DNA-Based Information Encryptiong Algorithm

Based on Computational science and molecular biology, DNA computing is a fast developing interdisciplinary area. As the DNA molecule has massive storage density and highly capacity of parallel calculation, DNA computing is a big challenge to the traditional cryptography which is based on the computational security. On the basis of the highly development of DNA computing, the DNA cryptography is emerged and become a frontier in international cryptography research.At recently, DNA computing’s applications in cryptography, mainly contain these parts: First, one code from a codebook which is based on a mass storage density of the DNA molecules is used to encrypt in one time; Second, according to DNA molecules’highly capacity of parallel calculation, codes can be cracked; Third, Based on the biological complexity of DNA computing, data can be hidden. This paper mainly involves the second part—according to DNA molecules’highly capacity of parallel calculation, codes can be cracked.In this paper, the background of DNA cryptography and the biological knowledge which is related to DNA computing is introduced firstly, and at the same time, the principles of DNA computing and the current models of DNA computing is overviewed. On this basis, we design a decoding method of the SMS4cryptography system which is based on DNA.At first, the algorithms of SMS4cryptography system are analyzed. Then, the decoding method of SMS4cryptography system is introduced, which is included the following steps: first step, sticker model of DNA computing is used to encode the key space of SMS4cryptography system in the lth to256th places of DAN strand; Second step, plaintext in the129th to256th place of each DNA strand is generated; Third step, the cipher text is gained from the encrypting with every key in the key space and the plaintext, which are produced in the encoding process of different keys and the same plaintext; At last, depended on128times separation operation, the encrypted key is generated.The last step, the result is emulated by C++programming language to mainly verify the feasibility of DNA computing.