## 8 Blockchain in Autonomous Vehicles
### Blockchain Potential Risks in AVs  
Blockchain technology, heralded as a game changer for numerous industries, also shows promise in transforming the realm of autonomous vehicles (AVs). However, it is imperative to carefully navigate the intricate web of challenges and risks associated with its implementation:  
* Scaling bottlenecks: Major blockchain networks such as Ethereum and Bitcoin exhibit constrained processing capacities, hovering around 5 to 20 transactions per second [133]. When juxtaposed with the high-velocity data exchanges integral to vehicular networks, these limitations pose significant challenges. It is imperative to develop or adopt blockchain architectures that are nimble enough to accommodate the velocity and volume of data inherent in autonomous vehicular systems. * Cyber security threats: The complex communication networks that form the backbone of AV interactions are not impervious to cyber threats. These networks could be prey to attacks that not only compromise data but also imperil human lives through accidents instigated by erroneous or manipulated data [133]. To address this, cyber security mechanisms need to be woven into the blockchain fabric to fortify the system against intrusions and hacks. * Navigating privacy concerns: Although blockchain technology's decentralized ledger systems improve security, the irreversible nature of data that is held on blockchains may pose privacy problems if not managed properly. It is essential to make use of privacy-enhancing technology, either via zero-knowledge proofs or other cryptographic approaches, in order to bring blockchain's transparency into harmony with the need for user anonymity and data security. * Integration complexities: The rapid rate of innovation in hardware and software stands in stark contrast to the longer service life cycles of vehicles [134]. The integration of blockchain into the dynamic ecosystem of autonomous vehicles demands an agile approach, possibly through modular and adaptable frameworks that can keep pace with technological advancements without necessitating wholesale infrastructural changes. * Environmental and resource stewardship: Certain blockchain frameworks, particularly those reliant on proof-of-work consensus algorithms, are notorious for their prodigious energy consumption. Beyond the environmental repercussions, the resource intensiveness of these systems could also tax the computing capacities within vehicles. Alternative consensus algorithms such as proof of stake or proof of authority might mitigate these challenges, striking a balance between security and resource efficiency. It is crucially important to adopt an intelligent and forward-thinking strategy in order to maximize the revolutionary potential of blockchain technology in autonomous cars and enjoy the benefits of this potential. This requires the development and implementation of blockchain frameworks that are scalable, secure, and resource-efficient, along with the integration of privacy protections and cyber security defenses. The academic literature emphasizes both the exciting prospects, as well as the inherently difficult obstacles, that are associated with the combination of blockchain technology and autonomous cars. The potential security flaws that are associated with connected autonomous vehicles (CAVs) were investigated in depth in critical research that was carried out by [PERSON] et al. [135]. The study focused on the potential solutions that may be provided by blockchain technology. Notably, the study highlighted the potential of blockchain technology to improve the reliability and integrity of data transfers, as well as intervehicle communication. In a study that echoes similar results, [PERSON] et al. [136] conducted an in-depth investigation of the threat scenario posed by CAVs and highlighted the potentially game-changing role that blockchain technology may play in the fortification of vehicle networks.