1 Designing a New Efficient Hybrid DNA Cryptographic System

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Designing a New Efficient Hybrid DNA Cryptographic System: A Comparative Analysis Vikasbhai Pawar1, Ninad Sawant2, Viraj Malekar3, Prof. A.M.Hingmire4
1 B.E. Computer Engineering student, Vidyvardhini’s College Engineering Mumbai, Maharashtra, India, [email protected] 2B.E. Computer Engineering student, Vidyvardhini’s College Engineering Mumbai, Maharashtra, India, [email protected] 3B.E. Computer Engineering student, Vidyvardhini’s College Engineering Mumbai, Maharashtra, India, [email protected] 4Professor, Vidyavardhini’s College Engineering Mumbai, Maharashtra, India, [email protected]
Abstract In today’s modern world of technological advancement modifications to the system are made according to the user choice. This may lead to much security loopholes which are easily recognizable by the attackers. DNA Cryptography is the latest and new technique which is based on the Helical structure of DNA molecule. ssDNA is preferred for DNA cryptography which has four nucleotide bonds complementary to each other. The main objective of this project is to design a system that is reliable, efficient, and robust for secure message transmission. A group of words are arranged in the random sequence of four DNA bases that makes up the human DNA (Deoxyribonucleic Acid).The algorithm introduced in this paper is compared to the existing algorithms against various parameters and according to the results a suitable algorithm is suggested.
KeyWords: Encryption, Decryption, Single Stranded DNA, Hybrid DNA technique …etc
I. INTRODUCTION
With growing speed of internet and network advancement the security threats are increasing tremendously. 50% growth in cybercrime is observed in past few decades which involve trespassing the Security barriers, hacking various social accounts, Stealing confidential information. There are various adversaries who always try to break into system in to steal crucial information in order to damage the integrity of data and to use it for blackmailing or to destroy the redeemed organization. This is why it is very important to prevent the modern security systems from these threats and attacks. From the past few decades many security mechanisms are proposed and Cryptography and Steganography are most commonly used techniques. Cryptography is a technique where a set of alphabets or sequences is encrypted in a special format which can be only decrypted by the intended person. DES, AES are some cryptographic algorithms which are used for long lime. In cryptography the encryption/decryption of data/plaintext is done with the help of key. The latest reliable, secure and fast technique for securing data using the biological structure of DNA was introduced which is called DNA Computing (A.K.A molecular computing or biological computing). 1It was originated and proposed by Leonard Max Adleman in year 1994 for suggesting and proposing a solution for complexed and difficult problems such as the directed Hamilton path direction problem and NP-complete path tracing problem
similar to The Traveling Salesman problem. He is considered as one of the member of RSA algorithm – an algorithm that is used to define and improve the industrial standards of cryptography which is used to send data over web. This approach of cryptography was taken into consideration by many researchers and scientist for reducing the storage size of data that made the data transfer faster and secure. DNA can be used to store and transmit data. 2 The recent technology based on DNA cryptography was One-Time-Pad(OTP). It uses the concept of complementary DNA strand and generates a random sequence along with a shared private key is sent to the receiver. 3There is also a method called as index based symmetric DNA encryption algorithm which uses a symmetric key. This new concept of using DNA computing in the fields of cryptography and steganography has been recognized as a possible technology that may bring forward a new hope for unbreakable algorithms. Strands of DNA are long polymers of millions of linked nucleotides. These nucleotides consist of one of four nitrogen bases, a five carbon sugar and a phosphate group. The nucleotides bases that forms these polymers are named after the nitrogen base that it consists of: Adenine (A), Cytosine (C), Guanine (G) and Thymine (T). Structurally this means we can utilize this 4 letter alphabet ? = {A, G, C, and T} to encode information, which is more than enough considering that an electronic computer needs only two digits, 1 and 0, for the same purpose. The inspiration behind the using human DNA structure for cryptography is because of its space compatibility. The main objective of DNA cryptography is based on encryption of

