Citation: Bobde, Y.; Narayanan, G.; Jati, M.; Raj, R.S.P.; Cviti´ c, I.; Perakovi´ c, D. Enhancing Industrial IoT Network Security through Blockchain Integration. Electronics 2024, 13, 687. https:// doi.org/10.3390/electronics13040687 Academic Editors: Giovanni Crupi and Yung-Fa Huang Received: 23 December 2023 Revised: 28 January 2024 Accepted: 5 February 2024 Published: 7 February 2024 Copyright: © 2024 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). electronics Article Enhancing Industrial IoT Network Security through Blockchain Integration Yash Bobde 1 , Gokuleshwaran Narayanan 1 , Manas Jati 1 , Raja Soosaimarian Peter Raj 1, * , Ivan Cviti´ c 2, * and Dragan Perakovi´ c 2 1 School of Computer Science and Engineering, Vellore Institute of Technology, Vellore 632014, Tamil Nadu, India; yashsantosh.bobde2020@vitstudent.ac.in (Y.B.); gokuleshwaran.n2020@vitstudent.ac.in (G.N.) 2 Department of Information and Communiation Traffic, Faculty of Transport and Traffic Sciences, University of Zagreb , Vukeli´ ceva 4, 10000 Zagreb, Croatia; dragan.perakovic@fpz.unizg.hr * Correspondence: raja.sp@vit.ac.in (R.S.P.R.); ivan.cvitic@fpz.unizg.hr (I.C.) Abstract: In the rapidly evolving landscape of industrial ecosystems, Industrial IoT networks face increasing security challenges. Traditional security methods often struggle to protect these networks adequately, posing risks to data integrity, confidentiality, and access control. Our research introduces a methodology that leverages blockchain technology to enhance the security and trustworthiness of IoT networks. This approach starts with sensor nodes collecting and compressing data, followed by encryption using the ChaCha20-Poly1305 algorithm and transmission to local aggregators. A crucial element of our system is the private blockchain gateway, which processes and classifies data based on confidentiality levels, determining their storage in cloud servers or the Interplanetary File System for enhanced security. The system’s integrity and authenticity are further reinforced through the proof of authority consensus mechanism. This system employs Zero Knowledge Proof challenges for device authorization, optimizing data retrieval while maintaining a delicate balance between security and accessibility. Our methodology contributes to mitigating vulnerabilities in Industrial IoT networks and is part of a broader effort to advance the security and operational efficiency of these systems. It reflects an understanding of the diverse and evolving challenges in IoT security, emphasizing the need for continuous innovation and adaptation in this dynamic field. Keywords: Industrial IoT networks; blockchain technology; data security and integrity; ChaCha20-Poly1305 encryption; private blockchain gateway; Interplanetary File System; proof of authority consensus; Zero Knowledge Proof; data confidentiality; access control 1. Introduction The Industrial Internet of Things (IoT) has ushered in a new era in the industrial sector, marked by the extensive integration of interconnected devices and systems. This revolution is redefining industry standards through real-time data collection, processing, and decision- making capabilities. However, the rapid expansion of IoT networks introduces significant challenges, particularly in the realms of data security, integrity, and privacy, which are crucial in industrial settings [1]. In this context, blockchain technology, renowned for its decentralized ledger system, emerges as a potent solution to these burgeoning challenges [2]. Its ability to ensure data integrity, transparency, and trustworthiness positions it as an ideal candidate to secure sensitive industrial data [3]. This research paper delves into the potential of blockchain in enhancing the security of IoT networks. We focus on employing private blockchain gateways to safeguard the data flow from sensor nodes to core processing units, integrating advanced cryptographic techniques like Zero Knowledge Proof (ZKP) to authenticate data and restrict access to authorized entities. Electronics 2024, 13, 687. https://doi.org/10.3390/electronics13040687 https://www.mdpi.com/journal/electronics