EdgeLinker: Practical Blockchain-based Framework for Healthcare Fog Applications to Enhance Security in Edge-IoT Data Communications

TL;DR

This paper addresses security and privacy challenges in healthcare IoT data processed at the fog layer by proposing EdgeLinker, a practical blockchain-based framework that integrates Proof-of-Authority consensus on Ethereum, smart-contract-based access control, and a secure edge-to-fog communication channel. Implemented on a real fog testbed, EdgeLinker demonstrates strong data confidentiality, integrity, and availability, achieving a $35 ext{\%}$ improvement in read times with near-zero write-time overhead and scalable throughput as fog nodes increase. The framework supports legacy devices through fog-based mediation, uses a local incentive coin for miners, and deploys via Docker Swarm for efficient orchestration. Overall, EdgeLinker offers an affordable, scalable solution that can integrate with existing healthcare systems to enhance security, privacy, and data ownership in edge-IoT healthcare data communications.

Abstract

The pervasive adoption of Internet of Things (IoT) has significantly advanced healthcare digitization and modernization. Nevertheless, the sensitive nature of medical data presents security and privacy challenges. On the other hand, resource constraints of IoT devices often necessitates cloud services for data handling, introducing single points of failure, processing delays, and security vulnerabilities. Meanwhile, the blockchain technology offers potential solutions for enhancing security, decentralization, and data ownership. An ideal solution should ensure confidentiality, access control, and data integrity while being scalable, cost-effective, and integrable with the existing systems. However, current blockchain-based studies only address some of these requirements. Accordingly, this paper proposes EdgeLinker; a comprehensive solution incorporating Proof-of-Authority consensus, integrating smart contracts on the Ethereum blockchain for access control, and advanced cryptographic algorithms for secure data communication between IoT edge devices and the fog layer in healthcare fog applications. This novel framework has been implemented in a real-world fog testbed, using COTS fog devices. Based on a comprehensive set of evaluations, EdgeLinker demonstrates significant improvements in security and privacy with reasonable costs, making it an affordable and practical system for healthcare fog applications. Compared with the state-of-the-art, without significant changes in the write-time to the blockchain, EdgeLinker achieves a 35% improvement in data read time. Additionally, it is able to provide better throughput in both reading and writing transactions compared to the existing studies. EdgeLinker has been also examined in terms of energy, resource consumption and channel latency in both secure and non-secure modes, which has shown remarkable improvements.

Figures (6)

• Figure 1: Architecture of EdgeLinker: Cloud Data Center, Fog Layers, IoT Devices.
• Figure 2: Experimental Environment.
• Figure 3: Sequence of Requests in the Experimental Scenario.
• Figure 4: Comparison of Processing Delay and Processing Time for Reading.
• Figure 5: Comparison of Processing Delay and Processing Time for Writing.