A Blockchain-Enabled Framework for Privacy Preserving Smart Mobility Services

Smart mobility services generate large volumes of sensitive location and identity data, raising critical concerns related to privacy leakage, ‎security vulnerabilities, and trust in large-scale urban deployments. To address these challenges, this paper proposes a blockchain-based ‎privacy-preserving framework for smart mobility services that integrates geo-indistinguishability, pseudonymous authentication, Zero-‎Knowledge Proofs (ZKPs), and Proof-of-Authority (PoA) consensus into a unified architecture. The framework ensures end-to-end privacy ‎by combining calibrated location obfuscation with decentralized transaction validation and immutable auditability, thereby mitigating both ‎inference-based attacks and reliance on centralized trust.‎ The proposed framework was evaluated using the TAPAS Cologne mobility dataset, comprising 1,000 simulated vehicles and 20 block-‎chain validators. Experimental results demonstrate that adversarial inference accuracy is reduced to below 12%, while approximately 75% ‎navigation utility is preserved at balanced privacy budgets. Security analysis confirms robust protection against tracking, replay, Sybil, and ‎collusion attacks, with replay attack success rates reduced from 70% to 2% through the enforcement of timestamps and nonces, along with ‎cryptographic verification.‎ Performance evaluation demonstrates that the framework achieves high throughput (1,200 transactions per second) with sub-second latency ‎‎(0.8 seconds) under realistic transaction loads. Storage growth is optimized to 2.1 GB per million transactions, and the PoA consensus ‎mechanism achieves approximately 30% lower energy consumption compared to Proof-of-Stake-based designs. In addition, resilience ex-‎periments confirm Byzantine fault tolerance under up to 30% malicious validator participation, without service degradation.‎ Overall, the results demonstrate the practical feasibility of deploying the proposed framework in real-world smart mobility ecosystems that ‎require simultaneous privacy preservation, scalability, and energy efficiency. The framework represents a significant step toward trustwor-‎thy, privacy-aware, and sustainable smart-city mobility infrastructure, providing a robust foundation for next-generation decentralized mo-‎bility services‎.