A Blockchain-Integrated Cryptographic Protocol for Secure IoT Data Exchange

The growing Internet of Things (IoT), characterized by heterogeneous devices and vast data collection, faces critical security threats due to constrained computational resources, the lack of unified trust, and vulnerable traditional architectures. To address this, this paper proposes a novel Blockchain-Integrated Cryptographic Protocol that ensures confidentiality, integrity, authentication, and non-repudiation in data exchange by combining the efficiency of lightweight cryptography (Ascon AEAD) with the decentralization of blockchain-based identity and trust management using Elliptic Curve Cryptography (ECC) and smart contracts. A crucial gateway-assisted blockchain mechanism is introduced to offload computational burden from constrained IoT nodes, and experimental results confirm the protocol's superiority, demonstrating a 28% reduction in computation time and a 34% reduction in storage overhead compared to existing AES–RSA solutions, while successfully maintaining high data authenticity and strong resistance to tampering.