[Paper Review] A lightweight blockchain-based access control scheme for integrated edge computing in the internet of things

Jie Zhang, Lingyun Yuan+1 more|arXiv (Cornell University)|Nov 12, 2021

Blockchain Technology Applications and Security31 references4 citations

TL;DR

This paper proposes a lightweight blockchain-based access control scheme (ABE-ACS) for edge-integrated IoT systems, combining attribute-based encryption (CP-ABE) with blockchain-enabled smart contracts to enable secure, fine-grained access control. By outsourcing CP-ABE decryption to edge nodes and using a customized PoW consensus, the scheme reduces resource consumption by ~50% compared to prior work, achieving high throughput and low latency in performance tests.

ABSTRACT

In view of the security issues of the Internet of Things (IoT), considered better combining edge computing and blockchain with the IoT, integrating attribute-based encryption (ABE) and attribute-based access control (ABAC) models with attributes as the entry point, an attribute-based encryption and access control scheme (ABE-ACS) has been proposed. Facing Edge-Iot, which is a heterogeneous network composed of most resource-limited IoT devices and some nodes with higher computing power. For the problems of high resource consumption and difficult deployment of existing blockchain platforms, we design a lightweight blockchain (LBC) with improvement of the proof-of-work consensus. For the access control policies, the threshold tree and LSSS are used for conversion and assignment, stored in the blockchain to protect the privacy of the policy. For device and data, six smart contracts are designed to realize the ABAC and penalty mechanism, with which ABE is outsourced to edge nodes for privacy and integrity. Thus, our scheme realizing Edge-Iot privacy protection, data and device controlled access. The security analysis shows that the proposed scheme is secure and the experimental results show that our LBC has higher throughput and lower resources consumption, the cost of encryption and decryption of our scheme is desirable.

Motivation & Objective

• To address the security and scalability challenges in heterogeneous, resource-constrained IoT environments with high data volume and device density.
• To overcome the high computational overhead of traditional blockchains and CP-ABE in IoT settings.
• To enable decentralized, privacy-preserving access control using attribute-based encryption and smart contracts on a lightweight blockchain.
• To reduce the computational burden on IoT devices by outsourcing CP-ABE decryption to edge nodes.
• To ensure policy privacy and integrity through threshold trees and LSSS-based policy encoding on the blockchain.

Proposed method

• Design a lightweight blockchain (LBC) with an optimized proof-of-work (PoW) consensus mechanism to reduce resource consumption and improve throughput.
• Integrate CP-ABE with attribute-based access control (ABAC) into a unified ABE-ACS framework, abstracting attributes as the core access control primitive.
• Use a (t,n) threshold tree and Linear Secret Sharing Scheme (LSSS) to encode and store access policies on the blockchain while preserving policy privacy.
• Outsource computationally intensive CP-ABE encryption and decryption operations to edge nodes, minimizing device-side processing.
• Implement six smart contracts on the LBC to enforce ABAC policies, manage attribute assignments, and enforce penalties for policy violations.
• Apply bilinear pairing-based cryptography in a modified CP-ABE scheme to support flexible, fine-grained access control with private key protection.

Experimental results

Research questions

• RQ1 How can blockchain-based access control be made efficient and deployable on resource-constrained IoT devices in edge-integrated systems?
• RQ2 What is the performance impact of using a lightweight blockchain with an optimized PoW consensus in an IoT edge environment?
• RQ3 Can CP-ABE decryption be securely and efficiently outsourced to edge nodes without compromising data privacy or integrity?
• RQ4 How can access control policies be stored on the blockchain while preserving their confidentiality and enabling dynamic updates?
• RQ5 What is the trade-off between access control flexibility, cryptographic overhead, and system throughput in a heterogeneous IoT-edge architecture?

Key findings

• The proposed lightweight blockchain (LBC) achieves a block production time of approximately 31 seconds per block, with a 50% reduction in computational cost compared to baseline PoW implementations.
• The encryption and decryption times in the ABE-ACS scheme scale linearly with the number of attributes, with negligible increase for data sizes under 1 MB.
• Outsourcing CP-ABE decryption to edge nodes reduces device-side computation by nearly half, as measured by G1 and GT group operations.
• The use of threshold trees and LSSS enables privacy-preserving encoding of access policies on the blockchain, preventing exposure of policy logic.
• The scheme demonstrates higher throughput and lower resource consumption than existing blockchain and CP-ABE solutions, particularly under high-concurrency workloads.
• Performance evaluation confirms that the decryption time for 'OR' policies remains constant regardless of attribute count, while 'AND' policies scale linearly with attribute number.