Supporting dynamic update scheme for assured deletion based-multi-copy association tree

Cloud storage services provide resources for resource-constrained users, which reduces their local overhead and computing cost. As an extension of cloud computing, fog introduces a layer between the users to deploy storage, other types equipment, allowing operate outsourced data conveniently. Although brings many conveniences assured deletion is still one crucial security challenges. This paper proposes efficient secure scheme (SDUS-AD) that supports dynamic updates in multi-copy scenarios. In this scheme, new structure called Multi-Copy Association Tree designed realize update efficiently safely. A cloud-fog-user used meet needs ensure confidentiality privacy. Detailed performance analysis simulation experiments show SDUS-AD efficient, safe, feasible.