Design and Implementation of Chao-Cryptic Architecture on FPGA for Secure Audio Communication

The emerging growth in communication arena firmly demands a secure channel and needless to mention that security and privacy of the user are the top priorities in audio communication. To transmit audio signals safely, cryptography is being adopted widely. Chaos-based cryptography is one of the effective strategies that attract researchers to develop more techniques. Characteristics of chaotic systems such as ergodicity and stochasticity are the main motivators for using them in encryption schemes. This work presents an field programmable gate array (FPGA) governed chaotic audio encryption scheme based on Lorenz attractor. This scheme of encryption undergoes two consecutive steps of operations, namely confusion by linear feedback shift register (LFSR) and diffusion through the random numbers generated in X, Y, and Z planes of the chaotic attractor. A study has also been carried out to analyze the best diffusion from the obtained results. Evaluation of the proposed scheme includes entropy, correlation, histogram, PSNR, and MSE. Further, NIST SP 800-22 batteries of test have been performed to ensure that the encrypted audio data possesses more randomness. Moreover, this work consumed 15,422 logic elements and 14.22 mW of dynamic power to accomplish the design. Noticeably, the proposed work has achieved 10.346 Mbps as a throughput to encrypt 216 × 16 bit samples of audio data.