AutoCrypt: Blockchain-Integrated Vehicle Access Control

Abstract

Traditional vehicle access systems rely on symmetric cryptographic mechanisms such as rolling codes, which are vulnerable to Relay and Replay attacks. This paper presents a secure vehicle access architecture integrating Elliptic Curve Cryptography with revocation mechanisms and blockchain-based audit. The proposed system uses ECDSA over the secp256k1 curve for asymmetric authentication and nonce-based challenge-response verification performed locally on an Electronic Control Unit. A blockchain layer is used for tamper-resistant key revocation and logging. Performance evaluation shows that the system maintains authentication latency under 300 milliseconds while significantly improving security over conventional systems.