Abstract - In the emerging era of quantum computing, traditional cryptographic algorithms such as RSA and Elliptic Curve Cryptography (ECC) are at risk from quantum-based attacks. These developments pose a significant threat to secure network communication systems that rely on classical key exchange mechanisms. To overcome this challenge, the proposed work introduces a Hybrid Quantum-Resistant Key Exchange Protocol that combines the strengths of both classical andpost-quantum cryptographic algorithms. The hybrid approach integrates Elliptic Curve Dif ie–Hellman (ECDH) with alattice-based post-quantum algorithm, Kyber, to establish a shared session key between communicating entities. This sharedkeyisthen utilized for symmetric encryption using AES to ensure confidentiality and data integrity. The system is implementedusingPython socket programming to demonstrate secure data transmission between client and server. Performance is analyzedinterms of key generation time, encryption and decryption speed, key size, and computational ef iciency. The results validatethatthe proposed hybrid model provides enhanced resistance against quantum attacks while maintaining acceptable performance, making it suitable for future secure communication systems. Keywords - elliptic curve dif ie–hellman, hybrid key exchange, kyber, post-quantum cryptography, quantum computing.
Abstract - In the emerging era of quantum computing, traditional cryptographic algorithms such as RSA and Elliptic Curve Cryptography (ECC) are at risk from quantum-based attacks. These developments pose a significant threat to secure network communication systems that rely on classical key exchange mechanisms. To overcome this challenge, the proposed work introduces a Hybrid Quantum-Resistant Key Exchange Protocol that combines the strengths of both classical andpost-quantum cryptographic algorithms. The hybrid approach integrates Elliptic Curve Dif ie–Hellman (ECDH) with alattice-based post-quantum algorithm, Kyber, to establish a shared session key between communicating entities. This sharedkeyisthen utilized for symmetric encryption using AES to ensure confidentiality and data integrity. The system is implementedusingPython socket programming to demonstrate secure data transmission between client and server. Performance is analyzedinterms of key generation time, encryption and decryption speed, key size, and computational ef iciency. The results validatethatthe proposed hybrid model provides enhanced resistance against quantum attacks while maintaining acceptable performance, making it suitable for future secure communication systems. Keywords - elliptic curve dif ie–hellman, hybrid key exchange, kyber, post-quantum cryptography, quantum computing.
Quantum computing poses a growing challenge to conventional public-key cryptographic systems, particularly those relying on integer factorization and discrete logarithm problems. Widely deployed schemes such as RSA and elliptic curve cryptography are expected to become vulnerable as large-scale quantum computing capabilities emerge. This concern has intensified the demand for communication frameworks capable of maintaining long-term confidentiality in the presence of both classical and quantum-enabled adversaries. This paper presents a Hybrid Quantum-Resilient Key Exchange Algorithm (HKEA) that combines classical cryptographic mechanisms with lattice-based post-quantum cryptographic techniques to establish secure session keys. The proposed framework employs a dual-layer key establishment process in which classical and post-quantum shared secrets are integrated to generate a strengthened hybrid session key. The design aims to preserve compatibility with existing communication infrastructures while improving resistance to future quantum attacks and mitigating risks associated with Harvest-Now-Decrypt-Later (HNDL) threats. A prototype implementation was developed using Python-based cryptographic and post-quantum security libraries. The framework was evaluated using key generation time, latency, throughput, computational overhead, and security strength as performance indicators. Comparative analysis against conventional cryptographic approaches indicates that the proposed HKEA provides enhanced quantum resilience with only a modest increase in computational cost. The proposed approach offers a practical pathway toward secure and scalable communication systems for next-generation quantum-era network environments.
The rapid expansion of 5G wireless networks has introduced unprecedented security challenges, particularly in the face of emerging quantum computing threats. Traditional cryptographic schemes, including Elliptic Curve Cryptography (ECC), face vulnerabilities against quantum-based attacks, necessitating a transition toward quantum-resistant security solutions. A hybrid cryptographic framework incorporating CRYSTALS-Kyber for key encapsulation is proposed to mitigate these threats. CRYSTALS-Kyber, a lattice-based post-quantum cryptographic algorithm, enhances key exchange mechanisms by resisting quantum decryption attempts while maintaining computational efficiency. The proposed framework integrates CRYSTALS-Kyber with conventional ECC to establish a dual-layer security model that ensures backward compatibility while progressively adapting to quantum security standards. Simulation results demonstrate that the hybrid approach significantly enhances key exchange security while maintaining a low computational overhead. In particular, latency is reduced by 18.4% compared to standalone ECC-based key exchange, while key generation time improves by 22.7% due to CRYSTALS-Kyber’s efficient polynomial arithmetic operations. Furthermore, encryption throughput increases by 31.2%, demonstrating the model''s capability to secure high-speed 5G transmissions with minimal performance trade-offs.
The Hybrid approach in Quantum Cryptography creates adaptable security model which provides the safest Communication in the emerging quantum era. The development of quantum computing raise questions about the long-term security. Traditional algorithms, such as RSA, ECC, and Diffie-Hellman, which is seemed computationally secure but it can be effectively solved by quantum algorithms such as Shor's and Grover's. This problem leads to the origination of two key trends in current studies, namely Post-Quantum Cryptography (PQC), designing mathematical approaches to encryption resistant to quantum attacks; Quantum Key Distribution (QKD) using the principles of quantum mechanics to assure security in communications. Accordingly, this research proposes a hybrid security framework including reliable data encryption and authentication using PQC, combined with the safe key- exchange method of QKD. The model is implemented in Python, Qiskit, and PQClean's Kyber and Dilithium algorithms to show how these two paradigms can cooperate toward quantum- resilient communication. To present the system performance, key exchange efficiency, computational overhead, and security strength have been considered. According to the results, this hybrid approach gives superior defense against quantum threats while maintaining practical effectiveness for real-world applications such as cloud security, 6G networks, and the Internet of Things.
