Abstract—To protect outsourced data in cloud storage against corruptions, adding fault

tolerance to cloud storage together with data integrity checking and failure reparation

becomes

critical. Recently, regenerating codes have gained popularity due to their lower repair

bandwidth while providing fault tolerance. Existing remote checking methods for

regenerating-coded data  only provide private auditing, requiring data owners to always stay

online and handle auditing, as well as repairing, which is sometimes impractical. In this

paper, we propose a public auditing scheme for the regenerating-code-based cloud storage.

To solve the regeneration problem of failed authenticators in the absence of data owners, we

introduce a proxy, which is privileged to regenerate the authenticators, into the traditional

public auditing system model. Moreover, we design a novel public verifiable authenticator,

which is generated by a couple of keys and can be regenerated using partial keys. Thus, our

scheme can completely release data owners from online burden. In addition,

we randomize the encode coefficients with a pseudorandom function to preserve data

privacy. Extensive security analysis shows that our scheme is provable secure under random

oracle model and experimental evaluation indicates that our scheme is highly efficient and

can be feasibly integrated into the regeneratingcode- based cloud storage.

Index Terms—Cloud storage, regenerating codes, public audit, privacy preserving,

authenticator regeneration, proxy, privileged, provable secure.

I. INTRODUCTION

CLOUD storage is now gaining popularity because it offers a flexible on-demand data

outsourcing service with appealing benefits: relief of the burden for storage management,

universal data access with location independence, and avoidance of capital expenditure on

hardware, software, and personal maintenances,etc., [1]. Nevertheless, this new

paradigm of data hosting service also brings new security threats toward users data, thus

making individuals or enterprisers still feel hesitant. It is noted that data owners lose

ultimate control over the fate of their outsourced data; thus, the correctness, availability

and integrity of the data are being put at risk. On the one hand, the cloud service is

usually faced with a broad range of internal/external adversaries, who would maliciously

delete or corrupt users’ data; on the other hand, the cloud service

providers may act dishonestly, attempting to hide data loss or corruption and claiming

that the files are still correctly stored in the cloud for reputation or monetary reasons.

Thus it makes great sense for users to implement an efficient protocol to perform

periodical verifications of their outsourced data to ensure that the cloud indeed maintains

their data correctly. Many mechanisms dealing with the integrity of outsourced data

without a local copy have been proposed under different system and security models up to

now. The most significant work among these studies are the PDP (provable data

possession model and POR (proof of retrievability) model, which were originally

proposed for the single-server scenario by Ateniese et al. [2] and Juels et. al. [3],

respectively. Considering that files are usually striped and redundantly stored across

multi-servers or multi-clouds, [4]–[10] explore integrity verification schemes suitable for

such multi-servers or multiclouds setting with different redundancy schemes, such as

replication, erasure codes, and, more recently, regenerating codes. In this paper, we focus

on the integrity verification problem in regenerating-code-based cloud storage, especially

with the functional repair strategy [11]. Similar studies have been performed by Bo Chen

et al. [7] and H. Chen el al. [8] separately and independently. [7] extended the single-

server CPOR scheme(private version in [12]) to the regeneratingcode- scenario; [8]

designed and implemented a data integrity protection(DIP) scheme for FMSR [13]-based

cloud storage and the scheme is adapted to the thin-cloud setting1. However, both of them

are designed for private audit, only the data owner is allowed to verify the integrity and

repair the faulty servers. Considering the large size of the outsourced data and the user’s

constrained resource capability, the tasks of auditing and reparation in the cloud can be

formidable and expensive for the users [14]. The overhead of using cloud storage should

be minimized as much as possible such that a user does not need to perform too many

operations to their outsourced data (in additional to retrieving it) [15]. In particular, users

may not want to go through the complexity in verifying and reparation. The auditing

schemes in [7], [8] imply the problem that users need to always stay online, which may

impede its adoption in practice, especially for long-term archival storage.

1. Problem Statement:

Since cloud service providers (CSP) are separate administrative entities, data outsourcing is actually relinquishing user’s ultimate control over the fate of their data. As a result, the correctness of the data in the cloud is being put at risk due to the following reasons. As users no longer physically possess the storage of their data, traditional cryptographic primitives for the purpose of data security protection can not be directly adopted. Thus, how to efficiently verify the correctness of outsourced cloud data without the local copy of data files becomes a big challenge for data storage security in Cloud Computing. Note that simply downloading the data for its integrity verification is not a practical solution due to the expensiveness in I/O cost and transmitting the file across the network. Besides, it is often insufficient to detect the data corruption when accessing the data, as it might be too late for recover the data loss or damage.

