Quantum computing threatens classical cryptography and the convergence of quantum key distribution (QKD), and steganography offers an unconditionally secure hybrid approach for postquantum communication. QKD ensures provable secrecy via quantum mechanics, while steganography conceals the existence of communication providing stealth and plausible deniability. This systematic review explores integrated frameworks that combine QKD with classical and quantum steganographic techniques to enhance confidentiality, integrity, and undetectability. The study categorizes existing hybrid models and evaluates their performance using metrics such as quantum bit error rate (QBER), entropy, and imperceptibility. It examines quantum steganographic protocols including quantum LSB, entangled‐state hiding, and covert key transmission, analyzing their resilience against quantum noise and steganalysis. Despite promising simulation tools and real‐time QKD implementations, challenges remain in scalability, interoperability, and formal security guarantees. This review identifies key limitations in current systems and highlights future directions for developing robust, scalable, and stealth‐aware quantum–classical security frameworks. To the best of current knowledge, this is the first systematic synthesis of hybrid QKD–steganography frameworks offering a novel taxonomy and critical analysis to advance secure communication infrastructures in the postquantum era.
Quantum computing threatens classical cryptography and the convergence of quantum key distribution (QKD), and steganography offers an unconditionally secure hybrid approach for postquantum communication. QKD ensures provable secrecy via quantum mechanics, while steganography conceals the existence of communication providing stealth and plausible deniability. This systematic review explores integrated frameworks that combine QKD with classical and quantum steganographic techniques to enhance confidentiality, integrity, and undetectability. The study categorizes existing hybrid models and evaluates their performance using metrics such as quantum bit error rate (QBER), entropy, and imperceptibility. It examines quantum steganographic protocols including quantum LSB, entangled‐state hiding, and covert key transmission, analyzing their resilience against quantum noise and steganalysis. Despite promising simulation tools and real‐time QKD implementations, challenges remain in scalability, interoperability, and formal security guarantees. This review identifies key limitations in current systems and highlights future directions for developing robust, scalable, and stealth‐aware quantum–classical security frameworks. To the best of current knowledge, this is the first systematic synthesis of hybrid QKD–steganography frameworks offering a novel taxonomy and critical analysis to advance secure communication infrastructures in the postquantum era.
In response to rising cyber threats and the limitations of traditional security, this project proposes a hybrid framework combining quantum cryptography and text-based steganography for secure and concealed communication. Using the BB84 Quantum Key Distribution (QKD) protocol, a secure quantum key is established and extended with SHA-256 to encrypt a secret message via XOR operations. The encrypted data is embedded into a cover text using three steganographic techniques: case-based, zero-width, and color-based methods, the latter including double-color and double-color overlay variants. The techniques are evaluated on embedding efficiency, payload capacity, entropy, and deviation percentage. Among them, double-layer color-based steganography demonstrates superior performance, achieving up to 6 bits/symbol and 95% efficiency, with minimal error and high integrity. The system is implemented using Qiskit and HTML rendering, validating its practical feasibility. This dual-layer security model ensures confidentiality and invisibility, offering a robust, quantum-enhanced approach to secure communication in sensitive applications.
In recent times, secure data transmission become crucial requirement because of increasing growth of threats and emergence of quantum computing technologies. However, existing Quantum Key Distribution-Advanced Encryption Standard-Least Significant Bit (QKD-AES-LSB) struggled with two main limitations such as restricted resistance to future quantum attacks because of dependence on classical encryption and vulnerability of static LSB steganography for improved Machine Learning (ML) approaches. To address these challenges, Quantum Key Distribution-Post-Quantum Cryptography-Adaptive Steganographic Encryption framework (QKD-PQC-ASE) is proposed. Primarily, secret data and cover images are gathered then quantum key is generated using E91 protocol. Next, post-quantum cryptographic key encapsulation is applied to strengthened the generated kay and ensure long-term quantum resistance. Further, secret data is encrypted employing quantum-resilient encryption mechanism and combined using cryptographic hashing. Furthermore, encrypted data is embedded in to cover image through quantum-randomness-guided adaptive steganography for resisting improved steganalysis attacks. Finally, proposed QKD-PQC-ASE framework obtains improved resistance against future quantum attacks and enhanced steganalysis by maintaining low computational overhead. Therefore, proposed QKD-PQC-ASE framework achieved greater results in terms of NPCR of 99.84 % and a UACI of57.92%which demonstrates efficiency of framework for secure and future-ready data encryption in quantum-aware communication environments.
