Noble Inheritance Mechanism of Digital Content for "Digital-Ji-in" toward Sustainable Society

Various research and development efforts have been made to implement cyber-physical systems, aiming to maintain the associations between digital and physical identities (such as sensors, events, or people). In this study, we consider a scenario with the inheritance of digital content owned by a deceased person. People increasingly store their information (such as digital photos and videos) in cloud services, and this content may become inaccessible to the relatives in case of an unexpected death. In this paper, we propose a method for realizing a noble inheritance mechanism for secret digital content in "Digital-Ji-in" which maintains digital identities toward sustainable society. Specifically, we use a secure secret scheme to realize the noble inheritance mechanism. The "shares" of the encryption key are distributed to future heirs and the trusted third party such as cloud provider. The cryptographic key cannot be recovered until all the heirs' shares are united and the trusted third party's shares are obtained. This paper describes and analyzes the proposed method. Moreover, it outlines a preliminary scenario with "the right to be forgotten." The proposed method can help maintain the connection between the real world and cyberspace in perpetuity.