International Research Journal of Education and Technology

The Internet of Things (IoT) has significantly transformed modern computing by enabling large numbers of interconnected devices to sense, process, and exchange data autonomously. Despite its rapid adoption, IoT ecosystems face persistent challenges related to data security, privacy, scalability, and reliability due to the limited computational, storage, and energy capabilities of IoT devices. Traditional centralized architectures introduce single points of failure and are vulnerable to cyberattacks, making them unsuitable for large-scale and mission-critical applications. Blockchain technology, characterized by decentralization, immutability, and cryptographic security, offers a promising solution to address these limitations. This paper presents a comprehensive blockchain architecture tailored for lightweight IoT networks. The proposed framework incorporates energy-efficient consensus mechanisms, hybrid on-chain and off-chain data storage, and lightweight cryptographic techniques to ensure secure, scalable, and efficient data management. Performance analysis and a smart city traffic management use case demonstrate the feasibility and effectiveness of the proposed architecture.

Index Terms— Blockchain, Internet of Things, lightweight networks, decentralized systems, smart contracts, data security.