Proof of Retrievability and Deduplication in cloud Computing with ResourceConstrained Devices and server

Abstract

Cloud Computing moves the application software and databases to the centralized large data centers,where
the management of the data and services may not be fully trustworthy. In this work, we study the problem of ensuring the
integrity of data storage in Cloud Computing. To reduce the computational cost at user side during the integrity
verification of their data, the notion of public verifiability has been proposed. However, the challenge is that the
computational burden is too huge for the users with resource-constrained devices to compute the public authentication
tags of file blocks. To tackle the challenge, we propose OPoR, a new cloud storage scheme involving a cloud storage
server and a cloud audit server, where the latter is assumed to be semi-honest. In particular, we consider the task of
allowing the cloud audit server, on behalf of the cloud users, to pre-process the data before uploading to the cloud
storage server and later verifying the data integrity. OPoR outsources the heavy computation of the tag generation to the
cloud audit server and eliminates the involvement of user in the auditing and in the preprocessing phases. Furthermore,
we strengthen the Proof of Retrievabiliy (PoR) model to support dynamic data operations, as well as ensure security
against reset attacks launched by the cloud storage server in the upload phase