CIDER: A Low Overhead Approach to Privacy Aware Client-side Deduplication

摘要

In cloud storage systems, malicious users may exploit client-side deduplication responses to infer what other users are storing in the cloud. We propose CIDER, a low overhead approach to mitigate this side channel by obfuscating the existence status of data stored in the cloud. We analyze the scheme's ability to obfuscate the side-channel and discuss attacks that a user may still employ and what he could learn from such attacks. Finally, we use simulated and real data to examine the performance under realistic deduplication workloads, revealing that CIDER ends up transmitting less redundant information than similar methods, thus enabling a more efficient utilization of the available bandwidth.