Secure Lightweight Authentication Framework for Resource-Constrained IoT Nodes Using Blockchain-Assisted Key Management

Abstract

Smart environments have increased the difficulties in authentication and key management by the rapid proliferation of resource constrained or Internet of Things (IoT) nodes. Traditional on-demand centralised public key infrastructures have single points of failure and can scale only to a very small size, whereas fully on-chain blockchain-based proposals present high computational overhead to cost-effective devices and high communication overhead to allow both. This article describes an authenticated lightweight protection structure based on elliptic curve cryptography (ECC) and key anchoring with the aid of block chain to implement the decentralised trust with a minimum overhead. The hybrid architecture proposed has the public key hash stored on a distributed ledger, and mutual authentication on off-chain and determination of session keys up towards efficient ECC-based challenge-response mechanisms. Formal system and threat model are created and an analytic energy consumption model is obtained to compute the cost of computations and transmission within realistic IoT limitations. Analysis of performance indicates that the framework uses less authentication energy and communication overhead than to corresponding blockchain-integrated methods that represent systems and guarantees forward secrecy and replay resistance, impersonation, and man-in-the-middle attacks. The scheme provides scalable, constant-time authentication, and can therefore be used in large-scale applications of resource-constrained IoT networks.