# Aspects of Cyber Security in Autonomous and Connected Vehicles
## 2 Related Work  
The authors in [16], surveyed attacks and defenses for connected and autonomous vehicles (CAV). Attacks on CAV are classified into three regions: in-vehicle network attacks, vehicle-to-everything (V2X) attacks, and other attacks. We provide defense strategies and necessary actions to overcome the attacks. Authors in [17], explained the basic concept of in-vehicle networks. The vulnerabilities and attacks on the in-vehicle networks and countermeasures to overcome them are provided. Authors in [18], provided a clear review of cyber-attacks on the sensing layers. The sensing layer is classified into two categories: vehicle dynamics sensors and environmental sensors. Vehicle dynamics sensors include magnetic encoders, inertial sensors, etc. Environmental sensors include cameras, lidars, radars, etc. Countermeasures for the two types of sensor attacks are provided. The authors in [19] have surveyed autonomous vehicles. We classified the possible attacks into five categories, vehicular ad hoc networks (VANETs) based on sensors, hardware attacks, adversarial attacks, and malicious attacks. Authors in [20], provided a clear review of the possible attacks on the connected vehicle. Based on the attacks, provided defenses were classified into four types of network security, software vulnerability detection, cryptography, and malware detection, and mentioned future possible defenses.  
The authors have surveyed attacks and defenses on vehicles from 2008 to 2019 based on analysis attacks are classified into an autonomous driving system, autonomous control systems components, and V2X communications [21]. Defenses for those attacks are classified into security architecture, intrusion detection, and anomaly detection. In the end, they discussed the artificial intelligence integration in autonomous and connected vehicles relates to smart cities. The authors in [22], focused on connectivity including V2X and in-vehicle communication and considered communication technology implementation as one of the major reasons for the cyber-attacks on these systems. They discussed the major cyber-attacks on intelligent connected vehicles and available defenses. They categorized the defenses into four likely cryptographies, network security, software vulnerability detection, and malware detection. They discussed future directions to avoid attacks on intelligent connected vehicles. A discussion on the attacks and defenses of the connected vehicle considers V2X as a major concern and challenge in state-of-the-art intra-inter vehicle communication which is well explored in [23]. The authors have discussed defenses that can avoid these attacks and understand the hacker's methods or way of attacking. Authors in [24], discussed the safety failures and cyber-attacks on the autonomous vehicle and collected possible countermeasures to take care of the safety and security of the autonomous vehicle.  
Existing works worked on attacks and defenses on one region such as a connected vehicle, autonomous vehicle, etc. This article is a review of possible attacks and defenses on a autonomous and connected vehicle. Attack regions for a autonomous and connected vehicle are classified into three categories safety systems, connectivity, and diagnostics. Safety systems include active safety systems and passive safety systems, connectivity is further classified into three regions V2X, in-vehicle, smart features, and diagnostics are classified as OBD ports and firmware over the air (FOTA). High possible attacks on these three classifications are explained and defenses for the attacks are mentioned. Future recommendations are provided to work on new defense strategies to overcome attacks.