Efficient Consensus and Elastic Resource Allocation Empowered Blockchain for Vehicular Networks

Abstract

With the advantages of decentralization and high reliability, the blockchain is widely used in vehicular networks, which has attracted widespread attention from academia and industries. However, when combining blockchain into vehicular networks, there exist three challenges: 1) how to access pre-deployed blockchain when vehicles are disconnected from network infrastructures, 2) how to reduce the communication overhead caused by an increasing network scale while maintaining decentralization of blockchains, 3) how to balance limited vehicle's resources and high throughput of blockchain. To address these challenges, we propose an efficient Device-to-Device (D2D) Network-empowered blockchain framework to receive and process transactions from D2D vehicles. We then propose a grouped and leaderless consensus mechanism to reduce communication overhead as the network scale increases. We also propose an elastic resource allocation scheme using the Lyapunov optimization theory to achieve high throughput given limited resources. Finally, numerical results show that the proposed mechanisms achieve D2D interaction under different network conditions and better performance than existing approaches.