Data Confidentiality and Integrity Preserving Outsourcing Algorithm for System of Linear Equation to a Malicious Cloud Server

Abstract

Cloud computing has become a revolution in the field of computing, which enables flexible, on-demand, usage of computing resources in pay-as-per-use model. However, data and computation go to some third-party cloud server beyond the physical control of client escalates various privacy and security concern. This paper proposes an improved outsourcing algorithm for system of linear equation (SLE). The improvements are first, the existing work uses expensive cryptographic computation such as Paillier encryption for security arrangement, the proposed solution does not use such cryptographic primitives rather uses efficient linear transformation method. Secondly, the previous work uses an iterative process, which required 𝐿 rounds of communication between the client and cloud server, at the same time each iteration causes burden of a decryption followed by a matrix vector multiplication. However, the proposed solution required an optimal one round of communication and one-time transformation and retransformation service. Third, the previous work gives result verification method with (1/2l) error probability, the value of 𝑙 is a trade-off between security and efficiency. However, the proposed solution gives an error checking with an optimal probability of one. Moreover, a security analysis has been performed on the previous method, which proves marginal security arrangement due to inappropriate use of the Paillier encryption scheme. The proposal has been verified through theoretical and experimental analysis, which demonstrate the superiority of the proposed algorithm as compared to the existing algorithm.