Design And Implementation For The File Encryption Distributed Stroage System Based On Blockchain Network

With the rapid development of Internet technology,any operation by individuals or institutions on the computer network will produce data.However,not all data can be safely disposed to all users on the Internet.That is,these data may contain many important and sensitive privacy information,such as personal identity information,medical treatment information,password information,etc.Currently,these data are mainly stored on the Internet in the form of files and are saved on storage media not owned by the data owner,which to a large extent poses a security risk of data leakage.For example,personal information,case information,and even radiographic images entered by patients in hospitals are all personal privacy data,but most hospitals currently use traditional databases or PACS(Picture Archiving and Communication System)as the storage medium for the above information,which to a certain extent weakens the patient’s management rights over personal data.In addition,because the actual data users do not understand or have no right to use the storage device,the actual possessors of the authority to read or even tamper with these data are often the medium providers or backend operation and maintenance personnel.In similar scenarios,in other environments involving distributed multi-party cooperation but centralized data storage-such as customs,ports,railways,etc.,the internal data of each participant is often stored in the data center of their own enterprise,and it is impossible to truly achieve management and authorization of privacy data.To solve the above problems,this paper designs a file encryption and distributed storage system based on blockchain.This system serves as a multi-level point-to-point communication and storage network,distributing user data to participants in the network.A blockchain system is built on the upper layer of the network,writing various operation scenarios of files and encrypted file metadata into blocks,realizing secure access to user data and immutability.The construction of this system requires solving the following technical problems.This paper designs and implements the corresponding key technologies to solve the corresponding technical problems:(1)The system should have the ability to prevent data tampering.This paper solves this problem based on the decentralized distributed encryption technology of blockchain,through encryption algorithms,consensus algorithms and other mechanisms.(2)In the scenario where many participants communicate,reducing communication complexity is a great challenge.This paper uses point-to-point communication technology based on distributed hash rings to achieve logarithmic complexity multi-party communication,ensuring that the communication network supports many participants.(3)In terms of data storage,to achieve distributed redundant storage of data,this paper uses the AONT(All-Or-Nothing Transform)encryption algorithm to implement redundant encryption slicing of data,ensuring that users can recover plaintext data without obtaining all slices after obtaining a certain number of slices.After the slicing is completed,it is distributed to various nodes in the network through the distributed hash ring network,and the blockchain system running on the node is used for consensus recording to ensure that the data is safe and cannot be tampered with.After solving the above technical problems,this paper constructs a file encryption and distributed storage system,realizing functions such as file upload,authorization,and reception of different role participants.This system has a complete logical closed loop.Therefore,in the above multiparty cooperation scenarios,the data management rights are returned to the data owners,ensuring the security,integrity,and traceability of the data,At last,the effectiveness of the system is verified through a series of functional and performance tests.