# Improving IoT Data Security and Integrity Using Lightweight Blockchain Dynamic Table
## 4 Literature Review
However, the solution did not show the effects of using the chaos key on the security of the AES encryption and the efficiency of the security system against well-known IoT attacks. Furthermore, the new security system had been only compared with standard AES. In 2019, [PERSON] et al. [42] presented a lightweight scalable blockchain security and privacy system for IoT called LSB. The proposed solution addressed the impact of computation of blockchain technology and the limitation of scalability, which overheads and delays the performance of IoT devices. The proposed solution optimized the blockchain to work with low-resource IoT devices. The LSB achieves the high-resource devices which are joined to the IoT network to manage the public blockchain and ensures the end-to-end security and privacy of the network. Furthermore, the solution optimized the performance by using lightweight consensus and the extensive simulations results show that LSB improves the performance of the IoT network and minimizes the packet overhead. However, the proposed solution did not use real blockchain technology management on the IoT devices, and most of the processing depended on the high-performance devices in the network. In 2020, [PERSON], [PERSON], [PERSON] et al. [43] proposed a new three-dimensional blockchain architecture with a novel data structure to deal with heterogeneity and stability of IoT network and called it SpaceChain. The three-dimensional greasy heaviest-observed sub-tree (3D-GHOST) consensus mechanism was used for Spacechain to handle the issue of the network performance of IoT. The security mechanism is divided into two procedures: dynamic weight distribution and ready traversal. Moreover, the chain of the blocks is divided into two types: main chain and side chain. The solution with this dividing technique will only accept the first occurrence of a block after sorting the local ledger. The solution has been tested extensively to verify its performance and its security of the new solution. In 2021, [PERSON] et al. [44] introduced a multi-layer blockchain-based security model of IoT. The proposed solution was designed to simplify blockchain implementation to protect the IoT network. The k-unknown clusters were used to facilitate the multi-layer concept besides the hybrid evolutionary computation algorithm. The simulated annealing and genetic algorithm were used in the clusters to protect the private blockchaincommunication which occurred between the cluster heads and relevant base stations. The authentication mechanism and security had been enhanced with the blockchain approach when they were adopted by base stations and enabled secure communication among them. The comparison between the traditional blockchain and the proposed lightweight blockchain shows a better balance in the network latency and throughput. However, the multi-layer solution with many heavy algorithms has not been analyzed in terms of power consumption, as using such an algorithm will overhead the IoT devices' performance. In 2022, [PERSON] et al. [45] looked at the interaction between blockchain technology and AI, a singular force behind the development of intelligent and sustainable IoT applications. They mainly talked about how blockchain technology has advantages that might help the growth and development of sustainable IoT applications. They established a clever and sustainable conceptual framework that processes and gathers essential data using cloud computing, IoT devices, and artificial intelligence. To support multiple applications, the system offers digital analytics and stores outcomes in decentralized cloud repositories. A sustainable incentive structure is also made possible by the layer-based design, which may help safe and protected smart city applications. However, the proposed solution has not been examined in terms of power consumption, as using an AI algorithm requires extensive computational power. In 2022, [PERSON] et al.