DECENTRALIZED CLOUD STORAGE USING BLOCKCHAIN

ABSTRACT:-

            Cloud storage is one of the leading options where you can keep big data, however, a way to keep a single cloud space using a computer is not secure. On the other hand, Blockchain is a cloud-based storage system that ensures data security. Any computer node connected to the Internet can join and build peer networks thus increasing utilization of resources. Blockchain is a peer-to-peer system distributed per node on the network that keeps a copy of the blockchain thus making it invariant. In the proposed system, the user file is encrypted and stored on multiple peers in the network using IPFS (Inter Planetary File System) protocol. IPFS creates hash values. The hash value indicates the path of the file and is stored in the blockchain. In this project we use the blockchain and ipfs cloud platform for storing the file of n users. Once the user uploads any file it will get encrypted and that file stored on ipfs and file metadata will be stored on blockchain. And at the time of downloading the particular file, the metadata of that file will be retrieved from the blockchain and the file will be decrypted and displayed to you. Smart contracts are used to store file details in the blockchain and also transfer the cryptocurrency (ETH) from the user’s wallet to the peer’s wallet. AES encryption algorithm for enhancing the security of user’s data stored in cloud storage. This paper focuses on secure data shared across the country storage, high availability of data, and efficient use of storage facilities. 

OBJECTIVES OF THE PROJECT:-

The main objectives of this system are:

• Our main motive is to store the users file securely using blockchain network and ipfs platform.
• Our goal is to build a system to access users files easily among blockchain clouds without relying on a centralized supervisory system.
• The main goal of this work is to develop an understanding of the scenarios that involve deploying hybrid cloud, the benefits that arise from this incorporation and the challenges in such a context.

EXISTING SYSTEM:-

Blockchain networks can be used for two purposes. The integrity of the hash data collected from cloud collection to the block chain network is protected and stored in a distributed manner to ensure stability. In addition, each response from the cloud server and website access will be recorded in a block series for further review or investigation. Not only will the data record be kept permanently, but also, a data block will be generated to validate the data. The cloud server processes data from cloud collections and data access records, which are the same function as block chain networks. 

To secure the data record, the cloud server is obliged to request block data from the block chain network as permanent proof of data integrity. Additionally, data analytics data analysis and control system and server analysis can help determine the first stage of denying a distribution of service attacks. block chain network data and block production. Cloud data validation, auditing and decision making. The main steps are as follows: Business ID registration. In this program, we first register the ID number of each business in the cloud collection to identify collected data. After registering, start collecting data, which is the log file generated to schedule cloud work in the collection. We treat each log as an object and speed up individual data to improve efficiency before uploading to a block chain network. Raw data is also stored on a cloud website for future reference. Data transfer and commands. 

Each data collected from the cloud collection is structured as a meta-ancestor time data. After sending a meta-ancestor to the control system, the control system transfers hash data to the block chain network and sends the original data to the cloud database. At the same time, the control system will revert back to the cloud collection of some command data, these commands will also be converted to time, command format, recorded in the block chain.

PROPOSED SYSTEM:-

The user first creates an account on the metamask. The user’s account address and wallet balance are fetched in the app through web3.js from the metamask. Users select the file to upload through file picker. System checks for the number of available peers. Further, the AES algorithm uses the user’s wallet address as a key and encrypts the uploaded file. A payment dialogue seeks for the user’s confirmation. On confirming the payment, the user’s file is stored across available peers using IPFS protocol. IPFS then returns a hash value consisting of the path of the file. This path is then mapped with the user’s address using a smart contract and gets stored securely in the blockchain. To achieve high availability and reliability of data, the uploaded data is replicated on three peers. For better performance the system blacklists peers every time they are unavailable for data retrieval. The terminology is briefly discussed below.

 Metamask : Browser extension which acts as a bridge to connect with the ethereum network.

 Ethereum network : It is an open-source, public blockchain- based distributed computing platform. Ethereum uses smart contracts where one can add business logic to make decentralized applications as per the business requirements. Peers: These are the users of the system who have pledged to rent their free storage for an other user’s to store files. 

AES: Advanced Encryption Standard (AES) is a symmetric- key algorithm that supports block length of 128 bit and can have a key size of 128, 192, and 256 bits. 

IPFS protocol: IPFS is an open-source peer to peer file transfer protocol.

1. Uploading of file User uploads file using the file picker. The system checks the file size and ensures storage availability in the network. The file is uploaded when enough storage is available.

 B.Users are notified to try again when enough storage is unavailable. B. Encryption of file The uploaded file is encrypted using AES 256 bit algorithm. The encryption key is generated using the user’s wallet address and randomly generated salt value. This encryption key along with an IV is used to encrypt the user’s data. This maintains the confidentiality of the user’s data.

1. Storing a file across multiple peers The encrypted file is then divided into blocks of 64KB and sent to different peers across the network with the help of the IPFS protocol. The proposed system uses a private IPFS network to allow registered peers to store the file in the network. The file block is replicated on multiple peer’s storages for high availability using the IPFS cluster.  
2. Storing a file across multiple peers IPFS returns a hash value which indicates the path of the file. The hash value along with metadata is mapped with the user’s wallet address and is stored in the blockchain using a smart contract. Smart contracts are like agreements and are used to eradicate the need for a third party. They control the transaction between nodes or assets between parties under certain conditions. This is lines of code stored on a blockchain network and are automatically executed when predetermined terms and conditions are met.

MODULES:

• User Registration: User have to register to become a part of this cloud system.
• User Login: User have to login himself to add/view all files.
• Home page: User can view their own file which he/she recently added and also he/she has access to download it. And also he/she can share that file to any user.
• Add file: User can add their own file on cloud system.
• Received files: User can view file which shared by the other user to him and it will ask the key while downloading which shared on user mail id.

ADVANTAGES:-

• A hybrid cloud gives businesses the flexibility to adopt the most appropriate and innovative solution for the organization and choose from a range of management and service models from multiple vendors, preventing vendor lock-in.
• Many organizations have moved to the hybrid cloud for greater scalability. A hybrid cloud environment allows organizations to scale resources and optimize performance based on the organization’s changing needs.
• Time-to-market can be the defining factor in an organization’s competitive edge. The hybrid cloud helps organizations optimize IT performance to speed up the time to deliver products and services to customers. 
• In this digital era, businesses need the ability to adapt and change direction quickly. Using the hybrid cloud model, organizations can connect existing technology and on-prem infrastructure to cloud resources for added agility.

HARDWARE AND SOFTWARE REQUIREMENTS:-

HARDWARE:-

• Processor: Intel Core i3 or more.
• RAM: 4GB or more.
• Hard disk: 250 GB or more.

SOFTWARE:-

• Operating System : Windows 10, 7, 8.
• Python 
• Anaconda
• Spyder, Jupyter notebook, Flask.
• MYSQL