Abstract The current paper presents a quantum-classical cryptographic protocol, which is a hybrid of the BB84 Quantum Key Distribution (QKD) protocol and a lattice-based post-quantum signature scheme, CRYSTALS-Dilithium. Such a mix is to create a safe channel of communication that is resistant to classical and quantum assaults. The protocol relies on the unconditional security of QKD to exchange keys in a symmetric way and addresses the vulnerability of QKD to man-in-the-middle (MitM) attacks by strong classical authentication provided by PQC signatures. Another important invention of this work is the ever-refreshing of the keys. This is to enable the periodic updating of the session key without necessarily having to undergo the entire re-authentication two-way handshake. This is enhanced to improve forward secrecy and reduce the computational requirements. To demonstrate the viability and security aspects of the protocol, we give a theoretical framework and a simulation of the protocol by IBMs Qiskit. The protocol showed that it was able to generate secure keys successfully which was in line with the theoretical expectations. The embedded CRYSTALS-Dilithium signature provides effective authentication that ensures that the hybrid system is viable and does not cause any performance problem. The simulation results quantitatively validate the protocol's security and performance, demonstrating a QBER of 0.7% under ideal conditions, which is well below the 25% abort threshold. These findings indicate that this mixed solution is an effective solution to secure long-term communications in the quantum age.
Abstract The current paper presents a quantum-classical cryptographic protocol, which is a hybrid of the BB84 Quantum Key Distribution (QKD) protocol and a lattice-based post-quantum signature scheme, CRYSTALS-Dilithium. Such a mix is to create a safe channel of communication that is resistant to classical and quantum assaults. The protocol relies on the unconditional security of QKD to exchange keys in a symmetric way and addresses the vulnerability of QKD to man-in-the-middle (MitM) attacks by strong classical authentication provided by PQC signatures. Another important invention of this work is the ever-refreshing of the keys. This is to enable the periodic updating of the session key without necessarily having to undergo the entire re-authentication two-way handshake. This is enhanced to improve forward secrecy and reduce the computational requirements. To demonstrate the viability and security aspects of the protocol, we give a theoretical framework and a simulation of the protocol by IBMs Qiskit. The protocol showed that it was able to generate secure keys successfully which was in line with the theoretical expectations. The embedded CRYSTALS-Dilithium signature provides effective authentication that ensures that the hybrid system is viable and does not cause any performance problem. The simulation results quantitatively validate the protocol's security and performance, demonstrating a QBER of 0.7% under ideal conditions, which is well below the 25% abort threshold. These findings indicate that this mixed solution is an effective solution to secure long-term communications in the quantum age.
Quantum computing threatens traditional cryptographic systems based on integer factorization and discrete logarithm problems. This paper proposes a hybrid secure communication framework integrating Quantum Key Distribution (QKD) with Post-Quantum Cryptography (PQC) for authentication. The BB84 protocol is used for quantum key generation, while CRYSTALS-Dilithium signatures secure the classical communication channel. A Python-based simulator models photon transmission, Quantum Bit Error Rate (QBER), intercept-resend attacks, and authentication verification. Results show that QBER increases proportionally with eavesdropping probability, enabling reliable attack detection. The integration of QKD secrecy with PQC authentication ensures both confidentiality and integrity. Performance evaluation demonstrates that the additional latency introduced by PQC authentication remains within acceptable limits. The proposed hybrid framework provides a scalable and quantum-resistant solution suitable for next-generation secure communication systems.
Quantum computing threatens traditional cryptographic systems based on integer factorization and discrete logarithm problems. This paper proposes a hybrid secure communication framework integrating Quantum Key Distribution (QKD) with Post-Quantum Cryptography (PQC) for authentication. The BB84 protocol is used for quantum key generation, while CRYSTALS-Dilithium signatures secure the classical communication channel. A Python-based simulator models photon transmission, Quantum Bit Error Rate (QBER), intercept-resend attacks, and authentication verification. Results show that QBER increases proportionally with eavesdropping probability, enabling reliable attack detection. The integration of QKD secrecy with PQC authentication ensures both confidentiality and integrity. Performance evaluation demonstrates that the additional latency introduced by PQC authentication remains within acceptable limits. The proposed hybrid framework provides a scalable and quantum-resistant solution suitable for next-generation secure communication systems.
