Enabling Secure Data Sharing Scheme in the Cloud Storage Groups

International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
Volume: 04 Issue: 07 | July -2017 www.irjet.net p-ISSN: 2395-0072
© 2017, IRJET | Impact Factor value: 5.181 | ISO 9001:2008 Certified Journal | Page 2491
Enabling Secure Data Sharing Scheme in the Cloud Storage Groups
C.Pavani1, S.Vasundra2
1M.Tech, CSE Department, JNTUCEA, Ananthapuramu, AP, India.
2Professor, CSE Department, JNTUCEA, Ananthapuramu, AP, India.
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Abstract--In cloud computing, cloud service providers
offer an abstraction of infinite storage space for clients to
host the data. It helps clients to reduce economic overhead
of data management by moving the local management
system into cloud servers. However, security concern
becomes the main constraint. To preserve data
confidentiality, there is an approach to encrypt data files
before the client upload the encrypted data into the cloud
which is challenging task in active groups in the cloud.
This paper proposes an Identity based ring signature for
data sharing in the cloud storage groups. This system aims
at offering forward security to massive amount of data
sharing in the cloud. It also provides the authenticity and
anonymity of the end users. The method can achieve
secure key distribution, fine-grained access control, anti-
collusion attack and secure user revocation.
Keywords: Access control, privacy-preserving, key
distribution, cloud computing, identity based ring
signature.
1. INTRODUCTION
Now-a-days the internet has to support different
technologies. One of the mainly popular technology is
cloud computing. Cloud computing atmosphere provides
the massive storages facility to the client. Now a days,
cloud computing is a technology to allow the user
accessing the data which stored in remote server. It can
be easily and quickly accessible through the internet
which has been pay per use on demand service. Cloud
computing mainly used for business and organization
and provide the huge amount of space for data sharing at
low cost. Clouds are provided by many cloud computing
service providers like Amazon, Drop box, Google app
engine etc. Cloud provides one of the most essential
services is data storage.
Data sharing between two members or group of
members take several issues into account. They are
efficiency, data integrity and privacy of data owner.
Providing the privacy and the integrity are the most
challenging tasks for dynamic groups.
The existing system provides a secure data sharing
scheme for dynamic members [1]. Without using Secure
Communication channels, this method uses key
distribution in secure way such that group manager
provides private keys to the users. The scheme can
achieve fine-grained access control. It provides the
security against collusion attack by using group
signature which provides secure user revocation.
Collusion attack means decryption of data by revoked
user using his secret key and get secrete file by conspire
with the cloud. Secure user revocation means the
revoked users cannot get the original data file even if
they conspire with the untrusted cloud. The scheme can
achieve fine efficiency, which means previous users need
not to update their private keys when either a new user
joins in the group or a user is revoked from the group.
Secure and efficient methods are needed to ensure
integrity and privacy of data stored at the cloud [2].
Group signature [3] allows members of a specified group
to sign message on behalf of the entire group that is
without revealing their individual identities. Group
signature has two properties 1) anonymity 2)
traceability. Anonymity means that, it does not revel
which specific group members form the signature. As in
any privacy preserving applications, anonymity of the
users is maintained as much as possible, but still need to
be sure that there is a mechanism in place for
misbehaving members of group to get caught. The group
signature identifies the misbehaving users can be easily
revealed with help of traceability property. But there are
some security applications in which it’s disagreeable for
a signer identity to be revealed. It is violating the
anonymity property of group signature. To overcome
this drawback, this paper proposes the Identity Based
Ring Signature [4]. This system aims at offering forward
security to massive scale data sharing in the cloud.
Ring signature for data sharing inside the cloud provides
secure data sharing using identity based ring signature
within the group. It additionally provides the
authenticity and anonymity of the end users. The
proposed system avoids costly certificate keys for
verification as in the conventional public key
infrastructure setting which is a bottleneck. In Identity
based ring signature, Leakage of secret key of any user
doesn’t make all preceding generated signatures invalid.
The assets is especially important to any huge amount of
data sharing system, as it is impossible to ask all data
owners to re-authenticate their data even if a secret key
of one single user has been revealed.

