Research On Identity Management And Privacy Protection Method Based On Blockchain

More and more applications related to smart home,smart medical,smart power grid and smart mobile collect,store,and manage user identity data.At present,most Internet applications still adopt the centralized identity management system,and identity data is tampered and abused,which seriously threatens users’ privacy.In view of the above issues,the identity management method based on blockchain effectively solves the issue of identity data tampering,but the user’s identity data stored on the blockchain makes it open and transparent,and there is still the risk of privacy disclosure.Based on this,guided by the principle of self-sovereign identity,this thesis studies the identity management and privacy protection methods based on blockchain.The main work is as follows:(1)Combining blockchain with self-sovereign identity management,this thesis proposes an identity management scheme based on blockchain that endows users with autonomy and privacy protection ability.To solve the issue of transparency of blockchain data storage,a method is proposed to separate on-chain credentials from off-chain credentials,to avoid exposing privacy of on-chain public data.Aiming at the issue of over-exposure in the process of user identity data sharing,a signature-based selective disclosure method is proposed to give users the right of control and choice in the process of identity data sharing,minimize the disclosure of identity information,achieve the purpose of privacy protection.(2)In order to verify the authenticity of user identity,the thesis studies the method of identity data trust management based on blockchain,including the trusted release of identity data,trusted verification and other methods.According to the needs of decentralized identity management and from the perspective of data management,the participants and trust operations of identity data are defined.By studying the authenticity representation method of identity data,the construction method of block and chain structure and the authenticity verification method,an identity trust management scheme based on blockchain is designed.(3)In order to verify the feasibility and practicability of the proposed scheme,this thesis designs and implements a self-sovereign identity management system based on the blockchain platform of Ethereum and uses the smart contract technology supported by it.The simulation test results demonstrate the correctness and effectiveness of the research and design method.