Research On Attribute Proxy Re-Encryption For Ciphertext Storage And Sharing Scheme Based On Blockchain In Blockchain

Due to the explosive growth of user information,more and more users choose to transfer private information to the cloud,and cloud storage sharing technology has become an important way of information interaction.However,there is a big security problem in the way of information sharing by means of shared links,and the existing cloud storage sharing is to manage all user information in a "mashup" manner with the help of a third-party cloud service provider.In this process,it is difficult to achieve independent sharing of information.Moreover,existing systems require a large amount of communication overhead and high computational cost,and the openness and transparency of the Internet of Things poses a serious threat to the integrity,accuracy,and confidentiality of information.The blockchain provides a decentralized distributed management model.The intelligent contract can replace the third party to realize the autonomous control of information and greatly reduce the communication overhead.The consensus mechanism guarantees the integrity and authenticity of the stored information.This paper focuses on the theoretical research on blockchain technology and cloud storage sharing security model.The specific innovations and research contents are as follows:1)In view of the problem that the existing cloud storage sharing scheme has too high dependence on CSP and low degree of information sharing autonomy,based on proxy re-encryption technology and attribute-based encryption algorithm,a keyword search is proposed.The attribute proxy re-encrypts the ciphertext cloud storage sharing scheme,and proves the feasibility of the scheme through security analysis,algorithm complexity and execution efficiency.2)According to the smart contract working principle in the blockchain,a smart contract for information interaction is designed to replace the CSP of the third party,so that the information sharing parties can communicate spontaneously according to the preset protocol without the participation of the central organization,ensuring the communication.The security of ciphertext conversion and the uninterrupted and efficient information sharing.Based on the working principle of the pool verification pool consensus mechanism,the transmission node is separated from the storage node,and the original information ciphertext is separated from the metadata ciphertext,thereby achieving better anti-collusion attack.In summary,the blockchain attribute proxy re-encryption ciphertext cloud storage sharing system designed in this paper can not only ensure the security and privacy of user information,but also improve the system's execution efficiency and more effectively solve the existing the security problems of the cloud storage sharing system that is more practical.