Mixed Homomorphic Encryption with Byte Level Automorphism for Dynamic Data Operations in Cloud Computing

Abstract

Cloud Computing has been envisioned as the next generation architecture of IT enterprise. newlineIn contrast to the traditional solutions where the solutions are under physical, logical and newlinepersonnel controls, cloud computing moves the application of softwares and databases to newlinethe large data centers where the management of data and the services may not be fully newlinetrustworthy. The focus of this proposal is to ensure cloud data storage security which has newlinealways been an important aspect. newlineThe proposal aims to provide a secure and efficient storage structure with dynamic data newlineoperations support. The proposed method has been developed using homomorphic newlineencryption techniques in particular fully homomorphic method. The presented work has newlineused an improvised version of key switching matrices for homomorphic operations. The newlineclient encrypts the data and stores the encrypted data in the server. Whenever there is a newlineneed for computation only the request is sent to the server. The server does the operation newlineon the encrypted data and the result is sent to the client. The client can then verify the newlineresult with the help of metadata. The encryption is carried out byte level and hence the newlinename byte level automorphism. newlineThe presented work is studied with two types of files, text files and image files. For the newlinetext files, data operations like insert, delete and update operations are applied and the newlineimage files are tested with the operations like addition and resizing. The results obtained newlineare compared with the existing works with different file size and block size and newlineobservations are made. newlineStrong key protection is ensured for every byte of data with the help of computation of key newlineswitching matrices. As the key switching matrices are long in nature, this guarantees newlineprotection for both secret key and public key and enables secured distribution of data newlineacross storage servers. In the proposed work, every source file contains N blocks each of newlinesize N bytes and for each block Encrypted Data Block (EDB) is generated. This makes newline