Quantum key distribution (QKD) provides a foundation for information-theoretic security based on quantum mechanics, yet its practical deployment is often constrained by intrinsically low secure key generation rates, particularly in high-bandwidth or low-latency settings. This work introduces a hybrid cryptographic technique that integrates conventional QKD with deterministic chaos, modeled using the Lorenz attractor, to provide a software-based enhancement of the effective key expansion rate. From a short 20-bit QKD seed, the system generates long bitstreams within milliseconds; although these streams exhibit high empirical randomness, their fundamental entropy remains bounded by the seed, consistent with standard cryptographic principles. The method employs the exponential divergence of chaotic trajectories, such that even minute uncertainties in an adversary's estimate of the initial state lead to rapid desynchronization and, as established in Appendix A, an exponential decay of Eve's mutual information with respect to the expanded key. Simulation results confirm this theoretical behavior and demonstrate an effective rate amplification exceeding two orders of magnitude over the baseline QKD seed rate. The proposed chaotic expansion operates entirely in software and requires no modifications to existing QKD hardware, offering a practical pathway to enhance throughput for applications ranging from secure video communication to low-latency IoT and edge-computing environments.
Quantum key distribution (QKD) provides a foundation for information-theoretic security based on quantum mechanics, yet its practical deployment is often constrained by intrinsically low secure key generation rates, particularly in high-bandwidth or low-latency settings. This work introduces a hybrid cryptographic technique that integrates conventional QKD with deterministic chaos, modeled using the Lorenz attractor, to provide a software-based enhancement of the effective key expansion rate. From a short 20-bit QKD seed, the system generates long bitstreams within milliseconds; although these streams exhibit high empirical randomness, their fundamental entropy remains bounded by the seed, consistent with standard cryptographic principles. The method employs the exponential divergence of chaotic trajectories, such that even minute uncertainties in an adversary's estimate of the initial state lead to rapid desynchronization and, as established in Appendix A, an exponential decay of Eve's mutual information with respect to the expanded key. Simulation results confirm this theoretical behavior and demonstrate an effective rate amplification exceeding two orders of magnitude over the baseline QKD seed rate. The proposed chaotic expansion operates entirely in software and requires no modifications to existing QKD hardware, offering a practical pathway to enhance throughput for applications ranging from secure video communication to low-latency IoT and edge-computing environments.
Secure cryptographic key distribution is one of the essential conditions of modern protection of digital communications. The rise of large-scale quantum computing is a very real threat to traditional public-key cryptosystems, with the most commonly used cryptosystems, including RSA and elliptic curve cryptography, being easily broken with the help of quantum algorithms. Despite the demonstrable security offered by Quantum Key Distribution (QKD) through the laws of quantum mechanics, it has a limited range of transmission, expensive hardware, and it is difficult to scale. In order to overcome these shortcomings, this paper will propose a Hybrid Quantum-Classical Key Distribution (HQCKD) framework that combines quantum key generation and classical key management schemes. The proposed solution uses QKD to create a short and very safe quantum key seed, which then scalable classical cryptographic protocols based on long distance and large scale communication are booted up. The frames are tested by means of simulation in real network conditions, the latency, throughput, and security resilience are assessed. It is experimentally proven that the suggested hybrid model attains low end-to-end latency and high scalability with high resistance to both classical and quantum adversaries. The HQCKD framework is much simpler to implement and significantly less expensive in terms of infrastructure and deployment compared to bare QKD systems, which means that it is a realistic and future-proof approach to post-quantum safe communication.
Quantum key distribution (QKD) promises unconditionally secure communications, however, the low bit rate of QKD cannot meet the requirements of high-speed applications. Despite the many solutions that have been proposed in recent years, they are neither efficient to generate the secret keys nor compatible with other QKD systems. This paper, based on chaotic cryptography and middleware technology, proposes an efficient and universal QKD protocol that can be directly deployed on top of any existing QKD system without modifying the underlying QKD protocol and optical platform. It initially takes the bit string generated by the QKD system as input, periodically updates the chaotic system, and efficiently outputs the bit sequences. Theoretical analysis and simulation results demonstrate that our protocol can efficiently increase the bit rate of the QKD system as well as securely generate bit sequences with perfect statistical properties. Compared with the existing methods, our protocol is more efficient and universal, it can be rapidly deployed on the QKD system to increase the bit rate when the QKD system becomes the bottleneck of its communication system.
