Enhanced ID-Based Ring Signature by Validating Time Slots in Cloud Environment

 

Leeladhar A*, Prabadevi B

School of Information Technology and Engineering, VIT University, Vellore

 

ABSTRACT:

Sharing of Information has a number of problems, comprising integrity, information efficiency and safekeeping of data owner in cloud computing. Ring Signature methods are favorable choice to build an unidentified and authentic information sharing system. Ring have no managers, no setup systems, no denial systems, and no coordination: some person can pick any set of members that take account of himself, and sign message by making use of his secret key and the others' public keys, without getting their approval. By using Ring signatures we can leak top-secret information in an anonymous way. In the proposed Id-based ring signature the certificate validation process has been removed which is more cost effective. In this project we improved security in ring by implementing time slots i.e. if a super key of any user has lost then there is no need to change all the users’ keys including the lost key user. Security re-confirmation is avoided in ring Signature by using SHA Algorithm .We have also expanded the level of security in diminished time, easy and effective manner.

 

 

 

INTRODUCTION:

In distributed computing environment, there are a number of security problems concerns with cloud on the other hand these issues fall into two main categorizations: security issues challenged by cloud dealers and security issues faced by them. The objective goes both ways, in any case: the seller must conform that their framework is secure and their customer’s information and requests are secured while the client is in authority to strengthen their application also, make use of firm strong passwords and confirmation events. Distributed computing is the most widely adopted in the computing world because of its scalability and heterogeneous nature. It offers many significant points that could quickly benefit you and your business in any case, that important improvements go organized with regular difficulties.

 

On the fresh chance that you hold up a while, the association will undoubtedly grow all the more totally as issues are fixed. In addition, expenditure will go down as more people clasp the innovation, which is improbable news for any inexpensive minded specialist. “Internet is a metaphorical” over the place throughout the course of the world, the Internet is comparable to a cloud, sharing data by method for satellite systems. The data sharing in the cloud is very difficult especially when there are very large no of people who want to share as well as retrieve their own data. Confidentiality and security of the users also be compromised when there are very large no of people or participants in the cloud so we are proposing a theory in which the users can send their data anonymously [1] in the group i.e the user information is not known to anybody in the group but they can view the shared information in the cloud.

 

METHODOLOGY:

Information sharing is very difficult in public, private and hybrid cloud environment. The sharing of data or information is more difficult when it comes to large no of participants, security integrity and secrecy will be bottleneck. We are proposing id based ring signatures with time division technique. Here security is provided to the users in the way that if a security key of any user has lost there is no need to change the secrete key including that user. Mainly there are three problems in the existing system they are as follows.

 

Data Authenticity:

In the situation of Smart Grid, the statistic energy usage data would be misleading if it is forged by adversaries. one may encounter additional difficulties when other issues are taken into account, such as anonymity and efficiency.

 

Anonymity:

Energy usage data contains vast information of consumers, from which one can extract the number of persons in the home, the types of electric utilities used in a specific time period, etc. Thus, it is critical to protect the anonymity of consumers in such applications.

 

Efficiency:

The number of users in a data sharing system could be HUGE (imagine a smart grid with a country size), and a practical system must reduce the computation and communication cost as much as possible. Otherwise it would lead to a waste of energy.

 

Figure 1: Energy usage data center

 

ID-BASED SIGNATURES:

The identity ring based sign or mark based signature proposed  by  Rivert is successfully in sending the data anonymously but here the costly certificate validation or verification becomes bottleneck. The Keys can be used to generate signatures [2]. In the proposed system we are removing certificate validation process by taking the user public identity has a public key [3] here the public identity (email or unique phone no) is taken and the user who want to share the secret information will create the ring by adding all the members who the user want to share the secret information. The costly verification removes because if there are small group of members [4] we can validate the users and for example there is an organization if some employee want to share the secret information to the organization members then there will be a problem with verification process (suppose the organization has 2 members) here in this situation for every user we have to validate and therefore the validation cost increases. so we introduced id based ring signature that removes the validation process by simply taking user public identity has a public key. The private key generator then generates the keys for the user. The user can see the info from the ring if he is valid user.