With the rise of quantum computing, traditional encryption methods like RSA and ECC are increasingly vulnerable to quantum attacks. This paper presents Qryptic, a secure messaging platform designed to withstand such threats through the integration of Quantum Key Distribution (QKD) and Post-Quantum Cryptography (PQC). Using the BB84 protocol for QKD and Crystals-Dilithium for digital signatures, the system ensures quantum-resilient key exchanges and authentication. Additionally, AES-256 provides efficient end-to-end encryption, with session keys derived securely from the distributed quantum keys, enabling forward secrecy.A unique aspect of Qryptic is its QR-based QKD handshake for secure user connection, alongside a custom Qryptic Phrase Code (QPC) that replaces traditional usernames for added security. The system architecture includes real-time key refresh mechanisms, cryptographic session isolation, and attack resistance to both classical and quantum adversaries.Through a hybrid cryptographic model and rigorous testing against threats like Grover’s and Shor’s attacks, Qryptic demonstrates strong performance, usability, and future-proof security. This paper details the system design, implementation, and evaluation, contributing to the development of scalable, post-quantum secure communication systems for the coming quantum era.
Large quantum computers will be able to break the cryptographic algorithms on which current secure communications rely on. Post-Quantum Cryptography (PQC) and Quantum key distribution (QKD) are two security technologies that show protection capabilities against the latent quantum threat. While PQC relies on different hard mathematical problems to develop a wide variety of cryptographic operations, QKD is based on quantum physics laws to generate and distribute symmetric cryptographic keys through different QKD protocols. These keys can be used by different applications to perform security transformations. QKD still requires authentication to prevent man-in-the-middle attacks. The hybridization of PQC and QKD is an important step for future secure infrastructures, being able to provide long-term security. In this work we propose authenticated QKD approaches that rely on pre-shared keys and hybrid PQC/QKD alternatives and which are able to securely exchange secret QKD keys through authenticated channels. We identify the different configuration alternatives and their parameters, as well as we develop a wide performance evaluation. Results show that pre-shared keys and PQC-based authentication through Dilithium algorithm are the fastest alternatives. Also, we show the potential of the T12 QKD protocol.
The high pace of quantum computing development presents a serious risk to classical cryptographic systems like RSA and ECC in that quantum-resilient communication systems must be developed. The present paper will suggest Quantum Blind Signature-based Hybrid Quantum Key Distribution (QKD -QBS) to provide secure and authenticated quantum communication. The proposed architecture uses both BB84 and Decoy-State QKD protocols with Quantum Blind Signature (QBS) authentication layer in order to support quantum key generation and verification of entities in the same session. The framework is simulated and tested with IBM Qiskit Aer simulator in realistic channel noise situations. Quantum Bit Error Rate (QBER), Secret Key Retention (SKR), Quantum Entropy (H), Authentication Latency and Security Index (SI) are used as performance evaluation metrics. The experimental data show that the QBER is low (0.34%), SKR is high (92.4%), entropy is nearly ideal (H=0.99) with the lowest authentication latency (0.17 ms), which proves the fact that the integration of QBS does not reduce the efficiency of the key generation but the reliability of authentication. The hybrid framework proposed has information-theoretic security using the principles of quantum mechanics and strong resistance to impersonation, re-play and man in the middle attacks. The findings show that QKDQBS model provides a scalable and solid platform of next generation secure communication systems, such as IoT,5G/6Gnetworks, and cloud-based quantum systems.
The emergence of large-scale quantum computers poses a significant threat to current cryptographic protocols, particularly Transport Layer Security (TLS), which relies on RSA and elliptic curve cryptography vulnerable to Shor's algorithm. This paper presents a hybrid framework for quantum-resistant TLS handshakes that integrates post-quantum cryptography (PQC), quantum key distribution (QKD) and classical cryptography to provide comprehensive protection against both classical and quantum attacks. The approach employs three QKD protocols; BB84, E91, and Measurement-Device-Independent QKD (MDI-QKD) alongside NIST-standardized PQC algorithms as well as alternative candidates such as HQC and BIKE. A key innovation is the QKD key management module, which addresses performance bottlenecks through periodic key generation and secure reuse within predefined retention periods, significantly reducing QKD overhead in TLS handshakes. The experimental implementation using the quantum network simulator evaluated 144 distinct cryptographic protocol combinations. Results demonstrate that ML-KEM combined with ML-DSA provides optimal PQC performance, while QKD protocol selection is distance-dependent: BB84 for short-range and MDI-QKD for long-distance communication. The framework includes various attack mitigation mechanisms and ensure security as long as at least one cryptographic method remains uncompromised. Consistent with current global quantum network usage, the proposed TLS approach is designed primarily for MAN and WAN environments rather than the Internet, providing a balanced solution that combines theoretical security guarantees with computational efficiency.