Quantum computing advances pose a serious threat to conventional public-key cryptographic systems such as RSA and elliptic curve cryptography as quantum algorithms may undermine the computational assumptions that guaranty their security. This challenge has driven the development of quantumsafe security approaches among which Quantum Key Distribution (QKD) represents a fundamentally different paradigm based on quantum mechanical principles rather than mathematical complexity. This paper presents a structured review of recent progress in QKD based on a systematic analysis of literature between 2020 and 2025, we examine core protocols including discrete-variable, continuous-variable, measurement-deviceindependent, and twin-field approaches, while also discussing their relationship with post-quantum cryptography as a complementary strategy for future secure communication systems. We provide a unified comparison framework to support practical design and policy decisions by organizing protocols and implementations along deployment dimensions. The study analyze theoretical foundations, implementation technologies across fiber, free-space, satellite, and integrated photonic platforms, and key performance trade-offs involving scalability, security robustness, and deployment feasibility. Findings indicate substantial progress in transitioning QKD from laboratory research toward practical implementations, supported by advances in network architectures, integrated hardware and hybrid cryptographic designs. The comparative analysis will highlight distinct strengths and limitations among protocol families and emphasize the potential of combining QKD with post-quantum cryptographic methods to enhance resilience. Remaining challenges including scalability constraints, implementation-level vulnerabilities, performance limitations over long distances, and integration with existing communication infrastructures are critically discussed. Finally, emerging research directions such as quantum repeaters, hybrid quantum-classical security models, and exploratory directions such as artificial intelligence-assisted optimizations are identified as key factors in enabling the evolution of QKD toward largescale quantum-secure networking.
This research introduces a novel cryptographic system that enhances the security of steganographic images by integrating Quantum Key Distribution (QKD) with traditional encryption. Using the E91 QKD protocol, it generates a shared secret key between parties, leveraging quantum entanglement to provide superior protection against eavesdropping. The quantum key is then hashed with the Secure Hash Algorithm (SHA) to produce a fixed-length, high-entropy key for symmetric encryption . The Advanced Encryption Standard (AES) is employed to encrypt steganographic images, which conceal critical data within digital images, adding an extra layer of security through obscurity. Experiments with images of varying resolutions (64 × 64 to 512 × 512 pixels) show consistent encryption performance. The encrypted images exhibit high randomness, with an average entropy of 7.9929. Differential attack resilience is demonstrated by a Number of Pixels Change Rate (NPCR) averaging 99.6928% and a Unified Average Changing Intensity (UACI) of 56.1549%. The average E91 protocol key generation time is 5.78 s with a key rate of 7.43 bps. Encryption and decryption times for test images are 0.00149 and 0.00175 s, respectively. This research combines quantum and classical cryptography with steganography, providing a robust security framework highly resistant to both quantum and classical threats.
Classical cryptography methods are becoming susceptible to quantum attacks like those implemented by Shor and Grover algorithms and can break RSA and symmetric-key encryption. Traditional communication channels are also susceptible to interception and even modification of the signal that causes data confidentiality to be compromised. In order to overcome these limitations, this paper proposes a three-layer quantum-hybrid communication framework, which integrates entanglement-based QKD, multi-channel redundancy, and steganographic hiding. The framework improves the security with an entanglement-assisted BB84-based protocol, the reliability with the help of multi-channel qubit transmission, and covert transmission with LSB/DCT-image embedding. The framework is developed and implemented as a simulator in Python using Qiskit, NumPy, and OpenCV and showed better Bit Error Rate (BER), SSIM, fidelity and security strength than classical systems. The proposed architecture mitigates key vulnerabilities in cryptographic strength, transmission stability, and communication detectability, providing a robust foundation for quantum-resilient and covert communication.
Modern information security measures have changed as a result of the quick development of quantum computing and communication technologies. As computing power increases, traditional steganography methods are more susceptible to quantum attacks. By using quantum mechanical features like superposition, entanglement, and quantum error-correcting algorithms to safely hide data, quantum steganography shows promise as a solution. Quantum steganography is an advanced cyber security method that offers full secrecy from either classical or quantum hacking. Using quantum-resistant methods for secure (biometric) transmission, anti-spoofing, and privacy-preserving authentication, this work presents a quantum steganography technique that expands upon the benefits of digital imaging's Novel Enhanced Quantum Representation (NEQR). Our research and testing have demonstrated that our method is secure against a variety of attacks and provides defense against present and potential dangers while preserving the steganography characteristics of capacity and imperceptibility, making it one of the greatest choices for transmitting confidential data.