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.
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) 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.
This thesis explores the critical advancements in quantum communication with a primary focus on the BB84 protocol, the foundation of Quantum Key Distribution (QKD). It delves into the theoretical principles, practical implementation using Qiskit, and performance evaluation through metrics like entropy, Quantum Bit Error Rate (QBER), and efficiency. Comparative analysis with alternative protocols, such as B92 and SARG04, highlights their advantages, limitations, and suitability for real-world applications. The work also addresses challenges like photon number splitting attacks and implementation imperfections, contributing to the development of robust quantum cryptographic systems. By bridging theory and practice, the thesis emphasizes the transformative potential of quantum cryptography in securing communication against both classical and quantum threats. This comprehensive study paves the way for advancements in secure, scalable quantum communication technologies.
As digital communication continues to scale globally, cybersecurity vulnerabilities are becoming increasingly sophisticated. Classical encryption methods—based on mathematical complexity—face obsolescence with the advancement of quantum computing, which can break widely used cryptosystems such as RSA and ECC through algorithms like Shor’s. Quantum Key Distribution (QKD) represents a paradigm shift by leveraging the laws of quantum mechanics, particularly photon entanglement and Heisenberg’s uncertainty principle, to establish secure communication channels. Unlike classical cryptography, which relies on computational security, QKD guarantees information-theoretic security, making interception detectable and ineffective. This research paper evaluates entanglement-based protocols, including E91, BBM92, and emerging satellite-assisted QKD networks. The study includes a comparative performance analysis between classical cryptographic techniques and QKD across speed, security breach probability, latency, and scalability. A real-world case study of China’s Micius Quantum Satellite Network is used to illustrate practical deployment. Findings show that QKD reduces key interception vulnerability to near zero, while classical systems remain susceptible to brute-force and eavesdropping attacks. Data demonstrate that entanglement-based QKD outperforms other quantum protocols in long distance secure communication and offers a scalable foundation for the future quantum internet.
Quantum Key Distribution (QKD) provides an innovative approach for secure communication by utilizing the principles of quantum mechanics. Among various QKD protocols, the BB84 protocol remains the most widely studied and implemented due to its simplicity and theoretical security guarantees. However, practical implementations of BB84 are vulnerable to several eavesdropping attacks and channel imperfections. This paper presents a comprehensive study on the detection and analysis of eavesdropping attacks in the BB84 protocol. The work focuses on common attacks such as intercept-resend attack, photon-number splitting attack, Trojan horse attack, and phase-covariant cloning attack. The effect of these attacks on Quantum Bit Error Rate (QBER) is analyzed in detail. Simulation-based observations are discussed to demonstrate how QBER increases under malicious interference. The study further explores statistical methods for detecting eavesdropping and examines practical countermeasures including decoy states, privacy amplification, and error correction techniques. The paper concludes that BB84 remains robust against eavesdropping when proper detection and mitigation mechanisms are employed.
Quantum Key Distribution (QKD) protocols offer a revolutionary approach to secure communication, leveraging the principles of quantum mechanics to enable theoretically unbreakable encryption. This comprehensive review examines the security and efficiency of various QKD protocols, including BB84, E91, and Continuous Variable QKD. We analyze the fundamental principles underpinning these protocols, their implementation challenges, and the practical considerations for real-world deployment. Special emphasis is placed on the security proofs of QKD, addressing potential vulnerabilities such as photon number splitting attacks and detector blinding attacks. Additionally, we explore the efficiency of QKD systems in terms of key generation rates, distance limitations, and integration with existing communication infrastructures. Recent advancements in QKD technology, including satellite-based QKD and quantum repeaters, are also discussed. Our findings highlight the critical role of QKD in future-proofing communication security and the ongoing efforts to enhance its practicality and scalability. This review aims to provide a detailed understanding of the current state of QKD protocols, offering insights into their potential to transform secure communications in the quantum era.
Against the backdrop where traditional cryptosystems are threatened by algorithms such as Shor and Grover, Quantum Key Distribution (QKD) technology serves as a next-generation security technology. However, the diversity of its protocols poses challenges to practical research, development, and application. This paper adopts a literature review approach to systematically classify the principles, characteristics, and application scenarios of mainstream protocols, including BB84, SARG04, and MDI-QKD, and also conducts a horizontal comparison of the differences between these protocols in terms of physical implementation, security, key rate, and anti-attack capability. The comparative study reveals that each type of protocol has its own advantages and disadvantages. For instance, BB84 needs to address transmission loss, SARG04 can resist Photon Number Splitting (PNS) attacks, and MDI-QKD is immune to measurement device attacks. Nevertheless, it is still necessary to select a protocol with high adaptability based on factors such as transmission distance, light source type, and environmental noise. This research lays a foundation for the practical application of QKD technology.