A Blockchain‐Based <scp>OBD</scp> Architecture for Secure Data Sharing in Smart Vehicle Ecosystems

ABSTRACT Intelligent Transportation Systems (ITS) are transforming urban mobility by enabling connected and smart vehicles. Despite advances, traditional ITS frameworks lack secure, real‐time mechanisms for directly sharing On‐Board Diagnostics (OBD) data between vehicles and owners. It exposes critical vehicle status information to risks of tampering, unauthorized access, and data inconsistency, undermining driver trust and system reliability. To address these challenges, this paper proposes a novel Blockchain‐based OBD architecture that securely records, manages, and shares vehicular diagnostic data in a decentralized and tamper‐resistant manner. Leveraging blockchain properties of immutability, cryptographic security, and consensus‐driven verification, our Vehicular‐to‐Owner (V2O) framework ensures data integrity and privacy while enabling owner‐controlled access for stakeholders such as mechanics, insurers, and regulatory bodies. The system mitigates vulnerabilities like Sybil and 51% attacks by integrating lightweight role‐based consensus, digital signatures, and a private‐permissioned blockchain platform. Experimental evaluation on real OBD datasets demonstrates promising results, achieving low latency (under 30 ms average transaction confirmation), sustaining throughput of more than 25 transactions per second, and efficient storage overhead, while reliably preventing unauthorized data access and tampering. These empirical results provide practical evidence supporting the feasibility of blockchain deployment in ITS contexts for secure V2O communication.