DNA cryptography

What is DNA Cryptography?

DNA Cryptography is the branch of science that is used to encrypt and decrypt the data for hiding propose. It has a significant role in the field of the secure communication channel. The whole process of DNA cryptography was done by Leonard Max Adleman in the year of 1994. He said DNA cryptography is only possible by combining cryptology and modern biotechnology.

Why did we choose DNA cryptography?

1. DNA technology is one of the rapidly developing technologies in this world.
2. Mr. Adleman describes the process of solving complex problems very efficiently to the world. Hence DNA cryptography, like the NP-Complete problem and Hamilton path problem, helps the user to design more complex situations.
3. It gives new hope to the client that the more complex problem can be solved quickly. The reason is DNA cryptography provides the features of more speed, less storage and less power requirement. 
4. The memory allocation for DNA cryptography is about 1nm3/bit. But the regular storage for conventional is about 1012nm3/bit. 
5. In DNA cryptography, there is no need for power during the process of computation.
6. It will surprise us that one gram of DNA contains 1012 DNA which is equal to 108 TB of data. So we can store all the data that is available in the world in a few milligrams of DNA. 

DNA cryptography is also called hiding data in the sense of DNA sequence. DNA cryptography has a DNA algorithm same as RSA and DES algorithms. One of the primary functions of DNA cryptography is the public key system. 

In DNA, data encoding is possible only through the four nitrogenous bases. These bases are as follows:

1. Adenine (A)
2. Guanine (G)
3. Thymine (T)
4. Cytosine(C)

The simple method to represent these nitrogenous bases is as follows:

A(0) –00

T(1) –01

C(2)–10

G(3)–11 

There are 4!=24 methods available to encode this method. According to some principles, A combines with G, and T combines with C to make the pair. There are 24 methods available to pair, but pairing is possible in eight ways. The best encoding scheme is 0123/CTAG. 

So, after the conversion, our new sequence is A, T, G and C. Then, the implementation of these sequences is possible through the DNA synthesis technique. The method includes DNA synthesis Oligo Synthesis Platforms, and Chemical Oligonucleotide Synthesis. The Oligo Synthesis Platforms methods include Array-based Oligo Synthesis, column-based Oligo Synthesis, Complex Strand, Gene Synthesis, and Error Correction.  

For a better understanding, let's take an example of an XOR one-time pad and learn the implementation of DNA cryptography. 

Example

Let's take an example of the message and a key which are denoted as M and K, respectively. Then we have to find the cypher text by calculating M xor K = C. The user can decrypt the encrypted message by calculating C xor K = M xor K xor K= M. By doing this, we can able to return our old message. The implementation process of DNA cryptography takes place by following steps. These steps are as follows.

1. First, both the OTP keys and the message are converted to ASCII codes. 
2. In order to make the size of binary code even, we have to add zero padding to the message and the key. 
3. The KEY and the message are combined together by the XOR method. 
4. The output of XOR is displayed by the DNA format. This is the result of enciphered text.

Also, the decryption process of DNA cryptography takes place by following steps. These steps are as follows.

1. All the bases of DNA are converted to bits. 
2. Then we can retrieve the original text by XORed with the keys with bits.
3. The result is shown in binary code format, and then further, this binary code is converted to ASCII code. 

Similarly, users can implement other crypto algorithms like AES and DES. It stores data as a sequence of nitrogenous bases instead of storing data as a sequence of 0s and 1s. Storing information in the form of DNA enables us to store a lot of data in a small area.