An enhanced DNA sequence table for improved security and reduced computational complexity of DNA cryptography

Abstract

Recently, DNA cryptography rejuvenates the art of secret writing by combining biological information and cryptography. DNA’s double-helical structure serves as a template for encoding decoding information, vast storage and randomness. The structure includes DNA encryption that uses a DNA sequence table to substitute plaintext into the DNA sequence. However, this encoding table can result in leakage of information about the plaintext, character frequency, and key, by carefully examining the ciphertext through frequency analysis attack. Therefore, this paper proposes an enhanced DNA table for all 96 printable ASCII characters which are created to improve the entropy so that the probability of each encoding base (A, T, C, G) is equally likely and to reduce the computational complexity of DNA cryptography. An algorithm has been selected to implement both tables for performance measurement. The results show that encoding and encryption time is reduced, high entropy ciphertext, better frequency distribution ciphertext is obtained. Information leakage in terms of conditional entropy is also reduced by the proposed table. In conclusion, the proposed table can be used as a DNA sequence table in DNA cryptography to improve overall system security.