| 摘要: |
| 众包作为一种基于群智感知技术的数据收集和任务分配模式,可有效提高任务完成的灵活性、多样性,节省运营成本,在移动医疗、环境监测、智能交通等领域有广阔的应用前景。目前的众包形态包括集中式和分布式,集中式众包的云服务器面临中心信任和安全问题,且存在因遵循服务器利益最大化原则导致众包工作者参与积极性低、任务收敛慢的性能问题;分布式众包面临着任务分配不均衡、分布式数据难以保持一致性等问题。针对以上问题,本文提出一种基于区块链的分布式众包机制,具体体现为:(1)建立基于区块链的众包模型,充分利用区块链去中心化、不可篡改等优势,解决中心服务器信任问题,适用于分布式的群智感知网络应用;(2)研究基于PBFT的数据同步机制,在保证数据一致性和算法容错性前提下,提高了共识效率;(3)设计服务质量评分算法和基于服务质量评分的任务分配和报酬发放机制,最大化接包方利益,调动参与者的积极性,提高服务完成率和服务质量。本文为阐明所提区块链众包机制的安全性,分别对系统的抗攻击能力、共识算法的安全性、服务质量评分算法的正确性分别进行了理论分析;为探讨机制的实用性,搭建Hyperledger Fabric并构造多节点环境进行算法仿真,验证了本文共识算法性能的优越性和多任务多用户条件下众包质量及效率上的提升。 |
| 关键词: 众包 区块链 共识 服务质量评分 安全性 可行性 |
| DOI：10.19363/J.cnki.cn10-1380/tn.2023.08.15 |
| 投稿时间：2021-02-16修订日期：2021-05-19 |
| 基金项目:本课题得到国家重点研发计划(No. 2019YFB1005204)项目资助。 |
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| Blockchain-based Crowdsourcing Mechanism |
| ZHANG Zhujun,ZHU Dali,FAN Wei,MI Baoxin,PENG Cheng |
| Institute of Information Engineering, Chinese Academy of Sciences, Beijing 100093, China;School of Cyber Security, University of Chinese Academy of Sciences, Beijing 100049, China |
| Abstract: |
| Crowdsourcing, as a data collection and task allocation mode based on group intelligence perception technology, can effectively improve the flexibility and diversity of task completion, save operating costs, and has broad application prospects in mobile medical, environmental monitoring, intelligent transportation and other fields. The current forms of crowdsourcing include centralized crowdsourcing model and distributed crowdsourcing model. Centralized crowdsourcing cloud servers face central trust and security issues, and there are performance problems such as low enthusiasm for crowdsourcing workers and slow task convergence due to the principle of maximizing server benefits, while distributed crowdsourcing faces issues such as imbalanced task allocation and difficulty in maintaining consistency of distributed data. In response to the above problems, this paper proposes a blockchain-based distributed crowdsourcing mechanism, which is specifically embodied as: (1) Establish a crowdsourcing model based on the blockchain, make full use of the advantages of blockchain decentralization and non-tampering, to solve the problem of trust in the central server, which is suitable for distributed swarm-aware network applications; (2) Research on PBFT-based data synchronization mechanisms to improve consensus efficiency under the premise of ensuring fault tolerance and data consistency; (3) Design a service quality scoring algorithm and a reward mechanism based on service quality scoring to maximize the benefits of contractors, mobilize participants’ enthusiasm, and improve service completion rate and service quality. To clarify the security of the proposed blockchain crowdsourcing mechanism, this paper conducts theoretical analysis on the system’s anti attack ability, the security of consensus algorithms, and the correctness of service quality scoring algorithms, respectively. To explore the practicality of the mechanism, Hyperledger Fabric has been built and a multi node environment has been designed for algorithm simulation, verifying the superior performance of the consensus algorithm in this paper and the improvement of crowdsourcing quality and efficiency under multi task and multi user conditions. |
| Key words: crowdsourcing blockchain consensus service quality score security practicality |
