Public Key Encryption for Cloud Storage Attack using Blockchain

Cloud storage enables user to store data and make it available when it is requested by user. Data generated electronically is very important and it must be encrypted to make sure that the data is tramper-proof. There are two important points to be considered, keyword guessing attack and making cloud storage secure from hackers. In Keyword guessing attack the Keywords search by user are encrypted using secure mechanism and securing the cloud storage means use such techniques which assured to give Confidentiality, Integrity and Accessibility using Blockchain Technology. It is decentralized cloud storage which assist different security mechanisms to protect data. Decentralized cloud storage is itself secure than centralized cloud storage. Because the concept of decentralized is not to store data on single storage device but to store on multiple servers. While storing the data on different location it divided into small parts, and at the time of retrieving data it is available as a complete single block of original data. Whereas in centralized cloud storage data is stored on single storage device. As technology progress the risk from fraudulent users also increases. For this reason, we need some encryption, decryption and authentication mechanism to verify user and if it is authenticated allow access to use its data. There are some techniques also available where user made request on cloud server to receive data which makes cloud server to learn keywords except resulting data. In this paper we make an attempt to review encryption and decryption for cloud storage using blockchain technology to improve security of data.