三方，以及用户…更多的人交流。我们研究了数字环境下上述组件中所需的安全机制。研究成果包括人机密码学、强制报警协议、防篡改软件技术、安全隐式询问、滞后数字签名、时间戳机制，以及利用生物特征人工测试对象对指纹、虹膜和静脉模式生物特征认证系统的安全评估方法。(2)技术环境变化的对策。许多信息技术的设计、实现和使用都是基于这样的假设：攻击需要巨大的计算量，硬件的抗篡改能力足够强。然而，这些假设取决于最新的技术水平。因此，我们需要一种长期安全的意向转移和验证方案，能够对技术环境的变化具有健壮性。我们在这一类中的结果包括信息理论安全密码方案的发展，密码算法及其实现的安全评估方法，人工产物度量系统和时间戳机制的安全评估方法。较少

We tackled a subject which enhances the social perception of security in a digital information environment. In particular, we conducted the research on the construction and the evaluation of basic information security technologies for assuring conveyance of users' intention. Our work set importance to the following two points aiming at developing "information security" as a wing of "informatics" studies.(1) Secure Intention Transfer and Verification.The intention to a document creation is currently expressed by ceremonial actions such as the signing or sealing by the document creator and by the corresponding verification by recipients. We would like to attain the substantially same level of assurance for documents in the digital information environment. In such environment, there exist users which are human being, their electronic terminal devices containing software and hardware, and the third parties located somewhere in the networked environment, and the counterparts to which the us … More ers communicate. We studied the desired sort of security mechanisms within the above mentioned components in the digital environment. Research results include the development of human-computer cryptography, duress-alarm protocols, tamper-resistant software technologies, secure implicit asking, hysteresis digital signatures, time-stamping mechanisms, and the security evaluation methodologies for fingerprint-, iris-, and vein-pattern biometric authentication systems by the use of biometric artificial test objects.(2) Countermeasure against Change of Technological Environment.A lot of information technologies are designed, implemented and used based on some assumptions such as that the immense amount of calculation is required for an attack, and one that the tamper-resistance of the hardware is strong enough. However such assumptions are dependant with the state of art. Thus we need long-term secure schemes for intention transfer and verification which can be robust against the change of technological environment. Our results in this category contains the development of information-theoretically secure cryptographic schemes, the security evaluation methods for cryptographic algorithms and their implementation, for artifact metric systems, and for time-stamping mechanisms. Less