الفهرس 
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Abstract
Day after day, scientists seek for developing more compact electronic chips and devices using in-hand technologies. Eventually, they will reach the end of current technology capabilities, colliding with the characteristics of physics. Therefore, scientists are searching for an alternative for silicon-based technologies to build feature computers. One promising consequence is biological computing, which has significantly promising capabilities over traditional electronic computers. On the other hand, the main backbone of any technology is its security, as the new data platform will require a new security approach. The pace of growth in information technology stimulates the information security field to rival to keep up at the same pace. Indeed, many approaches have been proposed to respond to this scarcity, and many other exertions have been spent. One promising consequence is DNA-based cryptography that emerged with the progress of the DNA computing field. from this perspective, the main idea behind this work is to bridge existing and promising technologies by accommodating existing encryption algorithms in order to be applicable on biological environment. Also, to create an encryption technique inspired by Deoxyribonucleic acid (DNA) characteristics. In this work, new enhanced methods will be proposed using properties of conventional cryptography with biological characteristics taken into consideration to produce DNA-based encryption techniques applicable to a biological environment. Also, we aim to produce more complex, robust, and less prone to attacks procedures. The presented work in this research can be summed up in four main aspects. First, a DNA-based advanced encryption standard (AES) technique has been proposed by adapting the classical AES technique to be applicable to implement in a biological environment (computer built from biological components) instead of silicon-based technologies. The proposed techniques accomplished by making its inputs (plaintext and key), internal procedures and accordingly its output to be DNA-based instead of binary data. The proposed approach is distinguished from what has been proposed previously by maintaining the same properties of the original algorithm to preserve the same security level. Second, an adaptable encryption technique was developed based on a sequence alignment reversing approach. The approach can be used as an extra layer of security to light weight encryption techniques and also to revive obsolete encryption technique. It can also be used as an additional security validation phase. Third, an encryption key transmission technique has been proposed in which the encryption key is inspired from DNA characteristics revealing a promising future of bio-inspired cryptographic techniques. Forth, using these three last-mentioned proposals to produce an enhanced version of the AES with an additional mode selection phase and modifying the ShiftRows function in the AES by the proposed reverse sequence alignment algorithm. The proposed AES with mode selection phase added an extra layer of security by making the internal steps depend on the key. The experimental analysis showed remarkable enhancement in testing the modified ShiftRows function detached, and the encryption strength added by the mode selection phase. Theoretically, the overall modified algorithm showed a significant advance over the classical AES in the resistance against linear cryptanalysis. The presented algorithms have been built on a DNA basis to demonstrate the capability of applying such a complex system to a promising biological environment, such as a molecular computer or biosensors. It must be clarified that the perception is not to negate or replace the mathematical and theoretical basis of the traditional cryptography, but to combine it with the sophisticated biological characteristics to produce a more powerful cryptographic technique, also to create a bridge between the existing and the new technologies. All the proposed techniques have been considered that they can be implemented either in biological or silicon environments. The experimental results showed that the DNA-based AES has identical properties to the classical AES. Also, the produced ciphertext has an equal value to the produced ciphertext from the classical AES, each in a different form. The results demonstrate the possibility of implementing the algorithm on a hybrid system (transmitting data from digital computer to computer composed of biological parts as biochip, DNA biosensor, and DNA digital coding storage, etc., or vice versa). The experimental results of the dynamic AES showed a great advance over the classical one added by the mode selection phase approach. The proposed reverse sequence alignment approach proved to enhance a lightweight encryption technique and outdated encryption techniques by adding an extra layer of security. Finally, the key generation approach has showed the possibility of generating encryption keys securely based on DNA characteristics.