Lightweight Blockchain for Authentication and Authorization in Resource-Constrained IoT Networks

The Internet of Things (IoT) expansion has exposed connected devices to significant security vulnerabilities, particularly in terms of authentication and authorization. Traditional solutions, such as centralized servers or Proof of Work (PoW)-based blockchain, are unfeasible due to the resource limitations of IoT devices, such as their low processing capacity and dependence on batteries. This study proposes a lightweight blockchain system based on a simplified Proof of Stake (PoS) consensus mechanism designed to optimize energy consumption and improve resilience to attacks in IoT networks. The system implements a hierarchical network topology that improves data propagation and transmission times, significantly reducing latency compared to distributed topologies. In addition, it uses lightweight cryptographic algorithms such as ECDSA for authentication and AES-128 for authorization, ensuring transaction security without compromising the efficiency of IoT devices. The results show that the system reduces energy consumption by 54% compared to PoW solutions in high-load scenarios while maintaining an average latency below 30 ms. Furthermore, the system achieved a 92.5% attack detection rate under low malicious load, demonstrating its effectiveness in high-threat environments. This work offers a scalable and efficient solution that optimizes security and performance in IoT networks, opening new possibilities for its application in critical infrastructures and real-time sensor networks.