Data Security by Hide and Retrieval Method Using Rotation Cipher

Satish Garg¹, Priyanka Vaishist¹, S. P. Gupta²

¹Govt. P G College Ambala Cantt. - 133001

²University College Kurukshetra-136118

*Corresponding Author Email: sat.phy@gmail.com, priyanka.18@gmail.com, spgupta@kuk.ac.in

ABSTRACT:

In the present work the authors have suggested a new symmetric key cryptographic method where rotation cipher is applied on digitized form of plain text. In this method the sender first converts the plain text into digital form by using 8 bit ASCII Code and then apply rotation cipher on this digitized plain text, thus hiding the original text. This digital message is sent to the receiver who can decrypt.

KEYWORDS: Encryption, Decryption, Rotation Cipher.

I. INTRODUCTION :

The internet technology is being used almost in every field and is developing at very fast speed [1-2]. The security and originality of data has now become very challenging because there is always a possibility that anyone may intercept our data. So it is not safe to send confidential data from one computer to another computer. The confidential data may be bank statements, bank transaction, military information, confidential data of companies etc. Hence the data should be protected from any unwanted intruder otherwise any massive disaster may happen all on a sudden. In order to make secure the system one should consider the security primary attributes such as confidentiality, integrity and availability, and secondary attributes such as authenticity, non-repudiation and accountability etc. There are a large number of methods and techniques to achieve security goals, one of these is Cryptography. Cryptography is a method of converting meaningful message into a form which seems to meaningless to any hacker and the hacker may not be able to recover the original message [3-4]. The cryptographic algorithm can be classified into two categories: (i) Symmetric Key Cryptography where one key is used for both encryption and decryption purpose. (ii) Public Key Cryptography where two different keys are used one for encryption and the other for decryption purpose. In the present work the authors have introduced a new symmetric key cryptographic method using rotation cipher. In the proposed algorithm, following steps are involved :

(i)	Firstly all the characters are converted in binary form using 8 bit ASCII Code
(ii)	Then Rotation Cipher is used on the resultant binary string, whereby position of the bits are displaced towards Left/Right or vice versa in a circular queue and
(iii)	Finally, 8 bit ASCII Code is used to convert the bits obtained at step (ii) into corresponding characters and thus encrypted output is obtained.

II. THEORY :

This algorithm is based on the concept that each character is represented by a unique 8-bit code in ASCII Code system and if one or more bits are changed in a 8-bit code[6], then corresponding character is entirely changed. When any text of 10 characters is converted into binary form we get 80 bits which contains about 50% of 0’s and 1’s each. Therefore, total number of possible combinations is about 80!/(40!)²= 1075×10²⁰. The Super Computer available is Teraflop which is capable of doing 10¹² floating point calculations per second, so a teraflop super computer shall take about 3409 Years to find all possible combinations. This time is sufficiently large for any message to reside on any network [5].

III. PROPOSED ENCRYPTION ALGORITHM:

1. Read the input string of characters and Check the number of characters, N

2. If N<10, then write PROGRAM IS NOT APPLICABLE

3. Convert characters into Binary Form using ASCII (8 bit) Code, we get

8N Bits

4. Rotate the bits in circular queue towards Left/Right by N1 places

5. Convert Binary string obtained at Step 4 into characters using ASCII

(8 bit) Code, we get N Characters

6. Output is Encrypted String

VIII. RESULTS AND DISCUSSION:

We have implemented the proposed algorithm on Java platform for different values of N1 = 1 to (8N-1). From the Table 2, it is clear that if we change the value and or direction of rotation of the key N1, then the cipher text is entirely different for the same plain text. Further, the proposed algorithm is successful for encryption of any plain text consisting of 10 or more characters and minimum time required to crack such code using a teraflop super computer may be about 3000 Years which is sufficiently large.

IX. REFERENCES:

1. S. K. Garg, Review of Secured Routing for Wireless Ad hoc Network, International Journal of Computing and Business Research, Vol. 2 (1), 2011.

2. S. K. Garg, Wireless Network Security Threats, International Journal of Information Dissemination and Technology, Vol. 1 (1), 2011.

3. T. Karygiannis and L. Owens, Wireless Network Security, NIST Special Publication, 2002

4. William Stallings, Cryptography and Network Security: Principles and Practice, Prentice Hall, 5^th Edition, 2011.

5. R. H. Karpinski, Reply to Hoffman and Shaw, Datamation, Vol. 16(10) p. 11 (Oct. 1970)

6. S. K. Garg, Data Security By Shifting Bits: Algorithm SKG 2.1, International Journal of Computer Science and Communication, Vol. 5(1), 80-81, 2014.

Received on 27.08.2016 Accepted on 12.09.2016

Int. J. Tech. 2016; 6(2): 59-62.

DOI: 10.5958/2231-3915.2016.00009.2