Multi-Level Cryptography and Steganography Frameworks for Secure Wireless Communication Systems: A Comprehensive Review

Abstract

The rapid expansion of wireless communication technologies, including the Internet of Things (IoT), cloud computing, and emerging 5G/6G networks, has intensified the demand for security frameworks capable of simultaneously protecting data confidentiality and concealing the existence of sensitive information. This review provides an in-depth and balanced overview of the latest developments in cryptography and steganography for secure wireless communication systems. The existing cryptographic methods can be divided into symmetric, asymmetric, chaotic, lightweight and post-quantum cryptographic methods, while modern steganographic approaches are classified into spatial-domain, transform-domain, adaptive, and deep learning-based methods. The review further compares representative hybrid cryptography--steganography frameworks in terms of security level, computational complexity, embedding capacity, imperceptibility, processing latency, and resistance to cryptanalysis and steganalysis. According to the critical analysis, the use of combinations of lattice-based post-quantum cryptography, chaotic encryption, and hash-guided or intelligent steganographic embedding can offer complementary protection, but their application in practice is limited by the computational resources required and by the lack of sufficient testing in real-world scenarios. Finally, the review identifies key research gaps and outlines future research directions involving artificial intelligence, lightweight security architectures, post-quantum cryptography, and intelligent information hiding for next-generation wireless communication systems.