The remaining of the paper is organized as follows.
In the section 2, related works are discussed. The
proposed system is presented in detail in section 3
followed by results in section 4. Finally the conclusion is
made in section 5.
2. RELATED WORK
Liu et al. [5] proposed a secure multi-owner data sharing
scheme, named Mona. This scheme can attain fine-
grained access control and revoke users will not be able
to access the sharing data again once they are revoked.
However, the scheme will easily suffer from the collusion
attack by the revoked user and the cloud [6]. The
revoked user can use his personal key to decrypt the
encrypted data and get the secret data after his
revocation through conspiring with the cloud. In the
phase of document access, the revoked user sends his
request to the cloud, and then the cloud responds the
corresponding encrypted records file. After that, the
revoked user can compute the decryption key with the
help of the attack algorithm. At last, this attack can cause
the revoked users getting the sharing data and disclosing
other secrets of legitimate members.
Zhou et al. [7] proposed a secure access control scheme
on encrypted data in cloud storage space by invoking
role-based encryption technique. This method can
achieve well-organized user revocation that combines
role-based access control policies with encryption to
secure huge data storage space in the cloud.
Unfortunately, the verifications between entities are not
afraid. The method easily suffers from attacks, for
example, collusion attack. At last, this attack can direct to
disclosing sensitive data files.
Zou et al. [8] proposed a realistic and flexible key
management system for trustworthy collaborative
computing. It is designed to achieve efficient access
control for dynamic groups. Regrettably, the secure
approach for sharing the personal permanent portable
secret between the member and the server is not
supported and the secret key will be disclosed once the
personal permanent manageable secret is obtained by
the attackers.
Nabeel et al. [9] proposed a privacy preserve procedure
based data sharing scheme in public clouds. But, this
scheme is not secure for the reason that of the weak
protection of commitment in the phase of identity token
issuance.
3. PROPOSED METHOD
In order to achieve better security by providing fine
grained access control and reducing key generation
overhead, Identity Based Ring Signature proposed. Ring
signature is group oriented signature with privacy
concerns [10]. It is one of the digital signatures. This
method provides the authenticity and anonymity of the
end user. As opposed to conventional approaches
Identity based ring signature doesn’t allow certificate
verification. Identity based ring signature combines the
identity based cryptosystem and ring signature.
The ring signature scheme consists of three algorithms:
KeyGen, Sign and Verify. Each user will run KeyGen
individually in this algorithm, on input the security
parameter 1k, will output a key pair (pk, sk). The Sign
algorithm, on input takes a secret key sk, a ring R
contains list of public keys belonging to members of ring,
a signature θ and a message m, the output is a signature
σ on m. Finally, the Verify algorithm, on input takes the
ring R, a signature σ, and a message m, then the output is
1 if some member of R created the signature σ on m and
otherwise the output is 0.
Framework
An ID-based ring signature scheme consists of the
following four algorithms: Setup, KeyGen, Sign, and
Verify.
Setup: Taking a unary input string 1k where k is a
security parameter, it produces the master secret key s
and the common public parameters params, which
include a description of a finite signature space and a
description of a finite message space.
KeyGen: It returns Signer’s secret key SID by taking the
input of the signer’s identity ID ∈ {0,1}∗ and the master
secret key s. (The corresponding public verification key
QID can be computed easily by everyone.)
Sign: On input of a message m, a group of n users’
identities S{IDi}, where 1 ≤ i ≤ n, and the secret keys of
one members SIDs, where 1 ≤ s ≤ n; it outputs an ID-
based ring signature σ on the message m.
Verify: It take input as ring signature σ, a message m
and the group of signers’ identities S{IDi}, it outputs 1 for
“true” or 0 for “false”, depending on whether σ is a valid
signature signed by a certain member in the group S{IDi}
on a message m. These algorithms must satisfy the
standard consistency constraint of ID- based ring
signature scheme, i.e. if σ = Sign(m,S{IDi},SIDs), and IDs
∈ S{IDi}, we must have Verify(σ,S{IDi},m) = 1 and
otherwise output is 0.

