| In recent years,in order to solve the problems of high cost and low efficiency in the "last mile" delivery,crowdsourcing logistics and drone delivery logistics have been research hotspots.The crowdsourcing drone delivery system combines the advantages of crowdsourcing logistics and drone delivery logistics,not only can effectively integrate drone resources and eliminate the need for small distribution stations with drone delivery requirements to purchase a large number of drones,but also can improve the delivery efficiency and reduce the total delivery cost.However,the existing crowdsourcing systems do not consider the particularity of drone delivery tasks on the one hand,and on the other hand,they generally use a central server as the crowdsourcing platform,which is prone to problems such as single point of failure,difficulty in arbitration,and leakage of a large number of user privacy data.Their architecture is not suitable for porting to the crowdsourcing drone delivery system.In view of the above problems,this thesis has launched the following two aspects of research.On the one hand,this thesis comprehensively considers crowdsourcing architecture and the particularity of the drone delivery tasks,and puts forward a blockchain-based crowdsourcing drone delivery system framework.The framework firstly leverages blockchain technology to build a decentralized crowdsourcing platform,secondly designs the business process of crowdsourcing drone delivery,and finally deploys smart contracts closely related to the business process to monitor and control the execution of each business process.The prototype system based on the Ethereum platform verifies the feasibility of the framework.At the same time,security analysis shows that the framework can not only resist Sybil attacks and Distributed Denial of service attacks to a certain extent,but also eliminate single point of failure,realize automated business processes and provide user identity anonymity.On the other hand,although blockchain can provide users with identity anonymity,it does not have unlinkability,and the protection of user identity privacy is relatively weak.Therefore,under the crowdsourcing drone delivery system framework based on blockchain,this thesis proposes a privacy protection scheme on the blockchain based on random pseudo-identities.This scheme firstly dynamically generates random pseudo-identities and private keys for users,and designs the digital signature and authentication protocols based on elliptic curve cryptography,so that users can use unrelated pseudo-identities to participate in different order tasks.Secondly,the scheme uses the blockchain proxy server to uniformly forward the user’s request for invoking the smart contract,eliminating any possibility of internal attackers linking the user’s multiple order records.Finally,the scheme dynamically updates the user’s reputation value based on the feedback of the smart contract,and restricts users whose reputation value is below the threshold from participating in the system,reducing the existence of potential attackers from the source.Security analysis and performance evaluation show that this scheme can realize the unlinkability of transactions on the blockchain at a low time cost without affecting the smart contract monitoring crowdsourcing business process.In summary,this thesis designs the blockchain-based crowdsourcing drone delivery system framework and privacy protection scheme,which not only eliminates the single point of failure,realizes the automated business process,provides user identity anonymity,but also realizes the unlinkability of transactions on the blockchain,and strengthens the protection of crowdsourcing user identity privacy. |
