Certificate-less key secure communication protocol for internet of things based on smart contracts

Abstract

With the rise of the internet of things (IoT), ensuring operational efficiency and security for resource-constrained nodes has become crucial. This paper proposes two certificate-less key agreement protocols based on confidential message entanglement, addressing limitations of traditional key management such as certificate reliance and high computational costs. A smart contract-driven, dynamically switchable distributed key management framework is also introduced to enhance adaptability under varying attack frequencies. Simulation results indicate reduced communication and computational overhead. Protocols 1 and 2 show computational losses of 5.53 and 6.47, respectively, while smart contract-based scenarios range from 4.28 to 4.39. In smart agriculture applications, dynamic switching reduced overhead from 6.47 to 4.28, optimising performance by 33.84%. The research supports the development of lightweight, secure, and adaptable communication frameworks for IoT applications in smart cities, industrial monitoring, and telemedicine, offering strong theoretical and practical value.