부산대학교 도서관

We propose a secure and lightweight continuous authentication scheme for IoT devices as an alternative to key-based authentication based on physical channels. Existing physical-channel-based authentication methods have limitations such as poor robustness, high reconciliation overhead, and a lack of secrecy for authentication keys. Our proposed authentication scheme utilizes the IoT devices' grant-free non-orthogonal multiple access transmission model for seed generation and authentication, providing continuous authentication by examining access time slots and spreading sequences. Thus, the proposed authentication scheme eliminates the need for coherent keys, thereby concealing seed information from attackers. Our scheme outperforms benchmark schemes, showing reduced misdetection of illegitimate devices and near-zero false alarms. It also has significantly lower computational complexity compared to other benchmark schemes. These results confirm the practicality and effectiveness of our proposed authentication scheme for IoT devices.