Research And Application Of Blockchain-based Data Trading Optimization

In the intelligent era,the wide deployment of smart devices and social applications make users enjoy a much more convenient life.Meanwhile,the smart devices and social applications generate and collect massive personal data and surrounding environment information of users in real time.With the development of machine learning and data mining,these data can be utilized for data analysis and valuable information mining for users,for example,forecasting healthcare condition of users.Moreover,based on users' data,service providers can analyze their service quality and improve their service ability through data analysis.In general,data is becoming an dispensable driving force for the development of all works of life.In order to make good use of data,data trading has been presented to sell or purchase expected data for users.Some data trading platforms and mechanisms are also designed by researchers.However,the proposed data trading methods are unable to meet the requirement of security and privacy.Some problems have to be solved as follows.The one is to establish a more secure data trading platform and design a more efficient data trading mechanism.The previous works mainly focus on the centralized data trading platform,which is easily to suffer from single point of failure,typical distributed denial of service(DDo S)and so on.Moreover,the security of users' data and trading information cannot be guaranteed.The other is to design a reasonable incentive mechanism to encourage users to join the data trading.The collected data generally consists of lots of privacy information of users.In order to compensate users for potential privacy loss,the incentive mechanism is required in data trading.To solve the above problems,we study and integrate blockchain technology into data trading,which can realize the secure and efficient data trading.The main works of this thesis are summarized as follows.(1)We design a general consortium blockchain-based data storage and trading platform,namely DTChain.Due to the remarkable characteristic of decentralization and distribution,DTChain can be utilized to solve the security problems in the centralized data trading platform.In this platform,we divide DTChain into six layers,which includes data layers,network layer,consensus layer,incentive layer,contract layer and application layer.In each layer,we introduce the design principle and composition in detail in this thesis.(2)Based on DTChain,we further explore data trading in mobile healthcare,and design a smart contract-based data trading mechanism for mobile healthcare.With the characteristic of automatic execution,openness and transparency,the designed smart contract can ensure secure data trading in mobile healthcare.(3)To encourage users to join the data trading,we also design the incentive mechanism for data trading in mobile healthcare.Through considering privacy preference and encryption level of data providers,we establish the utility functions of data providers and data collectors,respectively.Then,we use Stackelberg game to formulate the data trading problem among a data collector and multiple data providers.Finally,numerical results demonstrate that the designed incentive mechanism is effective.(4)Finally,we implement necessary security and efficiency analysis of our proposed data trading platform,i.e.,DTChain.Through the analysis,we can find our scheme can meet the requirement of security,privacy and efficiency of data trading.We also evaluate the performance of the smart contract-based data trading scheme in mobile healthcare,which proves our scheme has the advantage of low energy consumption,high efficiency and high security.