26-05-2012, 04:41 PM
A Privacy-Preserving Remote Data Integrity Checking Protocol with Data Dynamics and Public Verifiability
A Privacy-Preserving Remote Data Integrity Checking.pdf (Size: 183.91 KB / Downloads: 30)
INTRODUCTION
Storing data in the cloud has become a trend [2]. An
increasing number of clients store their important data in
remote servers in the cloud, without leaving a copy in
their local computers. Sometimes the data stored in the
cloud is so important that the clients must ensure it is
not lost or corrupted. While it is easy to check data integrity
after completely downloading the data to be checked,
downloading large amounts of data just for checking data
integrity is a waste of communication bandwidth. Hence, a
lot of works [1], [3], [4], [5], [6], [7], [8], [9] have been
done on designing remote data integrity checking protocols,
which allow data integrity to be checked without completely
downloading the data.
TECHNICAL PRELIMINARIES
We consider a cloud storage system in which there are
a client and an untrusted server. The client stores her data
in the server without keeping a local copy. Hence, it is of
critical importance that the client should be able to verify
the integrity of the data stored in the remote untrusted
server. If the server modifies any part of the client’s data,
the client should be able to detect it; furthermore, any third
party verifier should also be able to detect it. In case a third
party verifier verifies the integrity of the client’s data, the
data should be kept private against the third party verifier.
Below we present a formal statement of the problem.
DATA DYNAMICS
The proposed protocol supports data dynamics at the
block level in the same way as [1]. In the following we
show how our protocol supports block modification. Due to
space limitation, we describe the support of block insertion
and block deletion in the full version [20].
CONCLUSIONS AND FUTURE WORK
In this paper we propose a new remote data integrity
checking protocol for cloud storage. The proposed protocol
is suitable for providing integrity protection of customers’
important data. The proposed protocol supports data insertion,
modification and deletion at the block level, and
also supports public verifiability. The proposed protocol
is proved to be secure against an untrusted server. It is
also private against third party verifiers. Both theoretical
analysis and experimental results demonstrate that the proposed
protocol has very good efficiency in the aspects of
communication, computation and storage costs.