 

An Exposure to Ring Signatures:

In the proposed enhanced id based ring signature by validating time slots the main profit is anonymity and security of the users here the package generates the secrete key for every user and the costly cortication validation and verification can be eliminated the generated sign is different for every user in the ring the id based ring is better explained by a real scenario which is not there in id-based ring signature [5,6]. It has following steps:

 

Step 1:

Suppose XYZ want to reveal some secret information then XYZ will create a ring by including all the public identities of the users or ring members.

 

Step 2:

XYZ uploads his personal shared data in the ring and make available for the ring members so that they can view the secret information.

 

Step 3:

By validating has a ring member one can see the secret information which is sent in the group. Here the private key generator generates the keys of users at every time limit. The process flow of the ring is continuous that is if the users in the ring are not using the ring slowly the time expires for the users at a particular time the ring users expired i.e. the ring is no longer available. The user after login with their credentials user has to give the electronic usage and generate signatures the following diagram depicts the ring signatures and the electronic usage in the ring.

 

Figure 2: Users in ID-based ring signature

 

Proposed System:

In this enhanced id based ring signature the time slot techniques is proven to be efficient and can use in real world applications in a cost effective manner. The time chart for each ring can be shown in the graph. If the users are not using the ring the time slowly decreases once the time comes to zero the graph is not shown in the graph table, because when t= 0  the ring expires and it is deleted from the graph table. Here the time is continuous that is if the ring users are using the ring then the time will increase to provide better security. The main achievements of the project is security and

1) Removal of verification validation process of ring users

2) The size of the secret key is just one integer in the ring environment.

3) If the secret key has lost the key updating is also very easy we don’t require any pairing at any stage. While uploading the user data the security is maintained

 

2.3 Pseudo Code for Data Upload in Cloud

BEGIN

Step –1 Read file

Step –2 Cloud server checks for duplication

Step –3 Sends duplication response whether the file already exists or not

Step – 4 If the file does not exist

           4.1 Display “file does not exist”

Step – 5 Then it uploads the file

Step – 6 If the file already exist

6.1 Display “file already exist”

END

 

RING SIGNATURE:

The ring signature or mark signature was introduced by Rivert mark, was proposed in the year 1984.The main aim of ring signature is to send the message or information anonymously in the group. Here the user who wants to share secret information or message has to initiate a ring. The user will add all the members to the ring by taking their public identity. The user generate signatures and upload the date to cloud all the members who are there in the ring can view the information and they don’t know who send or share this information thus anonymity is maintained in sharing the information the below diagram depicts the ring structure.

 

Figure.3 Ring signature schema

 

ENCRYPTION TO GENERATE SIGNS:

A family of two similar hash functions, with different block sizes, known as SHA-256 and SHA-512. They differ in the word size; SHA-256 uses 32-bit words where SHA-512 uses 64-bit words. There are also truncated versions of each standard, known as SHA-224, SHA-384, SHA-512/224 and SHA-512/256. These were also designed by the NSA.

 

Step 1: Append Padding Bits…. Message is “padded” with a 1 and as many 0’s as necessary to bring the message length    to 64 bits fewer than an even multiple of 512.

Step 2: Append Length....64 bits are appended to the end of the padded message. These bits hold the binary format of 64 bits indicating the length of the original message.

Step 3: Prepare Processing Functions

Step 5: Initialize Buffers

Step 6: Processing Message in 512-bit blocks (L blocks in total message)

 

Figure 4 System Process Flow

SYSTEM PROCESS FLOW:

The user uploads the data into the cloud. At that particular time signature is generated and the ring members can view the message that is there in the cloud but no one knows who send the message.

 

Key Disclosure in Distribution system:

The key disclosure is a big problem in the cloud environment [9]. Several mechanisms for securing the key is available in the literature [7,8,10,11]. If the user lost the key, the other users who are there in the group or ring should change the secret key. If the secret key of any user has lost then the intruder can generate the signature using that key and see the information which is shared in the group.in this project we are introducing time slot technique which provides security to the ring users that is if the ring user lost or compromised with the secret key all the users or customers need not change the key including that user. Here we are generating signatures at every particular time if the user lost the key at a time t= 1 then we have to change the key generation at that particular time slot this method is effective and can be used in many applications

 

Figure 5: Time division in ring based environment Time chart for Various Rings

 

The below fig depicts various time charts for various ring groups

 

Figure 6 Time chart for various ring signatures

SYSTEM SETUP:

Algorithm:

Step1: Keygen (sk, k).Keygen is mainly used for generating the secret key to encrypt  documents and indexes.

