International Journal For Recent Development In Science And Technology

Mobile cloud storage (MCS) provides a convenient way for clients to store data in the cloud.In this paper, we present an efficient, secure, and privacy-preserving MCS solution that ensures both data confidentiality and privacy, with a particular focus on protecting access patterns.At the heart of our approach is the Oblivious Selection and Update (OSU) protocol.This protocol uses onion additively homomorphic encryption with fixed encryption layers, allowing the client to retrieve an encrypted data item from the cloud and update it with a new value.The process generates a small encrypted vector, which significantly reduces both the client's computational load and communication costs.Compared to existing methods, our scheme offers several benefits, such as fine-grained data structures with smaller item sizes, minimal computational effort on the client side (requiring only a few homomorphic operations), and constant communication overhead, making it well-suited for MCS applications.Furthermore, by utilizing the "verification chunks" technique, our scheme provides verifiability to prevent malicious behavior from the cloud.Our experimental results demonstrate that our solution is more efficient than previous oblivious storage methods in terms of both client and cloud workloads.