Blockchain-Enabled Scalable Data Marketplaces for the Internet of Things

Abstract

As the Internet of Things (IoT) expands, so does the volume of valuable data it generates. Yet most of this data remains siloed, underutilized, or monopolized by platform providers. A decentralized data sharing infrastructure is needed to ensure equitable access, trust, and economic incentive for data exchange. This paper introduces the Blockchain-based IoT Data Marketplace (BIDM), a scalable, decentralized platform that allows IoT data producers and consumers to engage in secure and trustworthy data transactions. Built on Ethereum with a Proof-of-Authority consensus mechanism and leveraging smart contracts, BIDM ensures data ownership, fair pricing, secure access control, and transparent transaction logging. It supports both individual data purchases and stream-based subscriptions, offering flexibility to diverse consumers. The system is rigorously evaluated through synthetic and real-world IoT workloads, including integration with the SmartSantander platform. Performance results demonstrate the BIDM's viability under high loads, with consistent execution times and minimal scalability impact. This work provides a significant step toward secure, interoperable, and efficient blockchain-enabled data marketplaces for the IoT ecosystem.