With quantum computing nearing cryptographically relevant capabilities, classical file transfer systems face significant vulnerabilities, necessitating quantum-resistant solutions. This paper presents a hybrid architecture for secure file transfer, integrating a simulated BB84 quantum key distribution (QKD) protocol with adaptive encryption to achieve post-quantum security. The system intelligently selects one-time pad (OTP) cryptography for files up to 1MB, ensuring perfect secrecy, and AES-256-GCM for larger files, balancing efficiency and integrity, both using quantum-derived keys. Implemented in a TCP-based client-server framework, it employs a quantum key management module to maintain a pool of secure keys, with real-time error detection for eavesdropping. Experimental evaluation demonstrates robust key generation (error rate < 1% without eavesdropping, ~ 15% with interception), reliable encryption, and efficient transfers on standard hardware, eliminating the need for specialized quantum devices. This scalable, software-based solution advances quantum-enhanced protection for distributed file-sharing environments, addressing the urgent demand for practical post-quantum security.
With quantum computing nearing cryptographically relevant capabilities, classical file transfer systems face significant vulnerabilities, necessitating quantum-resistant solutions. This paper presents a hybrid architecture for secure file transfer, integrating a simulated BB84 quantum key distribution (QKD) protocol with adaptive encryption to achieve post-quantum security. The system intelligently selects one-time pad (OTP) cryptography for files up to 1MB, ensuring perfect secrecy, and AES-256-GCM for larger files, balancing efficiency and integrity, both using quantum-derived keys. Implemented in a TCP-based client-server framework, it employs a quantum key management module to maintain a pool of secure keys, with real-time error detection for eavesdropping. Experimental evaluation demonstrates robust key generation (error rate < 1% without eavesdropping, ~ 15% with interception), reliable encryption, and efficient transfers on standard hardware, eliminating the need for specialized quantum devices. This scalable, software-based solution advances quantum-enhanced protection for distributed file-sharing environments, addressing the urgent demand for practical post-quantum security.
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.
This paper presents the design, implementation, and evaluation of a hybrid encryption framework that combines quantum key distribution, specifically a simulated BB84 protocol, with AES-256 encryption. The system enables secure file encryption by leveraging quantum principles for key generation and classical cryptography for data protection. It introduces integrity validation mechanisms, including HMAC verification and optional post-quantum digital signatures, ensuring robustness even in the presence of quantum-capable adversaries. The entire architecture is implemented in Python, with modular components simulating quantum key exchange, encryption, and secure packaging. Experimental results include visual testing of various attack scenarios, such as key tampering, HMAC failure, and file corruption, demonstrating the effectiveness and resilience of the approach. The proposed solution serves as a practical foundation for quantum-aware cybersecurity systems.
Quantum computing is a significant risk to classical cryptographic, especially RSA, which depends on the difficulty of factoring large numbers. Classical factorization methods, such as Trial Division and Pollard's Rho, are inefficient for large keys, while Shor's quantum algorithm can break RSA efficiently in polynomial time. This research studies RSA's vulnerabilities under both classical and quantum attacks and designs a hybrid security framework to ensure data protection in the post-quantum era. The conceptual framework combines AES encryption for classical security, BB84 Quantum Key Distribution (QKD) for secure key exchange with eavesdropping detection, quantum state comparison for lightweight authentication, and a bio-inspired immune system for adaptive threat detection. RSA is vulnerable to Shor's algorithm, BB84 achieves full key agreement in ideal conditions, and it detects eavesdropping with high accuracy. The conceptual model includes both classical and quantum security methods, providing a scalable and adaptive solution for Post-Quantum encryption data protection. This work primarily proposes a conceptual framework. Detailed implementation, security proofs, and extensive experimental validation are considered future work.
Digital communication development creates an increasing threat to data security because emerging quantum computing technologies easily overcome traditional methods of encryption. A security system that integrates traditional encrypting with quantum computing methods shows promise for enhancing safety of networks mechanisms. The Hybrid Quantum Classical–Advanced Encryption System (HQC–AES) integrates the safe symmetrical functionality of the Advanced Encryption Standard (AES) with Quantum Key Distribution (QKD) procedures, specifically BB84 and E91, to ensure quantum resiliency. A secure key exchange together with real-time eavesdropper detection becomes possible through this combined approach, which maintains data confidentiality at a high level. A synthesis of post-quantum cryptography methods, such as Kyber and Falcon, safeguards traditional ways of communicating alongside quantum structures that lack comparability. The HQC–AES model provides solutions to three key cryptographic problems including secure key handling and distribution as well as encrypted transmission and long-term protection. Quantum mechanics enables protection enhancement for both conventional and quantum-based attacks by integrating it with advanced classical encryption methods. Theoretically, simulators and models show that the hybrid model maintains the technical agility of networks via several networked connections while simultaneously securing the reliability of data. The architecture delivers scalable security features to protect high-security cloud applications and financial systems and Internet of Things (IoT) resources by ensuring paramount secure communication capabilities. In safeguarding the transfer of data across several network circumstances, the suggested HQC–AES approach attained an overall accuracy of 98.7%. The fact that it is resistant to both conventional and quantum-based assaults and manages to keep data secure and intact is reflected in its excellent accuracy.
The accelerating development of quantum computing capabilities poses an unprecedented challenge to conventional encryption methodologies that currently underpin global digital security infrastructure. Classical cryptographic systems, including widely adopted standards such as RSA and AES, derive their security from the computational intractability of specific mathematical problems, a foundation that quantum algorithms threaten to fundamentally undermine. This research presents a comprehensive investigation into the practical implementation of Quantum Key Distribution as a transformative approach to establishing unconditionally secure communication channels. Through experimental deployment of the BB84 protocol augmented with advanced quantum error correction and privacy amplification techniques, we systematically evaluate the performance characteristics and security guarantees of QKD in realistic network environments. Our experimental framework achieves a secure key generation rate of 2.5 megabits per second while maintaining an average quantum bit error rate of 3.2 percent, demonstrating the practical viability of quantum-secured communication. The implementation exhibits exceptional eavesdropping detection capabilities with a 98.5 percent success rate in identifying unauthorized interception attempts. Comparative security analysis reveals that QKD-based encryption reduces vulnerability to brute-force attacks by 65 percent when contrasted with classical encryption standards. The integration of lattice-based post-quantum cryptographic algorithms provides an additional security layer against store-now-decrypt-later attack strategies. These findings substantiate the position of Quantum Key Distribution as a cornerstone technology for next-generation cybersecurity frameworks, offering robust protection against both current threats and the anticipated capabilities of large-scale quantum computers.