Blockchain-Based Secure Identity for IoT Networks

Abstract

This review article examines the state of blockchain enabled identity management in Internet of Things (IoT) networks, focusing on decentralized and secure mechanisms for device identification, authentication, and access control. Traditional centralized identity systems face limitations such as single points of failure, scalability bottlenecks, and vulnerability to breaches. We systematically survey recent literature on blockchain based frameworks applied to IoT, categorizing approaches by blockchain platform, identity credential models, consensus mechanisms, and smart contract implementations. The analysis highlights key performance metrics such as system latency, throughput, resource overhead, and energy consumption, and compares existing prototypes deployed across diverse IoT scenarios. We assess the security and privacy implications, including resistance to spoofing, Sybil attacks, unauthorized access, data tampering, and insider threats. Additionally, the review identifies open research challenges such as managing identity lifecycle in constrained devices, achieving interoperability across heterogeneous networks, balancing decentralization with scalability, and integrating with emerging technologies like edge computing and zero knowledge proofs. Finally, we offer recommendations for future research directions and practical deployment strategies to advance blockchain based identity solutions in IoT ecosystems. Our comprehensive synthesis aims to guide researchers and practitioners in developing robust, scalable, and trustworthy identity frameworks using blockchain for the evolving IoT landscape.

Introduction

The Internet of Things (IoT) is growing rapidly, with over 30 billion devices expected by 2030. As these devices generate vast data and interact autonomously, secure and scalable identity management becomes essential. Traditional centralized identity systems face major limitations, such as single points of failure, poor scalability, and vulnerability to attacks.

To address this, blockchain technology has emerged as a promising alternative, offering decentralized, tamper-resistant identity management. Through distributed ledgers and smart contracts, devices can register, authenticate, and manage identities without relying on centralized authorities. Platforms like Ethereum, Hyperledger Fabric, IOTA, and Sovrin support various architectures for identity solutions—public, private, or consortium-based.

However, challenges remain:

• Resource constraints on IoT devices (limited energy, processing, storage)

• Scalability and high latency of public blockchains

• Privacy concerns over storing identity data on immutable ledgers

• Lack of standardization for decentralized identity models (like DIDs and SSI)

• Complex revocation and key management

Despite these, blockchain offers several advantages for IoT:

• Decentralized trust (no single authority)

• Immutable and auditable identity records

• Smart contracts for automation

• Strong cryptographic security

• Self-sovereign identity control

• Cross-platform interoperability

Applications span smart homes, healthcare, industrial IoT, supply chains, mobility, and energy systems—where secure and automated identity management is critical.

A review of 58 studies (2016–2024) showed that:

• Most use permissioned blockchains (e.g., Hyperledger) for better performance

• About 64% implement smart contracts for identity tasks

• Around 28% use SSI and DIDs

• Lightweight consensus methods like PBFT and DPoS are preferred for low-power devices

Conclusion

Blockchain technology presents a transformative opportunity to address longstanding challenges in IoT identity management, offering decentralized trust, improved transparency, and enhanced security. This review has synthesized current research efforts, highlighting the diversity of blockchain architectures, identity models, and cryptographic techniques employed to secure identity in resource-constrained IoT environments. While significant progress has been made, especially in the use of smart contracts and permissioned ledgers, practical deployment remains limited by issues such as scalability, energy efficiency, interoperability, and regulatory compliance. The adoption of emerging paradigms like self-sovereign identity and decentralized identifiers demonstrates promising direction, yet integration with constrained IoT hardware and legacy systems is still an open problem. Future research should focus on lightweight consensus mechanisms, privacy-preserving identity protocols, standardized identity frameworks, and cross-chain interoperability to bridge the gap between academic innovation and industrial adoption. In conclusion, while blockchain offers a compelling foundation for secure IoT identity systems, realizing its full potential will require interdisciplinary collaboration, technical refinement, and real-world validation.

References

[1] Lee and K. Lee, \"The Internet of Things (IoT): Applications, investments, and challenges for enterprises,\" Business Horizons, vol. 58, no. 4, pp. 431–440, 2015. [2] M. Ammar, G. Russello, and B. Crispo, \"Internet of Things: A survey on the security of IoT frameworks,\" Journal of Information Security and Applications, vol. 38, pp. 8–27, 2018. [3] M. Crosby et al., \"Blockchain technology: Beyond bitcoin,\" Applied Innovation, vol. 2, pp. 6–10, 2016. [4] K. Christidis and M. Devetsikiotis, \"Blockchains and smart contracts for the Internet of Things,\" IEEE Access, vol. 4, pp. 2292–2303, 2016. [5] Sovrin Foundation, “The Sovrin Protocol and Token Whitepaper,” 2020. [Online]. Available: https://sovrin.org [6] H. M. Nguyen, M. Laurent, and A. Nguyen, \"A survey on blockchain applications for the Internet of Things,\" IEEE Access, vol. 9, pp. 143250–143274, 2021.

Copyright

Copyright © 2025 M Rupasri, T Meenakshi, Y Gayatri. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.