A Blockchain-Based Authentication Scheme for 5G-Enabled IoT

5G cellular network is becoming a preferred technology for communication in deployments of the Internet of Things (IoT). However, 5G cellular network is essentially designed for cellular communication. Therefore, there are several areas in IoT over 5G cellular network, where there is scope for further improvement. One such area is development of efficient security mechanisms for authentication of the IoT devices. The authentication protocol currently being used in 5G cellular network maintains the security credentials of the devices at the home network in a centralised manner. Therefore, every time a device needs to be authenticated, the home network has to be communicated. However, considering the IoT scenario where there is large scale deployment of devices, frequent communication with the home network may result in increased communication latency. In this paper, we propose an authentication scheme where security credentials of the IoT devices are stored in a decentralized way using blockchain technology. The scheme is found to be safe and secured, through an informal and a formal security analysis using scyther tool. The smart contracts used in the scheme, when deployed in the ethereum test network, are also found to be efficient. Through experimental performance analysis, the scheme is found to have attained reduced communication latency compared to the existing protocols.