Novel true random bit generation and its audio encryption application with Lorenz chaotic circuit-based entropy source

Abstract

This paper introduces a methodology for generating secure cryptographic key bits from analog values obtained from the Lorenz chaotic circuit. The analog values are transferred from the chaotic circuit to the computer via an Analog Discovery-2 device and then post-processed by using a fixed-point number representation format and Von-Neumann corrector for the sampled values on the MATLAB program. By employing this method, the analog values are digitized and randomized as the main idea is to obtain secure and efficient statistically random bits. Furthermore, the generated random bits are utilized for secure audio encryption by demonstrating a practical application of the proposed methodology. In addition to the classical randomness test criteria, NIST 800.22 statistical test suite, the throughput bit stream is also subjected to Chi-square and FIPS 140-1 tests to further evaluate its effectiveness. The results of these comprehensive tests confirm the successful performance of the proposed system in generating statistically random bits and its secure audio encryption system. The utilization of the Lorenz chaotic circuit as an entropy source in generating true random bits for secure audio transmission applications showcases the potential of the proposed system.

Keywords

• Audio Encryption
• Chaos
• Post-processor
• Random Number Generator
• Statistical Tests

Lorenz kaotik devre tabanlı entropi kaynağı ile özgün gerçek rasgele sayı üretimi ve ses şifreleme uygulaması

Öz

Bu makale, Lorenz kaotik devresinden elde edilen analog değerlerle güvenli kriptografik anahtar bitleri üretme yöntemini tanıtmaktadır. Analog değerler, kaotik devreden Analog Discovery-2 cihazı aracılığıyla bilgisayara aktarılır ve ardından MATLAB programında örnekleme değerleri için sabit noktalı sayı formatı ve Von-Neumann düzeltici kullanılarak işlenir. Bu yöntemi kullanarak, ana fikir güvenli ve verimli istatistiksel olarak rasgele bitler elde etmektir, bu nedenle analog değerler sayısallaştırılır ve rasgele hale getirilir. Ayrıca, önerilen yöntemin pratik bir uygulamasını göstererek üretilen rasgele bitler güvenli ses şifreleme için kullanılmaktadır. Klasik rasgelelik test kriteri olan NIST 800.22 istatistiksel test paketine ek olarak, üretilen bit dizisi ayrıca Chi-square ve FIPS 140-1 testlerine tabi tutularak etkinliği daha fazla değerlendirilmektedir. Bu kapsamlı testlerin sonuçları, önerilen sistemin istatistiksel olarak rasgele bitler üretme ve güvenli ses şifreleme sisteminde başarılı bir performans sergilediğini doğrulamaktadır. Lorenz kaotik devresinin bir rasgelelik kaynağı olarak kullanılması, önerilen sistemin potansiyelini göstermektedir.

Anahtar Kelimeler

• Ses Şifreleme
• Kaos
• Son-işlemci
• Rasgele Sayı Üreteci
• İstatistiksel Testler

Kaynakça

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