| dc.description.abstract | How to ensure the stability of vehicle safety information transmission is an important issue. If the information can be properly disseminated and stored, the government and relevant units can use the recorded data to develop relevant security applications. However, there are many nodes in the in-vehicle network, the network topology is extremely dynamic, and the marking information transmitted by each node will cause a heavy burden on the storage space. As an emerging decentralized database storage technology, blockchain has the characteristics of being difficult to tamper with and decentralized management. It is suitable for saving safety-related information transmitted by vehicles, and can better cope with its dynamic topology environment. However, the blockchain also has scalability challenges. The unlimited growth feature will increase the demand for power consumption as the running time increases, making the vehicle unable to bear the cost of mining. Blockchain pruning is one of the solutions to the scalability of the blockchain, removing less important information in the block and making the blockchain more suitable for the vehicle environment.
This paper proposes a secure message dissemination mechanism based on selective blockchain pruning. Blockchain is considered one of the solutions to improve VAENTs architecture because of its non-tamper and decentralized characteristics. But low throughput and scalability of blockchain is a challenge, and the nodes in VAENTs can not handle a large amount of computing demand. The Proof of Authority (PoA) consensus mechanism sacrifices the decentralized nature of blockchain for centralized management in exchange for high throughput and scalability, which is more suitable for VANETs. Also, because there is no miner in PoA, it can avoid the problem of high carbon emissions during blockchain operations and ensure that it does not cause environmental issues. At the same time, design a reputation mechanism to mitigate the centralization situation and avoid malicious behavior to guarantee the average distribution of block generation rights. The proposed selective blockchain pruning mechanism selects the speed of the vehicle and accident information as references to determine whether the data recorded in the blockchain is important or not. The pruning mechanism can reduce storage space consumption while preserving important data.
The experimental results show that the blockchain designed in this paper has a faster block generation speed compared with Ropsten and Rinkeby, the Ethereum test network, which can reduce the block generation time by 59.96% and 64.01%, respectively. The reputation mechanism enables the average distribution of block generation rights, which differs from the estimated value by only 10.08%. In addition, the proposed pruning mechanism can reduce the storage space consumption by 68.01%. | en_US |