| With the rapid development of satellite technology and the high transmission efficiency of LEO(Low-Earth-Orbit)satellites,LEO satellite communication has been received increasing attentions.Satellites in LEO can still provide broadband communication where there is no ground base station,and provide high-quality services to anyone at anytime and anywhere.However,the distributed nature of LEO satellite networks creates various security vulnerabilities,such as data leaks.Frequent switching of satellite-to-ground links brings challenges to satellite authentication of user identity,while traditional authentication methods are vulnerable to single point of failure.In addition,since each satellite group may not belong to a unified owner,how to effectively control the spread of user information among satellite networks is also a challenge.However,the traditional privacy protection method is based on cryptography to protect the information itself,without considering the information dissemination process.In this paper,the security mechanisms of identity authentication and privacy protection in LEO satellite network are studied,and the security methods of identity authentication and privacy protection based on blockchain are designed respectively.The main work is as follows.(1)Aiming at the problem that frequent switching of satellite-ground links brings great challenges to the authentication of LEO satellite networks,this paper proposes A BlockchainBased Authentication Method Using Cryptocurrency Technology in LEO Satellite Networks(BAC).Using cryptocurrency technology,the problems of satellite service interruption time and authentication security caused by user access authentication in the scene of frequent switching between satellite and ground users are solved.First of all,cryptocurrency technology is introduced to design the registration stage,initial authentication stage and switching authentication stage of the authentication process.Using currency transaction as the certificate of identity authentication not only improves the security of authentication,but also improves the efficiency of switching authentication.Secondly,in the network topology,the satellite constellation is divided into multiple regions to improve the efficiency of block consensus.Thirdly,the key security and the security against replay attack,denial of service attack,impersonation attack and man-in-the-middle attack are analyzed.Finally,the method is tested by NS2 network simulation platform,and the simulation results show that the identity authentication method can greatly shorten the response time of handover authentication,and significantly reduce the block generation time and network throughput.(2)In view of the problem that information owners are faced with losing control of information dissemination when user information is spread across multiple service platforms,this paper proposes A Blockchain-Based Privacy Protection Method Using Smart Contracts Technology in LEO Satellite Networks(BPPSC).Intelligent contract technology is adopted to solve the problem that users can’t control information dissemination in cross-platform information dissemination scenarios.Firstly,the smart contract is introduced to design the user registration stage,information uploading stage,information dissemination stage and information termination stage of information dissemination control.Using smart contract as a method to control information dissemination not only improves the controllability of information dissemination,but also improves the efficiency of information inquiry.Secondly,in the process of communication,the scope of communication is limited based on users’ privacy preferences,so as to improve the security of users’ information dissemination.Thirdly,the key security of the method and the security against malicious information owner attack,malicious disseminator attack,malicious service platform attack and man-in-the-middle attack are analyzed.Finally,the effectiveness and security of the privacy protection method are proved by the simulation results and security analysis of the Ethereum blockchain test network and NS2 network,and the response delay of the transaction uplink is significantly reduced.To sum up,in identity authentication,this paper uses blockchain-based cryptocurrency technology as a voucher to prove the user’s identity,so as to achieve rapid identity authentication.In the privacy protection method,the intelligent contract technology is used to automatically execute the scheduled transaction in the form of program to control the information dissemination process,so as to realize privacy protection. |
