Biblio

This paper proposes a double-layer message security scheme that is implemented in two stages. First, the secret data is encrypted using the AES algorithm with a 256-bit key. Second, least significant bit (LSB) embedding is carried out, by hiding the secret message into an image of an information matrix. A number of performance evaluation metrics are discussed and computed for the proposed scheme. The obtained results are compared to other schemes in literature and show the superiority of the proposed scheme.

The start-up value of an SRAM cell is unique, random, and unclonable as it is determined by the inherent process mismatch between transistors. These properties make SRAM an attractive circuit for generating encryption keys. The primary challenge for SRAM based key generation, however, is the poor stability when the circuit is subject to random noise, temperature and voltage changes, and device aging. Temporal majority voting (TMV) and bit masking were used in previous works to identify and store the location of unstable or marginally stable SRAM cells. However, TMV requires a long test time and significant hardware resources. In addition, the number of repetitive power-ups required to find the most stable cells is prohibitively high. To overcome the shortcomings of TMV, we propose a novel data remanence based technique to detect SRAM cells with the highest stability for reliable key generation. This approach requires only two remanence tests: writing `1' (or `0') to the entire array and momentarily shutting down the power until a few cells flip. We exploit the fact that the cells that are easily flipped are the most robust cells when written with the opposite data. The proposed method is more effective in finding the most stable cells in a large SRAM array than a TMV scheme with 1,000 power-up tests. Experimental studies show that the 256-bit key generated from a 512 kbit SRAM using the proposed data remanence method is 100% stable under different temperatures, power ramp up times, and device aging.

Digital signatures now become a crucial requirement in communication and digital messaging. Digital messaging is information that is very vulnerable to be manipulated by irresponsible people. Digital signatures seek to maintain the two security aspects that cryptography aims, such as integrity and non-repudiation. This research aims to applied MAC address with AES-128 and SHA-2 256 bit for digital signature. The use of MAC address in AES-128 could improve the security of the digital signature because of its uniqueness in every computer which could randomize the traditional processes of AES. SHA-2 256-bit will provides real unique randomized strings with reasonable speed. As result the proposed digital signature able to implement and work perfectly in many platforms.