Scalable and secure crowdsourcing atop blockchain via off-chain payment
Anxin Zhou, Cong Wang, Xiaohua Jia · Journal of Blockchain Research · 2022
Blockchain facilitates atomic exchange by serving as a decentralized coordinator.It recently has been applied to crowdsourcing for settling the payment between the mutually untrusted data collector and data providers.However, this is still not practical due to the blockchain's poor performance.This paper presents a crowdsourcing system that uses the blockchain in a secure and scalable fashion.A crowdsourcing task can involve an unlimited number of data providers but with a constant transaction cost.For this purpose, we design an off-chain payment system based on trusted hardware.In this way, the data collector can use offchain payment for crowdsourcing, and the blockchain mainly performs lightweight verification to ensure honest payment.We implement and evaluate an application of text data collection.The evaluation shows the desirable performance.