Dual Fine-Grained Authentication Without Trusted Authority for Data Collection in TDT Systems

In transportation 5.0, digital twin (DT) is considered a promising paradigm to integrate physical entities into cyber physical systems by collecting massive data. However, the open collection process and key exposure issues bring critical security challenges. Furthermore, applying the existing authentication schemes to data collection in transportation DT (TDT) systems encounters three deficiencies: 1) forward security for collected data can only be achieved at a coarse-grained level; 2) one or more additional trusted authorities are introduced, causing the robustness of TDT systems to be downgraded; 3) dynamic attribute updating and revocability of physical entities are rarely considered. Therefore, we propose a dual fine-grained authentication scheme (DFAS) in this paper. Our DFAS can not only ensure data integrity and authenticity but also enable fine-grained access control, namely, only registered physical entities with authorized attributes can generate valid signatures. Meanwhile, DFAS provides the key puncturing for physical entities to guarantee fine-grained forward security without relying on any trusted authority. In addition, a non-interactive attribute updating and revocation of malicious entities are realized in DFAS. Finally, the security analysis indicates that DFAS can deal with various security challenges for data collection in TDT systems. The performance evaluation demonstrates that DFAS is efficient and practical.