Using Stellar Consensus Protocol to Ensure the Security of Message Transmission in VANETs

In a Vehicular Ad-Hoc Network (VANET), vehicles and Road Side Units (RSUs) communicate with each other to share real-time information about road conditions. This enables vehicles to avoid traffic jams and assists rescue efforts. Emergency messages can also be sent to request rescue during emergencies. However, malicious attackers can compromise driving safety by providing false or delayed information. For example, a driver may receive a message indicating clear traffic on a congested or accident-stricken road, resulting in further congestion and hindering rescue efforts if they do not detour. Ensuring the authenticity, timeliness, security, and liveness of transmitted messages is crucial for VANET safety. The Stellar Consensus Protocol (SCP) is built on the Federated Byzantine Agreement, which allows for the dynamic selection of nodes and quick consensus. SCP ensures the security and liveness of the consensus process, making it suitable for VANETs. In this study, vehicles and RSUs were regarded as nodes, allowing vehicles to select nearby vehicles as slices dynamically. Slices from other nodes can be added to form a quorum, and nodes can reach a consensus by transmitting messages between different phases. The final output value represents the group's confirmation of current road conditions. RSUs and vehicles were divided into different tiers based on different attributes, and the number of slices was adjusted to evaluate their performance, safety, and liveness. A vehicle reputation system was incorporated to improve the nomination process. The study also simulated common obstacles encountered during message transmission in VANET, and the results showed that SCP is viable in VANET and can ensure the security of message transmission.