Objective

1. To motivate the public auditing system of data storage security in Cloud Computing and to provide a privacy-preserving auditing protocol, i.e., our scheme will support an external auditor to audit user’s outsourced data in the cloud without learning knowledge on the data content.

2. To the best of our knowledge, our scheme will be the first to support scalable and efficient public auditing in the Cloud Computing. In particular, our scheme will achieve batch auditing where multiple delegated auditing tasks from different users can be performed simultaneously by the TPA.

3. To prove the security and justify the performance of our proposed schemes through concrete experiments and comparisons with the state-of-the-art.

Consider a cloud storage system in which there are a client and an untrusted server. The

client stores their 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.

Advantages

Proposed system has the following main contributions:

Remote data integrity checking protocol for cloud storage. The proposed system

inherits the support of data dynamics, and supports public verifiability and

privacy against third-party verifiers, while at the same time it doesn’t need to use

a third-party auditor.

Security analysis of the proposed system, which shows that it is secure against the

untrusted server and private against third party verifiers.

The TPA doesn’t even allows the CSP to read the data of the user.

When anyone tries to modify or steal the data TPA informs the user by verifying the data.

The TPA allows the user to know the information about the data stored in the cloud.

In the proposed system, we use the technique of providing more security by using the Third Party Auditor (TPA) .

Module:

Admin module:

Admin is allowed to check which user registered and which data is stored in the cloud space area.

TPA Module:

TPA check that data is modified or not if modified that information send to user.

User Module:

User can register and he can login with his user id and password and he can upload the data to cloud space area.

Block Verification Module:

User can check that the uploaded file is modified by any one or not (like server area).

Block Insertion Module:

In the block insertion module user can insert the new block.

Block Deletion Module:

In the Block Deletion Module user can delete the block.

2. Requirements:

5.1 HARDWARE REQUIREMENTS:

1. Processor Pentium-III or higher

2. Processor Speed 1.1 Ghz

3. Hard Disk Space 20 GB (min.) 4. Ram Memory 256 MB (min.)

5.2 SOFTWARE REQUIREMENTS:

1. Operating System Windows 7or higher 2. Application Server : IIS3. Database: MSSQL SERVER 2008 or higher4. Databse Connectivity: ADO5. Front end : C#/ASP.NET

5.3 TOOLS/PLATFORM:

This project is proposed to develop using the Internet Tools, which are most suited for development of the system. These tools are as follows: -

1. HTML2. Java Server Pages3. Cascading Style Sheets (CSS)

References:.[1] ch. mutyalanna,p. srinivasulu,m. kiran,"dynamic audit service outsourcing for data integrity in clouds"issn: 2278 – 1323,volume 2 issue 8, august 2013

[2] Sajeev V,Gowthamani R,"Privacy Preserving Public Auditing in Secured Cloud Storage Using Block Authentication Code",ISSN Vol.2, Special Issue 1, March 2014

[3] qian wang, student member, ieee, cong wang, student member, ieee, kui ren, member, ieee, wenjing lou, senior member, ieee, and jin li"enabling public auditability and data dynamics for storage security in cloud computing"ieee transactions on parallel and distributed systems, vol. 22, no. 5, may 2011

[4] Miss. Nupoor M. Yawale Prof. V. B. Gadichha "Third Party Auditing (TPA) for Data Storage Security in Cloud with RC5 Algorithm" Volume 3, Issue 11, November 2013 ISSN: 2277 128X Miss. Nupoor M. Yawale Prof. V. B. Gadichha

[5] ch. mutyalanna,p. srinivasulu,m. kiran,"dynamic audit service outsourcing for data integrity in clouds"issn: 2278 – 1323,volume 2 issue 8, august 2013

[6] Sajeev V,Gowthamani R,"Privacy Preserving Public Auditing in Secured Cloud Storage Using Block Authentication Code",ISSN Vol.2, Special Issue 1, March 2014

Feature in above project:

Here we are using concept of cloud replica .In amazon or

google drive we are storing data on server and amazon or

google create 3 replica on three different server hear ,this

part we are using in our project for corrupted file recovery

system. In existing system TPA only inform file is change or

modified. now in this paper we are giving extra facility to

user can recover the file with help of TPA and user

authentication process. For accessing(recovering) the server

file both TPA and User Should be authenticate. File not access

or recover by single user either TPA or User.

Algorithm :

For data Integrity : MD5

For Security:we use AES,Cipher,RSA,DES these Random encryption

cloud used for security .