DIMA: A Post-Quantum and Privacy-Preserving Decentralized Identity Management Architecture for Secure V2X Authentication

Abstract

The security and privacy of vehicle-to-everything (V2X) communication are critical for the reliability of future intelligent transportation systems (ITS). Existing V2X public key infrastructure (VPKI) models face centralization risks, inefficient revocation, limited privacy, and vulnerability to quantum attacks. While blockchain-based frameworks improve decentralization, they often depend on classical cryptography and offer limited defense against Sybil attacks and identity linkage. This paper presents DIMA, a post-quantum decentralized identity management architecture for V2X authentication and privacy preservation. DIMA integrates a dual-layer permissioned blockchain with CRYSTALS-Dilithium for quantum-resistant digital signatures, zk-STARKs for anonymous pseudonym issuance, and privacy tokens with a reputation-based refresh mechanism for Sybil resistance. A hash-based accumulator supports scalable revocation, while self-sovereign identity (SSI) and zero-knowledge attribute proofs enable privacy-preserving access control. Security is analyzed under a quantum-capable adversarial model, and performance is evaluated using analytical benchmarks. Results demonstrate that DIMA achieves strong unlinkability, scalable Sybil deterrence, and real-time authentication, addressing key limitations of prior approaches and providing a quantum-resilient foundation for next-generation V2X ecosystems.