关键词: 云存储, 数据去重, 存储网关, 侧信道攻击, 所有权证明

Abstract: In a cloud storage system with client-side deduplication, proof of ownership can be used to solve the problem of an adversary getting an entire file via the file hash only. However, schemes based on proof of ownership are vulnerable to side-channel attacks. An adversary can observe the occurrence of deduplication by uploading a file and then infer whether the file exists in the cloud server. An improved proof of ownership deduplication scheme based on storage gateway is proposed. Storage gateway, instead of user, interacts with cloud server, so that the deduplication is transparent to the user. The scheme uses the method of traffic obfuscation to resist side-channel attacks and related-files attack. Analyses and comparisons show that the scheme reduces computation overhead on client-side and improves security.

Key words: cloud storage, data deduplication, storage gateway, side-channel attacks, proof of ownership