A secure ID-based ring signature scheme should be
enforceability and signer-ambiguous.
Figure 1: Architecture of cloud data Sharing Scheme
The system model consists of 3 different entities: 1.The
cloud server, 2. A Group Admin (i.e., group manager) and
3.A set of group members.
Cloud Server: Cloud is the huge storage of resources.
Cloud is responsible for storing all members of data and
access to the file within a group to other group members
based on publically offered revocation list which is
maintained by Group Admin. We imagine that the cloud
server is honest but curious. That is, the cloud server will
not unkindly delete or alter user data, due to the security
of data auditing schemes
Group Admin: The Group Admin is acted by the
administrator of the company. Therefore we imagine
that the Group Admin is fully trusted by the other
parties. Group Admin perform various operations such
as system parameters generation, user registration,
group creation, assign ring signature, generation of
private key using bilinear mapping and assign to the
requested user, maintain revocation list and migrate this
list into cloud for public use, and traceability.
Group Members: Group members are a set of registered
users that will store their private data into the cloud
server and share them with others in the group. Both
Group Admin and group member can login using their
login details. After successful login, Group Admin
activates newly added users of the cloud by generating
keys for each member using bilinear mapping and send
it to the corresponding group members. He can also
check the group details, and assign group signature.
After successful login, Group Members signature is
verified. After successful verification, the member can
upload, download and can modify the files. Group
member must be encrypting data file before uploading to
the cloud. The Group Members account can be revoked
after he leaves the cloud by the Group Admin.
User Registration: After successful creation of cloud
setup, members want to get registered with the system
through user registration process. While registering,
members have to submit their personal details for
completion of registration process. User registered with
their information such as identity (user name, mobile no
and email-id). During registration process, user got
unique identity and access structure. This generates
secret key for the members. For registered users they
will obtain private key, that secret key is used for file
encryption and decryption.
User Authentication: The user can login successfully
only if user id and password are entered correctly. The
login is a failure if the incorrect user id or wrong
password is enters by the user. This helps in preventing
unauthorized access.
Key Distribution: Means of distribute secret keys
through the Group Admin that is valid only if the group
members are not revoked from the group. Key can be
updated by generating new key from an old key.
User Revocation: User revocation is the method of
removal of user from system user list which is
performed by group admin. Group admin can directly
revoke multiple users through public revocation list at
every time without affecting any non revoked user. If the
login credentials of the specified user matches with the
details of revocation list then access denied.
File Upload: File upload is the method of storing
specified data files into the cloud. Uploaded files remains
in the cloud up to the time specified while uploading the
file. Before uploading the file, file has to be encrypted
and compacted to ensure security and privacy of the
files. Then it is encapsulated with corresponding
decryption key and time to live (TTL) value for the file
and send it to cloud.
File Download: To access the data that are store in the
cloud, group member will give request as group id, data
id. Cloud server will verify their signature, if the group
member in the same group then allow to access file.
Group member have rights to access data, but not having
rights to delete or alter the data that are store in the
cloud.

