Analysis of Blockchain Solutions for IoT: A Systematic Literature Review

The Internet of Things (IoT) aims at connecting things to the Internet in a peer-to-peer paradigm for data collecting and data sharing in our daily life. A blockchain is an immutable append-only ledger maintained by a peer-to-peer network, where the whole network needs to reach a consensus on the transactional data stored on the ledger. With the decentralization nature, the design of IoT and blockchain aligns with each other well. Blockchain has been integrated with the IoT to solve the existing IoT problems. Our research focuses on analyzing the solutions proposed in academia and the methodologies used to integrate blockchain with the IoT. Through conducting a systematic literature review (SLR) on peer-reviewed, published articles on blockchain-based solutions for IoT, we gather the knowledge on current technical approaches implemented to integrate blockchain into the IoT. Majority of the research in this space is either at a conceptual level or at a very early stage. However, we only found 35 published papers with the real implementation of blockchain in the IoT platforms. We elicit the challenges of the IoT that were being addressed, and the detailed design of the blockchain-based solutions from two perspectives, namely data management and thing management. The evaluation methods and metrics used by those works are also being recorded and analyzed. In addition to the analysis of the literature, we provide our insights on improving the existing solutions and research methodology based on our expertise and experience on the blockchain.