The rapid advancement of quantum computing poses a serious threat to traditional cryptographic systems such as RSA and Elliptic Curve Cryptography (ECC), which rely on computational difficulty for security. Quantum algorithms like Shor’s and Grover’s have the potential to break or weaken these methods, putting modern communication systems at risk. To address this challenge, this work presents a quantum-safe com-munication framework that combines the BB84 Quantum Key Distribution (QKD) protocol with Post-Quantum Cryptography (PQC) techniques, aiming to ensure secure data exchange in the presence of quantum-capable adversaries. In this system, the BB84 protocol is simulated to enable secure key exchange between two parties over a virtual quantum channel. The generated key is refined through processes such as basis matching, error correction, and privacy amplification using SHA-256 to ensure reliability and secrecy. For secur-ing communication, One-Time Pad (OTP) encryption is used alongside HMAC-SHA3-256 to provide both confidentiality and message integrity. Additionally, file encryption is handled using the XChaCha20-Poly1305 algorithm, selected for its efficiency and strong protection against potential vulnerabilities like nonce reuse. To further enhance security, the framework integrates a hybrid key management approach using the Kyber-512 Key Encapsulation Mechanism (KEM) combined with a Key Deriva-tion Function (KDF), merging classical and quantum-resistant techniques. Experimental results demonstrate the effectiveness of the system, achieving a Quantum Bit Error Rate (QBER) of 2.5% and successful performance in both message and file en-cryption. Overall, this work contributes toward the development of practical and resilient communication systems designed for the emerging quantum era.
The fast development of cyber communications, multimedia distribution, remote working have promoted the demand to transmit sensitive information through secure means in both the public and the private networks. The advent of massive quantum computers is rendering traditional cryptographic algorithms like RSA and Elliptic Curve Cryptography (ECC) insecure because they can crack the classical public-key algorithms like the Shor and Grover algorithms. This brings an immediate need of hybrid cryptographic systems, which integrate classical, quantum, and post-quantum algorithms to provide confidentiality, integrity, authentication, and future security beyond the quantum threat horizon.The paper is a proposal of a Hybrid Quantum-Post-Quantum Cryptographic Framework of transmitting files safely. It starts by aggregating files, which is a process to compress several files, images, videos, and multimedia files that users have chosen into one file to minimize redundancy and ease encryption. The AES-256 encrypted file is in GCM mode and provides confidentiality and integrity of the compressed file.The dual-layer mechanism ensures key establishment security. To begin with, Quantum Key Distribution (QKD) based on the protocols of BB84/E91 allows the Sender and the Receiver to generate a Quantum Secret Key (QSK) by exchanging quantum bits in quantum channel. Constant monitoring of the error rate facilitates automatic eavesdropping detection, and guarantees the keys generation is made when the conditions are secure, as well as the safeguarding of interception and man-in-the-middle attacks.A post-quantum layer is provided to ensure long-term security against quantum cryptanalysis, which uses Kyber, a NIST-approved lattice-based Key Encapsulation Mechanism (KEM). The Receiver creates a key pair of Kyber and disseminates the public key to the Sender. By using encapsulation, the Sender gets a PQC ciphertext and a Shared Secret (SS), with decapsulation on the Receiver side giving ensure that only participants of good faith get the same secret value.The hybridization phase consists of combining the QSK of QKD and SS of Kyber with the help of HKDF-SHA256 to obtain a Final Wrap Key (FWK). AES-GCM encrypts the key of file encryption by wrapping it with FWK which allows a secure and authenticated transfer of the key. The Sender sends four messages: encrypted file, Kyber ciphertext, wrapped AES key and the initialisation vector. At Receiver end, FWK is calculated once again with the help of QSK and SS so that the original data can be decrypted with the help of AES key.The suggested framework provides a defense-in-depth solution based on the combination of quantum security, post-quantum resilience and authenticated symmetric encryption. It can be analyzed that there is a strong resistance to classical and quantum adversaries, scalability, and compatibility with the existing communication networks. This renders the model to be appropriate to secure government communication, military systems, data exchange in healthcare environments, cloud storage and financial infrastructures. Keywords— Quantum Key Distribution (QKD), Post-Quantum Cryptography (PQC), Kyber,Key Encapsulation Mechanism (KEM), HKDF-SHA256, Quantum Secret Key (QSK), GCM Mode.
The digital age has ushered in a dependency on secure communication and data protection. Every day, vastamounts of sensitive information—ranging from personal data and financial transactions to governmentcommunications—are exchanged over networks. This security is largely ensured through modern cryptographicalgorithms that protect confidentiality, integrity, and authenticity. However, the emergence of quantumcomputing poses a significant threat to these systems, potentially rendering many classical cryptographictechniques obsolete. Quantum computers, leveraging the principles of quantum mechanics, have the theoreticalability to perform complex computations exponentially faster than classical computers. With the development ofquantum algorithms such as Shor’s algorithm and Grover’s algorithm, it becomes evident that once large-scalequantum computers become a reality, widely-used encryption schemes such as RSA, Elliptic CurveCryptography (ECC), and Diffie-Hellman may no longer be secure. Quantum-resistant cryptography, alsoknown as post-quantum cryptography, aims to develop cryptographic algorithms that are secure against bothclassical and quantum attacks. This project focuses on the study and analysis of quantum-resistant cryptographicalgorithms and presents the design, implementation, and evaluation of a Hybrid Post-Quantum TLS (PQ-TLS)framework. Experimental results demonstrate that the hybrid approach maintains efficient performance withsub-4-second response latencies and 100% data fidelity during encrypted transmission.