CD-BASA: An Efficient Cross-Domain Batch Authentication Scheme Based on Blockchain With Accumulator for VANETs

Authentication plays an important role in verifying the integrity of messages and the identity of message senders in vehicular ad-hoc networks (VANET) applications. A significant challenge in expansive regions pertains to the efficient authentication of multiple vehicles traversing trust domains. This paper introduces a novel cross-domain batch authentication scheme for VANETs, denominated as CD-BASA, leveraging blockchain technology in conjunction with accumulator. The CD-BASA scheme is built upon blockchain with accumulator and interplanetary file systems for streamlined storage and batch computation. Subsequently, a proficient cross-domain batch authentication protocol for CD-BASA is devised, encompassing the establishment of domain-specific and global parameters, which greatly reduces the identity verification cost for multiple vehicles. To further minimize the overhead associated with batch validity proofing, a novel multi-accumulator batch proof algorithm is designed to greatly reduce the proof cost of multiple vehicle identities. Experimental evaluations and theoretical security analysis show that CD-BASA has better performance than other existing schemes, in terms of cross-domain batch authentication overhead (improving at least 18.2%) and accumulator proof overhead (reducing at least 69.9%).