Implementation and Trust Evaluation of an Identity Verification System Using (Japanese) Individual Number Cards for an ID Re-binding Service

Sayako Shimizu, Hiroyuki Sato, Motonori Nakamura, Hikofumi Suzuki, Yasuo Okabe

Abstract: This study addresses the challenge of identity management for researchers who change their institutional affiliations, aiming to enable efficient and continuous use of research data across educational and research organizations. Although many organizations are developing their own research data management systems, researchers often lose access to previously available datasets when they move to new institutions. To tackle this issue, we propose a cross-organizational identity proofing system that maintains the assurance levels of IAL2/AAL2 (as defined by NIST SP 800-63) and completes the ID transfer entirely online. The core idea is to link pre- and post-move IDs by verifying the user's identity with researcher ID numbers, ORCID, and government-issued credentials. Specifically, we employ the Japanese Individual Number Card (commonly known as the “My Number Card”) to achieve robust identity verification, allowing seamless ID linkage among Identity Providers with high assurance levels. The system is implemented in the Orthros development environment—an ID linkage service provided by the National Institute of Informatics (NII)—using xID Co.'s API for Individual Card integration. Our approach is expected to mitigate ID management issues arising from researcher transfers and to enhance the efficiency of research data utilization across organizations.