4. RESULTS
Security Analysis
Table 1: Security performance comparison
RBAC Mona Proposed
method
Secure key
distribution
 
Access control   
Secure user
revocation

Anti-collusion
attack

Data
confidentiality
 
As compared with RBCA and Mona the proposed scheme
can achieve secure key distribution, fine-grained access
control, protection from collusion attack, data
confidentiality and secure user revocation.
Performance Analysis
With the aid of identity based ring signature, on the basis
of the total time consumed to upload and download a file
to/from the cloud. The total time is composed of the time
from the time of submission of ask for to the cloud
server to the point of time at which the file is
uploaded/downloaded to/from the cloud.
Table 2: Comparison of Turnaround Time
File
size
(KB)
Existing
Method
Proposed
method
Upload Down-
load
Upload Down-
Load
150 12.5 11.6 12 7.8
500 35 40.5 33.8 32.3
1000 80.5 85.6 77.4 50.8
1500 95.1 122.2 82.1 51.9
Table 2 shows that turnaround time for upload and
download the file. In general, the time to upload and
download the data increased with the increase in the file
size This table reveal that the proposed method
outperforms the existing method appropriate to the
absence of heavy computations and memory overhead.
Figure 2: Performance of File Upload
In Figure 2 shows the result for upload time. X axis
represents the file size Y axis represents the time. In
existing system method 1.5mb was uploaded in 95.1s,
where as in proposed system method it takes 82.1s to
upload a 1.5mb file. This graph clearly shows that as
compare to the existing system the performance of
proposed system is higher.
Figure 3: Performance of File Download.
In Figure 3 shows the result for download time. X axis
represents the file size Y axis represents the time. In
existing system method 1.5mb was downloaded in
122.2s, where as in proposed system method it takes
51.9s to upload a 1.5mb file. This graph clearly shows
that as compare to the existing system the performance
of proposed system is higher.
5. CONCLUSION
This paper introduces Identity Based Ring Signature, to
provide the security for large amounts of data sharing in
the cloud by using identity based ring signature. Ring
signature is group oriented signature with privacy
concerns. It is a type of digital signature. This method
provides the authenticity and anonymity of the end user.
Identity based ring signature reduces the process of
official document verification, which is a bottleneck

problem in conventional public key infrastructure.
Proposed system supports multiple users to distribute
common data across the members and each member can
involve in data dynamics.
6. REFERENCES
1. Zhu, Z., & Jiang, R. (2016). “A secure anti-
collusion data sharing scheme for dynamic
groups in the cloud”. IEEE Transactions on
parallel and distributed systems.
2. S. Vasundra (2016) “Efficient & Secure Privacy
Preserving Public Auditing Scheme for Cloud
Storage”, ISSN- 2278-1323, Vol 5, Issue 9.
3. Camenisch, J., & Michels, M. (1998, October). A
group signature scheme with improved
efficiency. In Asiacrypt (Vol. 98, pp. 160-174).
4. Chow, S. S., Yiu, S. M., & Hui, L. C. (2005, June).
Efficient identity based ring signature.
In International Conference on Applied
Cryptography and Network Security (pp. 499-
512). Springer, Berlin, Heidelberg.
5. Zhu, Z., Jiang, Z., & Jiang, R. (2013, December).
The attack on mona: Secure multi-owner data
sharing for dynamic groups in the cloud.
In Information Science and Cloud Computing
Companion (ISCC-C), 2013 International
Conference on (pp. 213-218). IEEE.
6. Liu, X., Zhang, Y., Wang, B., & Yan, J. (2013).
Mona: Secure multi-owner data sharing for
dynamic groups in the cloud. ieee transactions
on parallel and distributed systems, 24(6).
7. Zhou, L., Varadharajan, V., & Hitchens, M. (2013).
Achieving secure role-based access control on
encrypted data in cloud storage. IEEE
transactions on information forensics and
security, 8(12).
8. Zou, X., Dai, Y. S., & Bertino, E. (2008, April). A
practical and flexible key management
mechanism for trusted collaborative computing.
In INFOCOM 2008. The 27th Conference on
Computer Communications. IEEE (pp. 538-546).
IEEE.
9. Nabeel, M., Shang, N., & Bertino, E. (2013).
Privacy preserving policy-based content sharing
in public clouds. IEEE Transactions on
Knowledge and Data Engineering, 25(11), 2602-
2614.
10. Herranz, J., & Sáez, G. New identity-based ring
signature schemes. In ICICS (Vol. 4, pp. 27-39).

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