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message in DNA digital form and the decrypting it on receiver’s side. DNA cryptography ensures the Confidentiality, Integrity and Availability of data which is the basic requirement of security. Encrypting the data/plaintext using Transposition, Folding and ssDNA complementary operations is the basic approach of algorithm. Researchers and scientist are continuously searching for an adaptive technology for improving encryption methods. After failure of many cryptographic algorithms in latest network attacks it is imminent for a reliable system and algorithm mentioned in the paper is a good replacement.
Real World problems with existing algorithms based on DNA cryptography 1. More space required to store message 2. Compatibility on all the systems 3. Time required is more for processing 4. Precise result is not obtained 5. Security loopholes can be formed
II. BIOLOGICAL BACKGROUND
DNA(Deoxyribonucleic acid) is one of the major components in human body which stores all the genetic data of an individual. It is a thread like structure which has the information about development, growth, reproduction of the individual. DNA is very compact structure which can able to store tremendous amount of data in a single molecule. DNA is a long polymer of deoxyribonucleotides. Chemically, DNA is compared to three components of a pentose sugar, phosphoric acid and four types of nitrogenous bases. Pentose sugar in DNA is deoxyribose sugar. The four nitrogenous bases belongs to two sequence groups purines which are two-ringed nitrogen compound and includes adenine(A) and guaninie(G) and pyrimidines which are formed of one ring only and include Thymine(T) and Cytosin(C). James Watson and Francis Creek proposed DNA consist of two strands, which are helically coiled. The two strands are said to be complementary. The strands are said to be AntiParallel i.e one in5′?3′ direction and the other in 3′?5′ direction. There are two hydrogen bonds between A and T and three between G and C. The stacking of bases creates two types of grooves called major and minor grooves. Each turn accommodate 10 bases. The pitch of the helix is 3.4 nm. The DNA model, irrespective of its source, always has the A—T base pairs equal in number to the G—C base purines. The purines and pyrimidines are always in equal proportion ,i.e A+T=G+C. The amount of adenine is always equal to that of thymine and the amount of guanine is always equal to that of cytosine i.e A=T and G=C . However, the amount is not necessarily equal to G+C.
Fig 1: Architecture Of DNA Strand
III. PROPOSED METHODOLOHY
The proposed methodology is a combination of various operations which involves transposition, shifting, and single stranded complementary approach. Transposition approach is performed to change the location of data matrix element. Folding operation shuffles one of the element with another like a paper fold. A. Encryption
Encryption process converts ASCII values into binary into 8- bit binary format and them substitute the values for a combination of various binary bits. Now transposition matrix is performed in an irregular fashion like an s curve and we obtain cipher text in 16- bit format. Folding operation is performed on the transposed matrix in three ways – row folding, column folding and diagonal folding. Now Algorithm
1) Convert the Plain Text into it’s respective ASCII value and then into 8 bit binary format. 2) Substituting binary value into ATGC format. a) 00-A b) 01-T c) 10-G d) 11-C 3) Now perform the Transposition operation in Zig-Zag manner on obtained cipher text in 16 bit, 4×4 format.

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4) After the Transposition operation perform the folding operations on row, column and diagonally. 5) Now compliment the obtained cipher text by its corresponding DNA compliment.
a) A-T b) G-C
Fig 2: Flow Chart for Encryption
B. Decryption Decryption process is reverse of encryption process which follows the entire procedure in the reverse order.
Algorithm
1) Perform the DNA compliment operation on the obtained string. a) A-T b) G-C 2) Now perform 16 bit, 4×4 tabular reverse Folding operation 3) After that perform the Reverse Transposition operation on obtained table 4) Re-substitute the value of DNA stands A,T,G,C as (A=00,T=01,G=10, C=11) 5) Convert 8 bit format into ASCII and recover the Plaintext
Fig 3: Flow Chart for Decryption

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IV. EXAMPLE AND ILLUSTRATION
Step 1- For example if user enter the text
Step 2- Their respective ASCII value.

Step 3- Their binary value

Step 4- After substitution
Step 5- Form 16 bit table

Step 6-Perform Transposition

Step 7- Perform folding

Step 8- Perform DNA Compliment
Step 9- Obtained Encrypted string is

Step 10- Decryption process convert the string into 16 bit format (4×4 table).

Step 11- Reverse DNA compliment

Step 12- Reverse Folding operation

Step 13- Reverse transpose matrix

Step 14- Convert it into binary format
Step 15- Recovered string is

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V. RESULTS
After going through various test methods and trying the algorithm for various scenarios we have created a table of comparative study based on the amount of messages that it takes as input to send to the receiver. The storage requirement is menioned in the table with the help of varying message size. This give analysis of a bestter suggestion for algorithms incuding the hybrid DNA algorithm.
Length Of Encrypted String
TFS DNA Encryption Algorithm
Feistel DNA Encryption algorithm 1 16 bytes 20 bytes 2 16 bytes 25 bytes 4 16 bytes 50 bytes 8 32 bytes 105 bytes 16 64 bytes 252 bytes

VI. CONCLUSION
In this paper we have suggested DNA cryptography various methods and also discussed about the comparison factors between the latest and the proposed methodology. The methodology proposes a strong approach for encrypting and decrypting of messages which is strong against brute force attacks. The concept of transposition and shifting with complementary DNA strands make it more resistant against cyber attacks. search for a new approach to the existing module which fascinates them about various concepts and this can be new technique.
The algorithm can also be integrated with the DNA nano chips that were invented in recent time. Researchers are always in Advantages- 1. Secure, Reliable and Robust system with minimal errors 2. Fast and time efficient in very aspects
Disadvantages-Too many messages can cause increase in time for receiver to obtain the message
Future Scope
The DNA cryptography can be used as in the recent systems such as following 1. Can be used for website transmission of data 2. Can be used for handling very secure data 3. Can be used to secure mobile systems

VII. REFRENCES
1 “Molecular computation of solution to combinatorial problems Science”, by L. M. Ad leman, in (1994) 11, (266): 1021-1024.
2 “Feistel Inspired structure for DNA cryptography” by Ashish kumar kaundal, in June (2014).
3 “DNA cryptography based on DNA Fragment assembly,” by Yunpeng Zhang, Bochen Fu, and Xianwei Zhang, , At Information Science and Digital Content Technology (ICIDT), IEEE International Conference on, vol. 1, pp. 179-182, (2012)..
4″Lightweight Symmetric Encryption Algorithm for Secure Database” by Hanan A. Al-Souly, Abeer S. Al-Sheddi, Heba A. Kurdi Computer Science Department, Computer and Information Sciences College Imam Muhammad Ibn Saud Islamic University Riyadh, Saudi Arabia.