PDMSC: privacy-preserving decentralized multi-skill spatial crowdsourcing

PurposeThe purpose of this paper is to study the following two issues regarding blockchain crowdsourcing. First, to design smart contracts with lower consumption to meet the needs of blockchain crowdsourcing services and also need to design better interaction modes to further reduce the cost of blockchain crowdsourcing services. Second, to design an effective privacy protection mechanism to protect user privacy while still providing high-quality crowdsourcing services for location-sensitive multiskilled mobile space crowdsourcing scenarios and blockchain exposure issues.Design/methodology/approachThis paper proposes a blockchain-based privacy-preserving crowdsourcing model for multiskill mobile spaces. The model in this paper uses the zero-knowledge proof method to make the requester believe that the user is within a certain location without the user providing specific location information, thereby protecting the user's location information and other privacy. In addition, through off-chain calculation and on-chain verification methods, gas consumption is also optimized.FindingsThis study deployed the model on Ethereum for testing. This study found that the privacy protection is feasible and the gas optimization is obvious.Originality/valueThis study designed a mobile space crowdsourcing based on a zero-knowledge proof privacy protection mechanism and optimized gas consumption.