TY - JOUR

T1 - Blockchain-Based Reliable and Privacy-Aware Crowdsourcing with Truth and Fairness Assurance

AU - Wu, Haiqin

AU - Dudder, Boris

AU - Wang, Liangmin

AU - Sun, Shipu

AU - Xue, Guoliang

N1 - Publisher Copyright: IEEE

PY - 2022

Y1 - 2022

N2 - The ubiquity of crowdsourcing has reshaped the static sensor-enabled data sensing paradigm with cost efficiency and flexibility. Still, most existing triangular crowdsourcing systems only work under the centralized trust assumption and suffer from various attacks mounted by malicious users. Although incorporating the emerging blockchain technology into crowdsourcing provides a possibility to mitigate some of the issues, how to concretely implement the crucial components and their functionalities in a verifiable and privacy-aware manner remains unaddressed. In this paper, we present BRPC, a blockchainbased decentralized system for general crowdsourcing. BRPC integrates the confident-aware truth discovery algorithm to provide task requesters with reliable task truths while evaluating each worker’s data quality. To mitigate biased evaluation of malicious requesters, we propose a privacy-aware verification protocol leveraging the Threshold Paillier Cryptosystem, with which a certain number of workers can collaboratively verify the evaluation results without knowing any sensory data. Furthermore, we define the three roles of a user and elaborate a comprehensive reputation evaluation model enforced by smart contracts for its trustworthy running. Financial and social incentives are both offered to motivate users’ honest participation. Finally, we implement a prototype of BRPC and deploy it on the Ethereum blockchain. Theoretical analyses and experiment results show its security and practicality.

AB - The ubiquity of crowdsourcing has reshaped the static sensor-enabled data sensing paradigm with cost efficiency and flexibility. Still, most existing triangular crowdsourcing systems only work under the centralized trust assumption and suffer from various attacks mounted by malicious users. Although incorporating the emerging blockchain technology into crowdsourcing provides a possibility to mitigate some of the issues, how to concretely implement the crucial components and their functionalities in a verifiable and privacy-aware manner remains unaddressed. In this paper, we present BRPC, a blockchainbased decentralized system for general crowdsourcing. BRPC integrates the confident-aware truth discovery algorithm to provide task requesters with reliable task truths while evaluating each worker’s data quality. To mitigate biased evaluation of malicious requesters, we propose a privacy-aware verification protocol leveraging the Threshold Paillier Cryptosystem, with which a certain number of workers can collaboratively verify the evaluation results without knowing any sensory data. Furthermore, we define the three roles of a user and elaborate a comprehensive reputation evaluation model enforced by smart contracts for its trustworthy running. Financial and social incentives are both offered to motivate users’ honest participation. Finally, we implement a prototype of BRPC and deploy it on the Ethereum blockchain. Theoretical analyses and experiment results show its security and practicality.

KW - blockchain

KW - Blockchains

KW - Crowdsourcing

KW - Cryptography

KW - Data integrity

KW - privacy.

KW - Reliability

KW - Smart contracts

KW - Task analysis

KW - truth discovery

KW - verifiability

U2 - 10.1109/JIOT.2021.3097950

DO - 10.1109/JIOT.2021.3097950

M3 - Journal article

AN - SCOPUS:85111044561

VL - 9

SP - 3598

EP - 3598

JO - IEEE Internet of Things Journal

JF - IEEE Internet of Things Journal

SN - 2327-4662

IS - 5

ER -