Implementation of smart contracts for blockchain based IoT applications

An increasing number of people, organizations and corporations are expressing their interest in the decentralization technology of the blockchain. The creation of the blockchain marks the time when we start building distributed peer-to-peer networks consisting of non-trusting members that interact with each other without a trusted intermediary but in a verifiable manner. In this paper, we propose a decentralized application (DApp) based on blockchain technology for sharing Internet of Things (IoT) sensors' data, and demonstrate various challenges addressed during the development process. This application combines blockchain technology with IoT and operates through smart contracts that are executed on the Ethereum blockchain. More specifically the application is a platform for sharing (buying and selling) measurements of IoT weather sensors and operates on the Ethereum blockchain, acting as a marketplace for IoT sensor data. This application applies the Sensing-as-a-Service (S2aaS) business model combined with blockchain.