The exponential growth of the Internet of Things (IoT) and its integration into critical infrastructures has elevated the need for robust and future-proof security mechanisms. Traditional cryptographic systems, while effective today, are increasingly vulnerable to advancements in quantum computing. This paper explores the integration of Quantum Key Distribution (QKD) as a novel security paradigm for next-generation IoT ecosystems. QKD leverages the principles of quantum mechanics to enable unconditionally secure key exchange, immune to computational attacks. We propose an architecture where QKD-enabled edge gateways and IoT nodes facilitate real-time secure communication through quantum-secured channels. The study analyzes the feasibility of implementing QKD in resource-constrained IoT environments and evaluates its performance in terms of key generation rate, latency, and energy consumption. Simulation results demonstrate that the proposed QKD-IoT framework significantly outperforms conventional encryption protocols in resisting both classical and quantum-based attacks, making it a viable foundation for building post-quantum resilient IoT infrastructures. The research also outlines the challenges related to scalability, hardware integration, and key management, and proposes solutions through hybrid QKD-classical cryptography models. This work paves the way for a quantum-secure IoT future, ensuring trust, privacy, and integrity in hyper-connected digital ecosystems.
Quantum Key Distribution (QKD) represents a revolutionary advancement in secure communication. It leverages principles of quantum mechanics to establish cryptographic keys between parties with theoretically unbreakable security. Among the various QKD protocols, BB84 (Bennett and Brassard, 1984) and Twin-Field QKD are prominent due to their foundational simplicity and advanced key generation efficiency, respectively. The BB84 protocol, as the first QKD protocol, uses quantum bits (qubits) in different bases to securely generate shared keys, while Twin-Field QKD enhances the key generation rate by exploiting quantum interference between distant entangled states, making it more suitable for long-distance communication. This work explores the integration of BB84 and Twin-Field QKD into a hybrid algorithm, aiming at combining the robustness of BB84 with the high key generation rate and entropy of Twin-Field QKD. The hybrid algorithm alternates between the two protocols, leveraging their individual strengths to optimize key generation performance. Simulation results indicate that the hybrid algorithm can effectively balance the robustness and simplicity of BB84 with the high efficiency and entropy of Twin-Field QKD. Specifically, the hybrid algorithm demonstrated an error rate of 8.9%, a key generation rate of 50%, and an entropy of 0.999 bits, which outperforms the compared algorithms.
Secure communication has become essential due to the rapid increase in cyber-attacks and data security threats in modern networks. Traditional communication systems mainly rely on classical security methods, which may become vulnerable to advanced attacks. Quantum Key Distribution (QKD) improves secure communication by generating cryptographic keys using quantum principles, making key interception extremely difficult. In this work, a Quantum Random Number Generator (QRNG) is integrated with classical communication to develop a hybrid quantum-classical communication framework. The QRNG generates highly random bits that improve authentication, randomness, and key security. The proposed system compares three QKD protocols: BB84, B92, and E91 using different bit sizes of 8000, 10000, and 13000 bits. The protocols are evaluated using important metrics such as QBER, key rate, entropy, erasure rate, throughput, and correlation. Experimental results show that all protocols achieved entropy values close to 1 and correlation values near zero, indicating strong randomness and secure key generation. Among the evaluated protocols, E91 achieved lower QBER values and higher key rates, while BB84 showed stable and reliable performance. B92 produced comparatively higher error rates under similar conditions. The throughput remained nearly 278–281 bits/sec across all experiments. A ranking-based analysis confirmed that E91 provides the best balance between security, efficiency, and communication performance, making it suitable for future quantum-secure communication systems.
The emergence of quantum computing poses a significant threat to classical cryptographic systems, particularly those relying on mathematical hardness assumptions for key exchange. While symmetric algorithms such as the Advanced Encryption Standard (AES) remain efficient and widely deployed, their long-term security ultimately depends on the secrecy of keys. In this paper, we present a hybrid framework that integrates quantum key distribution (QKD) with AES and DES to enhance key security without altering cipher internals. Using the BB84 protocol as the quantum key generator, we implement a simulation-based system in Qiskit and evaluate it against classical pseudo-random key generation.Our methodology covers five phases: establishing AES/DES baselines, generating quantum random keys, implementing BB84 with basis reconciliation and error detection, integrating quantum keys with AES/DES, and benchmarking across varying key sizes and file sizes. Results demonstrate that AES encryption throughput remains stable (around 250–370 MB/s) regardless of key source, while QKD introduces measurable latency in key generation (around 40–110 seconds for 128–256 bits). Importantly, adversarial interference is reliably detected, with 97.3% accuracy in eavesdropper identification.The findings confirm that while classical systems excel in speed and scalability, QKD offers unmatched, physics-backed security assurances. Our study highlights the practicality of hybrid quantum-classical encryption, providing a foundation for secure communication in the post-quantum era.