# A Blockchain Solution for the Internet of Vehicles with Better Filtering and Adaptive Capabilities
## 5 IoV System Model Based on AE-PBFT Algorithm
### Possible Attacks  
The IoV system faces a variety of malicious threats in real-world operating environments. Compared to external attacks, internal threats are more challenging to detect and prevent, as they often originate from within the system and exploit its trust-based architecture. Attackers can undermine network stability and disrupt the trust foundation of IoV through various means, compromising the safety and efficiency of vehicular communication and decision-making. Below, we outline and analyze four common types of attacks in IoV environment:  
(1) Direct attacks from malicious vehicles: Malicious vehicles can directly send false or misleading messages to nearby vehicles. These false messages may include incorrect information about traffic conditions, road hazards, or vehicle positions, leading surrounding vehicles to make inappropriate or dangerous decisions. For example, a malicious vehicle could falsely broadcast the presence of a traffic jam or an accident ahead, causing other vehicles to reroute unnecessarily, leading to congestion on alternate paths. Alternatively, it could send incorrect positioning data, resulting in collisions or traffic disruptions. Such attacks exploit the decentralized nature of IoV, where vehicles rely heavily on real-time data from peers to make autonomous driving decisions. Detecting these attacks can be challenging, as the malicious messages may appear legitimate, and their impact can propagate quickly through the network;  
(2) Indirect attacks from malicious vehicles: In this type of attack, malicious vehicles do not directly interfere with other vehicles but instead target the reputation and trustworthiness of normal vehicles. They achieve this by sending false evaluations of legitimate vehicles to RSU, which is responsible for maintaining trust records and calculating credibility scores. By distorting the credibility judgments of normal vehicles, attackers can manipulate the system to distrust reliable vehicles, thereby disrupting the normal operation of IoV. For instance, a malicious vehicle may report that a well-behaved vehicle has been sending incorrect data or behaving erratically. This can lead to the legitimate vehicle being excluded from consensus processes or other cooperative tasks within the network. Over time, such manipulation can erode the reliability of IoV's trust mechanisms and lead to cascading system failures;  
(3) Direct attack on RSU: As a critical component of IoV, the RSU serves as a local hub for communication, data storage, and trust management. Direct attacks on an RSU involve an attacker infiltrating the unit, either physically or through network vulnerabilities, to manipulate its stored data. This may include altering historical credibility evaluations, tampering with trust scores, or modifying vehicle-related data. For example, an attacker could modify the stored trust score of a malicious vehicle to make it appear trustworthy, allowing it to participate in consensus or mislead other vehicles. Similarly, the attacker could delete or modify records of legitimate vehicles, undermining their credibility and potentially excluding them from the network. Such attacks can have a widespread impact, as the RSU often serves multiple vehicles within its communication range, and compromised data can propagate through the network;  
(4) Indirect attack on RSU: Unlike direct attacks, indirect attacks on the RSU target its internal logic rather than its stored data. In an indirect attack, the attacker modifies the algorithms or parameters used by the RSU to calculate vehicle credibility. For example, the attacker could alter the weighting of specific trust metrics or introduce biased parameters that favor malicious vehicles. This manipulation could render the RSU incapable of accurately evaluating the trustworthiness of vehicles, allowing malicious nodes to evade detection while penalizing legitimate vehicles. Such attacks are particularly dangerous because they undermine the foundational processes that maintain trust in IoV.