## 3 Auto-Insurance Systems Based on Cloud or Blockchain
### Hybrid Auto-Insurance  
As discussed in the previous sections, cloud- and blockchain-based solutions have been proposed for the insurance sector to solve the problems of the existing manual systems. However, blockchain and cloud computing have their own advantages and disadvantages; thus, when combined, they could overcome each other's shortcomings and provide a better solution. A blockchain-based solution for vehicular forensics was introduced in [49], which integrated the involved entities and facilitated the provision of the data needed to settle disputes. This framework was used to collect vehicle data from drivers, maintenance centers, manufacturers, and other agencies and then upload them onto the cloud. Blockchain was adopted to monitor vehicle-related data, including maintenance information and vehicle diagnostics reports. The authors utilized driving data from the on-board diagnostics (OBD) port and EDR to provide valuable complementary evidence to resolve traffic accidents and disputes among parties. The solution proposed in [49] stored data in the cloud without considering data privacy. In this regard, the authors of [50] investigated and examined the numerous elements needed to protect privacy, as well as the privacy problems faced by CAVs. [PERSON] et al. [50] proposed a hybrid cloud- and blockchain-based model in which the cloud was used to store data and the blockchain helped to secure data exchange due to its reliability and trustworthiness. In this approach, a consensus algorithm called proof of driving was used to authenticate the car within the network. The framework improved the privacy and secrecy of communication between vehicles by offering a rapid and safe infrastructure. All authenticated transactions were summarized in a Merkle tree, which was produced by repeatedly hashing the data and producing new Merkle roots. For each specified time slot, a hash value was assigned to each string collected in a local database. The Merkle tree was updated, and this hash value was added as a leaf node, resulting in the creation of a new block in the blockchain. This approach led to an intelligent data transmission system based on blockchain technology, smart connected vehicles, and vehicular cloud computing. Although vehicle automation helps in many ways, such as by establishing a faster and more accurate means of information storage and transmission, the dissemination of fake information cannot be ignored. The issue of security problems in smart cars was examined by [PERSON] et al. [51]. A permissioned blockchain-based reputation system was employed to prevent the dissemination of false information throughout the network. The authors introduced the B-FERL protocol, which monitored each vehicle's internal state and looked for instances of vehicle compromise. This system used a challenge-response data-exchange mechanism between RSUs and vehicles to keep track of the vehicles' internal health and spot any malicious activity in the network. Furthermore, only the previous and current transactions of each vehicle were stored in the network node to ensure scalability and forward other transactions to the cloud so that the previous record could be accessed when required. Health insurance is also an emerging field. A basic design for a cloud- and blockchain-based health insurance system was proposed in [52] using sequence diagrams, a data management framework, a smart notification system, and a smart claims processing system. This work suggested a blockchain-based alternative to improve the National Health Insurance System (NHIS) in terms of financial sustainability in Ghana. The authors emphasized the significance of information quality, service quality, and user satisfaction as essential components in the adoption of an effective cloud- and blockchain-based solution. In this research, the authors discovered a significant relationship between user satisfaction and information quality.