ABCrowd An Auction Mechanism on Blockchain for Spatial Crowdsourcing

Abstract

In this paper, a fully distributed auction-blockchain-based crowdsourcing framework is proposed-ABCrowd. In a typical crowdsourcing framework, independent workers compete to be allocated requesters' tasks. These workers advertise their costs to the centralized platform, which then decides the final allocation of tasks. While performing the allocation, centralized platforms face two main challenges: 1) how to ensure trusted execution for the allocation of tasks, and 2) how to motivate workers to declare their truthful costs. To address these challenges, ABCrowd proposes to run the crowdsourcing platform entirely on Ethereum Blockchain while incorporating auctions. Blockchain and smart contracts guarantee trusted execution for the allocation through autonomous and transparent on-Chain execution. ABCrowd uses the Repeated-Single-Minded Bidder (R-SMB) auction mechanism, which motivates workers to bid truthfully before allocating them and calculating their payments. R-SMB is an approximation of the optimized off-Chain Vickrey-Clarke-Groves (VCG) mechanism in terms of maximized profit. It entails repeating the Single-Minded Bidder (SMB) auction mechanism to meet the allocation requirement of crowdsourcing applications. ABCrowd is implemented and evaluated using Solidity on a private Ethereum Blockchain, where a real publicly available dataset is used. The proposed on-Chain R-SMB auction mechanism is compared to the off-Chain VCG mechanism, where the results show that R-SMB provides similar performance to VCG in terms of the average number of allocated tasks. Furthermore, R-SMB outperforms VCG in workers' travelled distance and requesters' costs, at a low execution cost. INDEX TERMS Crowdsourcing, blockchain, smart contracts, auction.

Formal Modeling and Verification of a Blockchain-Based Crowdsourcing Consensus Protocol

“…Confidentiality and identity anonymity are achieved using searchable encryption. An auction-blockchain-based crowdsourcing technique, ABCrowd is presented to execute crowdsourcing on Ethereum blockchain including auctions [51]. It utilizes repeated bidders auction technique which allows truthful bidding.…”

TSWCrowd: A Decentralized Task-Select-Worker Framework on Blockchain for Spatial Crowdsourcing

“…This is mainly due to the limited computing scale of Blockchain, and a large number of computing processes are still executed off-chain. [31] puts forward a completely distributed crowdsourcing framework, which executes auctions on Blockchain, and replaces centralized auction platform with intelligent contracts of Blockchain Ethereum. However, after the auction stage, the model only considers the bidding price and the distance between workers and tasks, ignoring the important factors such as workers' reputation and completion time, so the rationality of workers' selection needs to be improved.…”

“…[35] proposes a novel block symbiosis mechanism, which can greatly reduce the computational overhead and realize completely distributed and decentralized management. [31] uses the repeated bidder bidding mechanism, the auction algorithm is deployed in the blockchain environment, and the task allocation strategy is optimized. However, the privacy of users is not protected, and only the location factor is considered in the selection criteria of bidding workers, while other important attributes such as completion time are ignored.…”

“…[34] The task allocation scheme of the model is to allocate tasks according to the time sequence requested by workers, which does not guarantee the maximization of the rationality of workers' task allocation. Some crowdsourcing models in blockchain environment combine apply auction mode to allocate tasks, [31] using repeated bidders bidding mechanism, deploying auction algorithm in blockchain environment, optimizing task allocation strategy, but not protecting user privacy, and only considering location factor in bidding selection criteria, ignoring other important attributes such as workers' reputation and compensation. [37] introduced a distributed service to deliver complex problems for cloud users.…”

Blockchain and AI-Based Solutions to Combat Coronavirus (COVID-19)-Like Epidemics: A Survey

“…These features of blockchain would ensure correct data collection and thus support reliable COVID-19 analysis. Also, the incentive mechanisms offered by blockchain can be very useful to provide solutions for fighting COVID-19, by combining with crowdsourcing/crowdsensing technologies [13] – [16] . Indeed, crowdsourcing enables to use the crowd to collect information that is needed for the detection of COVID-19 patients.…”