The blockchain is nothing but a skilled magician one after one it is providing the mankind with wonders in the era of information technology and financial industry. In recent years, blockchain has received tremendous attention to providing a distributed, definitive, and auditable application in the Internet of Things (IoT). Most Internet of Things (IoT) is moving towards momentous scalability and security challenges. Blockchain technology is extravagant and entangles high bandwidth, prolongation, and memory overhead that are not compatible with IoT devices. This paper brings forward a new definitive, intimate, and lightweight masonry for IoT-based blockchain technology which forsakes the memory overhead and centralized system, while security and privacy benefits are maintaining. The preliminary investigation method is discussed a standardized IoT infrastructure, where data are stored and access is managed by a decentralized blockchain technology. The following integration method used terminal devices as network technology and Ethereum as the blockchain platform that produced backend that ensures high availability, security, and privacy, while replacing traditional backend systems. Diametrically, we illustrate the simulation outcome to highlight our approach that significantly related to security and privacy of Blockchain-based IoT applications.