Towards Practical Protection of Data Access Pattern to Cloud Storage
Qiumao Ma, Wensheng Zhang · 2018
The oblivious RAM model provides a provable approach to protect a client's data access pattern to cloud storage. Most of existing ORAM schemes have communication efficiency as the major optimization priority, but the server-side storage efficiency has been overlooked. Motivated by the observation that, the server-side storage efficiency is as important as communication efficiency when the storage capacity is large or the outsourced data are not frequently accessed, we propose in this paper a new ORAM scheme to address the limitation. Through extensive security analysis and performance comparison, we demonstrate that, the proposed ORAM is secure; also, compared to the state of the art, it significantly improves the server-side storage efficiency and achieves the comparable level of communication efficiency, when consuming the similar amount of client-side storage.