Improving Cloud Security and Privacy Using Blockchain

In recent years, securely sharing personal information between two parties involves high risk. Most of the medical health records and financial transactions includes huge uncertainty while storing and retrieving from cloud for query processing. Blockchain is an open platform where each transaction is tampered proof. Various methods like zero knowledge proof or hashing methods used to hide the sensitive information from the real world. When associating blockchain with cloud this uncertainty is reduced. The user information is segregated into two categories sensitive and non-sensitive using linear regression method before processing in cloud. To improve security and increase privacy from various attacks, the sensitive part of data is encrypted using ECC and non- sensitive part of data is encrypted using RSA algorithm. Using Ethereum blockchain the policy of the user is verified and query processing is done. The performance of the model is compared with the existing techniques and results are evaluated using the classification error rate and performance of security against manual attacks.