MUX induced Ring oscillators for encrypted Nano communication via Quantum Dot Cellular Automata

Abstract

In the present scenario of Nano communication technology, Quantum Cellular Automata (QCA) is a demanding Quantum concept to communicate information using quantum dots. This paper presents a novel QCA architecture employing majority gates in cross-coupled and cross-oriented structures in QCA designer platform. The selection of the structures in-turn depends on the minimum number of QCA cell usage. In the proposed methodology, an optimised Random Key Generator (RKG) has been constructed using QCA by employing a Linear Feedback Shift Register (LFSR) as a select input to the 2:1 MUX. The MUX generates a random key by selecting either Galois Ring Oscillators (GRO) or Fibonacci Ring Oscillators (FRO). Further, the proposed scheme reduces the Flip flop usage into EXOR gates and wire as compared to the conventional design. The clock circuitry used in the QCA platform would decide the initial seed to the FROs, GROs and the LFSR circuitry in QCA which makes the output Random Key Sequence truly unpredictable. The generated random numbers are used as a key to encode the pixels in the image which enhances the security. Further, the encoded image pixels are encrypted using Deoxyribo Nucleic Acid (DNA) encryption algorithm to render confusion, permutation and diffusion by adopting various rule sets. Image encryption metrics like correlation, entropy, Number of Pixel Change Rate (NPCR) and Unified Average Changing Intensity (UACI) were computed. Also, power and parameter analysis of the proposed QCA were estimated. From the computed metrics, it is proven that the proposed Nanostructure can be the potential aspirant for the future secured Nano communication.