LIGHTWEIGHT DAG-BLOCKCHAIN FRAMEWORK FOR TRUST MANAGEMENT IN EDGE-ASSISTED VANETS

Abstract

Highly dynamic topology and unreliable vehicular behaviors remain major chal- lenges for blockchain-enabled trust management in Vehicular Ad Hoc Networks (VANETs). Conventional blockchain schemes often suffer from excessive consen- sus latency, communication overhead, and limited scalability in dense vehicular environments. To address these limitations, this paper proposes a lightweight DAG-blockchain framework for trust management in edge-assisted VANETs. The proposed framework integrates mobility-aware trust inference, asynchronous DAG validation, and edge-assisted partial trust synchronization to improve trust reliability and communication efficiency. In particular, the trust model jointly considers communication reliability, forwarding behavior, relative mobility, con- tact duration, and topology stability for dynamic trust evaluation. Moreover, the DAG-based validation mechanism enables parallel transaction verification, reducing consensus delay compared with conventional chain-based blockchain architectures. Simulation results show that the proposed framework achieves approximately 93.7% trust accuracy and 94.5% malicious vehicle detection rate under dense VANET scenarios while reducing communication latency and signal- ing overhead compared with PBFT-based blockchain and conventional reputation- based trust schemes. Keywords: VANET; DAG blockchain; trust management; edge-assisted net- works; mobility-aware trust.