The rapid progress of quantum computing demands secure communication protocols which are beyond classical cryptographic techniques. This necessity of Quantum Key Distribution (QKD) is met by providing security relying on the fundamental laws of quantum mechanics. In the work presented, the BB84 protocol is implemented using Qiskit platform provided by IBM. The performance is analyzed for both the ideal channel conditions and an intercept–resend eavesdropping scenario studying its security behavior and performance. 100% key agreement is observed with a QBER of 0% for the BB84 protocol executed under the ideal condition. When an eavesdropper is introduced, the QBER increases significantly, ranging from 16% to 38%, exceeding the acceptable security threshold of 11% and resulting in complete rejection of the generated key. Performance analysis carried out for key sizes between 100 and 1000 qubits shows that the execution time follows O(n) trend growing linearly. This simulation validates the correct operation of the BB84 protocol and demonstrates a detailed performance and security analysis of a QKD system using IBM Qiskit.
The rapid progress of quantum computing demands secure communication protocols which are beyond classical cryptographic techniques. This necessity of Quantum Key Distribution (QKD) is met by providing security relying on the fundamental laws of quantum mechanics. In the work presented, the BB84 protocol is implemented using Qiskit platform provided by IBM. The performance is analyzed for both the ideal channel conditions and an intercept–resend eavesdropping scenario studying its security behavior and performance. 100% key agreement is observed with a QBER of 0% for the BB84 protocol executed under the ideal condition. When an eavesdropper is introduced, the QBER increases significantly, ranging from 16% to 38%, exceeding the acceptable security threshold of 11% and resulting in complete rejection of the generated key. Performance analysis carried out for key sizes between 100 and 1000 qubits shows that the execution time follows O(n) trend growing linearly. This simulation validates the correct operation of the BB84 protocol and demonstrates a detailed performance and security analysis of a QKD system using IBM Qiskit.
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.
Quantum Key Distribution (QKD) offers a revolutionary method for secure key exchange by exploiting the principles of quantum mechanics. This paper comprehensively reviews the pioneering BB84 protocol, its experimental realization using IBM's Qiskit framework, and the underlying quantum computing concepts. We detail the methodology including qubit encoding, measurement, basis reconciliation, and key sifting, and discuss performance metrics such as the Quantum Bit Error Rate (QBER) and key generation rate. Experimental results obtained on IBM Quantum hardware are presented and analyzed, highlighting the robustness of the protocol and its security implications. The review underscores the importance of integrating QKD with future-proof encryption schemes in a quantum-enabled era.
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.
The rapid advancement of quantum computing poses a significant threat to classical cryptographic systems that form the backbone of modern digital security.Algorithms such as RSA and ECC, which rely on the computational difficulty of integer factorization and discrete logarithm problems, become vulnerable to quantum attacks, particularly Shor's algorithm.This project presents a comprehensive Quantum Key Distribution (QKD) Simulator that implements the BB84 and E91 protocols using IBM's Qiskit quantum computing framework, providing an interactive platform for understanding, simulating, and analyzing quantum-safe key exchange mechanisms.The simulator features a full-stack architecture with a FastAPI backend powered by Python and Qiskit for quantum circuit execution, and a React 19 frontend with TypeScript for interactive visualization.The BB84 protocol implementation supports configurable qubit counts, multiple measurement bases (Z, X, and Diagonal), Eve's intercept-resend attack simulation with adjustable interception rates, and Quantum Bit Error Rate (QBER) calculation with a security threshold of 8.5%.The E91 protocol implementation uses entangled Bell state pairs with configurable measurement angles, CHSH inequality violation testing for quantum security verification, and reverse gate anti-eavesdropping mechanisms.Additionally, the system includes an AES encryption module that uses quantum-generated keys from BB84 and E91 simulations to perform AES-128, AES-192, and AES-256 encryption, with privacy amplification for keys shorter than the required length.A simulation history system with SQLite and PostgreSQL support enables experiment tracking, comparison, and analysis.The project demonstrates the practical application of quantum mechanics principles to cryptographic security and serves as an educational tool for understanding the transition from classical to quantum-safe cryptography.
Quantum computing poses significant threats to conventional cryptographic techniques such as RSA and AES, motivating the need for quantum secure communication methods. Quantum Key Distribution (QKD) offers information theoretic security based on fundamental quantum principles. This paper presents a simulation-based analysis of well-known QKD protocols, namely BB84, B92, and E91, using the IBM Qiskit framework. Realistic quantum channel effects, including noise, decoherence, and eavesdropping, are modeled to evaluate protocol performance. Key metrics such as error rate, secret key generation, and security characteristics are analyzed and compared. The study highlights practical challenges in QKD implementation, including hardware limitations and channel losses, and discusses insights toward scalable and robust quantum communication systems. The results support the feasibility of QKD as a promising solution for secure communication in the quantum era.
Abstract Secure military communications depend on the confidentiality of exchanged cryptographic keys across command centers, satellite links, and classified order transmission. Classical key-distribution protocols rely on computational hardness assumptions that provide no intrinsic mechanism for detecting interception; an adversary who copies transmitted ciphertext leaves no physical trace. Quantum Key Distribution (QKD), and specifically the BB84 protocol, replaces this assumption with a physical guarantee derived from quantum mechanics: any attempt to measure an unknown quantum state necessarily disturbs it, rendering interception statistically detectable. This study implements the BB84 protocol at the circuit level — qubit state preparation, basis selection, interception modeling, and measurement — and validates its central security property, the Quantum Bit Error Rate (QBER) signature of eavesdropping, in two stages: (1) a noiseless statevector simulation using the PKTron quantum computing framework over ten independent trials per condition, and (2) hardware execution on IBM Quantum's ibm_fez superconducting processor. In simulation, the average QBER without an eavesdropper was 0.000, and with a full intercept-resend attack was 0.248, closely matching the theoretical prediction of 0.25. On real hardware, the undisturbed channel returned QBER = 0.000 (19 sifted bits) and the eavesdropped channel returned QBER = 0.261 (23 sifted bits), in close agreement with both theory and the simulated baseline. These results provide a reproducible, two-platform validation of the eavesdropper-detection mechanism that underlies the security claims made for QKD-protected communications. This study validates the cryptographic detection primitive only; it does not constitute a deployed secure communications system, and extending these results to operational command, satellite, or classified-order channels requires physical single-photon transmission hardware, authenticated classical channels, and full key-management infrastructure outside the scope of this work.