Step2: Index (Dc, sk) ->In By using the above generated secret key we can create Encrypted Index. In mean time the clustering process will also start.

Step3: Encr (Dc, k) ->Here SHA encryption algorithm will used for encrypting the documented collection for achieving higher security.

Step4: User (v, sk) -> User data which is encrypted with the help of secret key and user input keywords.

Step5: Decr (E, k) ->F.The final Encrypted files are finally decrypted by key generated in the initial step.

To enhance the Security, A (1, n) ID-Base Ring Signature (IDRS) scheme is a tuple of probabilistic polynomial- time (PPT) algorithms is used.

 

Fig 7: Generating signatures for users

 

The data will also available for certain time slot. The signature are created for different timeslots if at a particular time slots the secrete key of one user is lost the there is no need to change all the consumers details.

 

Figure 8 Time slots for rings

 

Try to test the information after a month for a existing user then we can see that the user is expired because the time charts are expired and Current customer is incapable to view the information as the time is expired.

 

Figure 9 Expiration of the ring

 

CONCLUSION:

Ring Signature methods are favorable choice to build an unidentified and authentic information sharing system. Ring have no managers, no setup systems, no denial systems, and no coordination. Time division schema provides better and efficient security to the users in the ring. This scheme provides unconditional anonymity and is proven secure in experimental analysis. Our scheme is very efficient and does not require any pairing operations. The size of user secret key is just one integer. We believe our scheme will be very useful in many other practical applications, especially to those require user privacy and authentication, such as ad-hoc network, e-commerce activities and smart grid.

 

REFERENCES:

1.       Xinyi Huang, Joseph K. Liu+ Cost-Effective Authentic and Anonymous Data Sharing with Forward Security,2015.

2.       M. Abe, M. Ohkubo, and K. Suzuki. 1-out-of-n Signatures from a Variety of Keys. In ASIACRYPT 2002, volume 2501 of Lecture Notes in Computer Science, pages 415–432. Springer, 2014.

3.       R. Anderson. Two remarks on public-key cryptology. Manuscript, Sep. 2000. Relevant material presented by the author in an invited lecture at the Fourth ACM Conference on Computer and Communications Security, 2012.

4.       G. Ateniese, J. Camenisch, M. Joye, and G. Tsudik. A Practical and Provably Secure Coalition-Resistant Group Signature Scheme. In CRYPTO 2000, volume 1880 of Lecture Notes in Computer Science, pages 255–270. Springer, 2010.

5.       M. H. Au, J. K. Liu, T. H. Yuen, and D. S. Wong. Id-based ring signature scheme secure in the standard model. In IWSEC, volume 4266 of Lecture Notes in Computer Science, pages 1–16. Springer, 2006.

6.       A. K. Awasthi and S. Lal. Id-based ring signature and proxy ring signature schemes from bilinear pairings. CoRR, abs/cs/0504097,2005.

7.       M. Bellare, D. Micciancio, and B. Warinschi. Foundations of group signatures: formal definitions, simplified requirements and a construction based on general assumptions. In Eurocrypt’03, volume 2656 of Lecture Notes in Computer Science. Springer, 2003.

8.       M. Bellare and S. Miner. A forward-secure digital signature scheme. In Crypto’99, volume 1666 of Lecture Notes in Computer Science, pages 431–448. Springer-Verlag,1999.

9.       J.-M. Bohli, N. Gruschka, M. Jensen, L. L. Iacono, and N. Marnau. Security and privacy-enhancing multicloud architectures. IEEE Trans. Dependable Sec. Comput., 10(4):212–224, 2013.

10.     A. Boldyreva. Efficient Threshold Signature, Multi signature and Blind Signature Schemes Based on the Gap Diffie-Hellman Group Signature Scheme. In PKC’03, volume 567 of Lecture Notes in Computer Science, pages 31–46. Springer, 2003.

11.     D. Boneh, X. Boyen, and H. Shacham. Short Group Signatures. In Csrypto 2004, volume 3152 of Lecture Notes in Computer Science, pages 41–55. Springer, 2004.

 

 

 

Received on 07.09.2016          Modified on 10.10.2016

Accepted on 20.11.2016        © RJPT All right reserved