ase-PoW: A proof of ownership mechanism for cloud deduplication in hierarchical environments

Abstract

Proof-of-Ownership (PoW) can be an effective deduplication technique to reduce storage requirements, by providing cloud storage servers the capability to guarantee that clients only upload and download files that they are in possession of. In this paper, we propose an attribute symmetric encryption PoW scheme (ase-PoW) for hierarchical environments such as corporations, in which (1) the external cloud service provider is honest-but-curious and (2) there is a flexible access control in place to ensure only users with the right privilege can access sensitive files. This is, to the best of our knowledge, the first such scheme and it is built upon the ce-PoW scheme of González-Manzano and Orfila (2015). ase-PoW outperforms ce-PoW in thaact it does not suffer from content-guessing attacks, it reduces client storage needs and computational workload.