Quantum Key Distribution (QKD) is a potential defense against future quantum attacks that can break traditional encryption algorithms, such as RSA and ECC. The current work is based on the development of the BB84 protocol with the features of utilizing quantum mechanics and eavesdropping detection through signal disturbance. A simulation of the BB84 protocol was built using polarization encoding over a 10 km single-mode optical fiber using OptiSystem software. The system consists of standard telecom equipment, such as a continuous wave laser at a frequency of 193.1 THz, polarization controllers, and single-photon detectors. Both secure and insecure cases were simulated, where an attacker (Eve) had used an intercept-resend attack. The outcome showed significant Bit Error Rate (BER) and Quantum Bit Error Rate (QBER) increases during attacks, thus proving the protocol's vulnerability to interference. In addition, a special intrusion detection system based on BER was used to identify such anomalies in real-time. The simulation illustrates the feasibility of using QKD in today's optical networks to secure communications.
Quantum Key Distribution (QKD) is a potential defense against future quantum attacks that can break traditional encryption algorithms, such as RSA and ECC. The current work is based on the development of the BB84 protocol with the features of utilizing quantum mechanics and eavesdropping detection through signal disturbance. A simulation of the BB84 protocol was built using polarization encoding over a 10 km single-mode optical fiber using OptiSystem software. The system consists of standard telecom equipment, such as a continuous wave laser at a frequency of 193.1 THz, polarization controllers, and single-photon detectors. Both secure and insecure cases were simulated, where an attacker (Eve) had used an intercept-resend attack. The outcome showed significant Bit Error Rate (BER) and Quantum Bit Error Rate (QBER) increases during attacks, thus proving the protocol's vulnerability to interference. In addition, a special intrusion detection system based on BER was used to identify such anomalies in real-time. The simulation illustrates the feasibility of using QKD in today's optical networks to secure communications.
Quantum Key Distribution (QKD) is increasingly recognized as a robust solution to the vulnerabilities posed by quantum computing to classical encryption systems. This paper presents a comprehensive investigation of the BB84 protocol, the foundational QKD scheme, through simulated quantum communication using IBM’s Qiskit framework. The study models quantum key exchange under both ideal and adversarial conditions, including channel noise and intercept-resend attacks. The Quantum Bit Error Rate (QBER) was measured as a function of noise intensity and eavesdropping, confirming that QBER increases predictably in compromised channels. A threshold of 11% QBER was used to determine the viability of secure key generation. Final key retention rates were analyzed across multiple channel scenarios, revealing BB84’s sensitivity to both photon loss and adversarial interference.\n\nSecurity vulnerabilities such as photon-number-splitting and detector blinding were assessed, and countermeasures including decoy-state protocols and authenticated classical channels were proposed. Four key performance graphs were generated to visualize system behavior under realistic operational conditions. The results support BB84’s theoretical advantage in ensuring information-theoretic security while acknowledging real-world limitations in transmission range and hardware reliability. The paper concludes by addressing future improvements in QKD systems, including satellite-based distribution, quantum repeaters, and device-independent implementations. Through simulation-driven analysis, this study validates BB84 as a practical defense against quantum-enabled attacks and underscores the need for continued development and standardization in post-quantum cryptographic infrastructure.
Abstract As quantum computing continues to demonstrate its potential to break through existing cryptographic systems, quantum key distribution (QKD) provides a novel approach to protect communications in the post-quantum era, but presents complex challenges in terms of research and widespread adoption. Although the resource-intensive nature of QKD setups limits experimental studies to specialized laboratories, we present an end-to-end simulation that models photon generation, transmission, and detection, thereby lowering the barrier to testing hypotheses regarding experimental setups under realistic conditions. In this study, a fiber optic-based simulation was utilized along with a quantum circuit and a detailed noise model within the BB84 protocol to recreate an experimental setup. Our BB84 simulation retained ≈50% of transmitted bits after sifting, matching the experimental expectations, and produced quantum bit error rate (QBER) values that rose with increasing channel length. Our model incorporates customizable noise, such as multi-photon emissions and channel disturbances, directly into the key exchange process, yielding QBER values of ≈4.5% at 20 km and ≈11% at 120 km, consistent with physical systems under the same conditions. Our findings support the development of QKD as a scalable solution for securing the quantum internet and future communication networks.
As quantum computing threatens classical cryptography like RSA via Shor's algorithm, Quantum Key Distribution (QKD)—especially BB84—offers physics-based security. BB84 leverages quantum principles: Heisenberg Uncertainty, No-Cloning Theorem, and superposition, shifting from math complexity to unbreakable physical laws using polarized photons for key exchange. The protocol detects eavesdropping through Quantum Bit Error Rate (QBER), showing 25% errors in Intercept-Resend attacks. Key challenges like Photon Number Splitting (PNS) attacks are addressed via decoy states. Compared to B92 and E91, BB84 balances feasibility and security best. Despite issues like signal loss, BB84 provides provably secure communication, restoring trust in a post-quantum world.
Quantum key distribution (QKD) has been developed within the last decade that is provably secure against arbitrary computing power, and even against quantum computer attacks. Now there is a strong need of research to exploit this technology in the existing communication networks. In this paper we have presented various experimental results pertaining to QKD like Raw key rate and Quantum bit error rate (QBER). We found these results over 25 km single mode optical fiber. The experimental setup implemented the enhanced version of BB84 QKD protocol. Based upon the results obtained, we have presented a network design which can be implemented for the realization of large scale QKD networks. Furthermore, several new ideas are presented and discussed to integrate the QKD technique in the classical communication networks.
As quantum computing threatens to compromise classical cryptographic systems, the need for future-proof, information-theoretically secure methods of communication has become critical. Quantum Key Distribution (QKD) leverages the fundamental principles of quantum mechanics to enable the secure generation and exchange of encryption keys, immune to computational attacks. This paper investigates the integration of QKD into telecom infrastructures to enable ultra-secure communication. We examine the performance of key QKD protocols, such as BB84 and E91, over fiber-optic and free-space channels, and simulate their deployment within realistic metropolitan network topologies. Results show that secure key rates of up to 10 kbps can be maintained over 50–80 km fiber links with Quantum Bit Error Rates (QBER) below 5%. The study also explores architecture models based on trusted relay nodes and WDM coexistence, highlighting practical deployment considerations. Our findings suggest that QKD is a viable enhancement for telecom security and a necessary foundation for long-term quantum-resilient communication systems.
Quantum computers threaten current secure communication methods, prompting the emergence of new ideas to ensure communication resistant to this threat. Quantum Key Distribution (QKD) is one such technology leveraging quantum physics for secure symmetric key distribution. We, therefore, present an experimental setup with accompanying programs for initialization, calibration, and data processing designed for implementing QKD based on the BB84 protocol, using lasers at wavelengths of 810 nm. In our approach, Alice and Bob do not need to have synchronized watches nor share a synchronizing signal: their alignment in time is achieved by minimization of the bit error rate (BER). The protocol has been successfully executed at up to 8.3 dB loss, equivalent to 2.7 km of G.652.D telecom fiber, commonly used in current communications. Achieved BER is 1.0% at 0.7 dB loss and rises to 1.7% for 8.3 dB loss. While usual QKD solutions prefer expensive IR components and detectors in the telecom wavelength range, our study shows the viability of using affordable near-infrared (NIR) optics and silicon SPAD-based detectors for shorter distances.