ABSTRACT In recent years, Quantum Key Distribution (QKD) has experienced rapid advancements, leading to widespread practical applications and drawing considerable attention from both academic and commercial sectors. Consequently, there has also been a growing interest in investigating the performance and efficiency of various QKD protocols. In this tutorial paper, we present a theoretical simulation‐based review of several QKD protocols, such as BB84, Decoy State BB84, Coherent One Way (COW), Differential Phase Shift (DPS), and the entanglement‐based BBM92 and E91 protocols. We simulate the Quantum Bit Error Rate (QBER) and Secret Key Rate (SKR) under varying parameters to provide a deeper understanding of their performance and inner workings. In addition to the simulation results, we introduce a web‐based graphical user interface (GUI) that allows users to interactively explore protocol behaviour and visualise the impact of various system parameters on the QBER and SKR of the QKD protocols. This tutorial aims to offer an intuitive understanding of various QKD protocols from an engineering perspective, using accessible simulation and visual analysis tools.
ABSTRACT In recent years, Quantum Key Distribution (QKD) has experienced rapid advancements, leading to widespread practical applications and drawing considerable attention from both academic and commercial sectors. Consequently, there has also been a growing interest in investigating the performance and efficiency of various QKD protocols. In this tutorial paper, we present a theoretical simulation‐based review of several QKD protocols, such as BB84, Decoy State BB84, Coherent One Way (COW), Differential Phase Shift (DPS), and the entanglement‐based BBM92 and E91 protocols. We simulate the Quantum Bit Error Rate (QBER) and Secret Key Rate (SKR) under varying parameters to provide a deeper understanding of their performance and inner workings. In addition to the simulation results, we introduce a web‐based graphical user interface (GUI) that allows users to interactively explore protocol behaviour and visualise the impact of various system parameters on the QBER and SKR of the QKD protocols. This tutorial aims to offer an intuitive understanding of various QKD protocols from an engineering perspective, using accessible simulation and visual analysis tools.
Quantum computing is advancing rapidly and thus is a major challenge to traditional schemes of cryptographies like RSA, and ECC that get their security on computational difficulty. In order to counter this challenge, a paradigm change to be proposed is quantum cryptography which is based on the application of the rules of quantum mechanics to a conditional security. In the paper, a design and implementation of an interactive simulation platform, which models two seminal quantum key distribution (QKD) protocols, namely, BB84 and E91, is proposed. Formulated with a modular architecture in Streamlit, the system allows users to simulate the transmission into qubit, visualize key pre-processing, study the quantum bit error rate (QBER) and detect any eavesdropping through CHSH inequality. The platform will be used to include functionality of real-time graphical dashboards, user authentication, and a comparative analysis segment to systematically review classical and quantum-related cryptographic methods. The effects of noise levels, adversarial interference on the QBER and key generation rates are verified, and this serves to confirm the resilience of quantum systems against eavesdropping. The tool can be used as an educational and a research tool since it offers an intuitive interface to learn the quantum concepts related to superposition or entanglement and simultaneously takes the user through the protocol functionality in different security regimes. The findings attest to the increased security capabilities of quantum cryptographic systems, thus making them a valid option in the future communication network during the post-quantum era.
Quantum Key Distribution (QKD) is a technique that enables secure communication between two parties by sharing a secret key. One of the most well-known QKD protocols is the BB84 protocol, proposed by Charles Bennett and Gilles Brassard in 1984. In this protocol, Alice and Bob use a quantum channel to exchange qubits, allowing them to generate a shared key that is resistant to eavesdropping. This paper presents a comparative study of existing QKD schemes, including the BB84 protocol, and highlights the advancements made in the BB84 protocol over the years. The study aims to provide a comprehensive overview of the different QKD schemes and their strengths and weaknesses and demonstrate QKDs working principles through existing simulations and implementations. Through this study, we show that the BB84 protocol is a highly secure QKD scheme that has been extensively studied and implemented in various settings. Furthermore, we discuss the improvements made to the BB84 protocol to enhance its security and practicality, including the use of decoy states and advanced error correction techniques. Overall, this paper provides a comprehensive analysis of QKD schemes, focusing on the BB84 protocol in secure communication technologies.
The demand for security is growing exponentially in every field of developing technology. Over the decades, classical and modern cryptographic algorithms have served this need with an appreciable performance. But with the realization of threats to this backbone cryptography, researchers have developed a keen interest in Quantum cryptography(QC). QC provides an unconditionally secure means of information transfer through the basic laws of quantum mechanics. Quantum key distribution(QKD) is one of the most developed application of QC. But due to primitive technology it is still facing many developmental glitches. Although there is a fare amount of QKD experimentation available, the experiments are limited with specific set of parameters. To observe the effect of parameter variation it is essential to model the QKD process. This paper discusses the simulation approach for understanding and testing the working of practical prepare and measure QKD protocol. The developed model is tested with the experimental test data from three QKD setups. Performance parameters such as quantum bit error rate and secret key rate are analyzed. It is observed that the simulated results matches with the experimental results.
Quantum Key Distribution is a leading-edge cryptographic technology that influences the fundamentals of physics quantum mechanics to enable the secure exchange of encryption keys, establishing peerless levels of confidentiality and aversion against eavesdropping. Quantum Key Distribution (QKD) protocols have been hinged on proceeding in the field of quantum cryptography, guaranteeing safer communication in the existence of adversaries. This paper lays out the comparative survey of some important QKD protocols which are BB84, E91, TF, CV, MDI, COW DPS and SARG04. Each protocol has its unique advantages, characteristics, and limitations, making them appropriate for their different deployment environmental areas. BB84 works on the principle of polarization state and E91 works on entanglement. Both are good at providing robust security under various attack models. To overcome the distance limitations of traditional QKD protocols Twin-Field protocol is a way better that attain more advanced performance in long-distance communication. In Continuous Variable QKD, the requirement of detectors turns out to be lower at the practical levels. Trusted detectors are abolished in MDI-QKD, intensifying the security against the detector side-channel attacks. Coherent One-Way QKD powers up the key rates by employing the encoding in time-bin and phase coherence. Differential Phase Shift-QKD targeted on differential phase shifts for providing robustness against definite types of attack. Finally, Photon number splitting (PNS) attacks get resistance from the SARG04 QKD protocol making it more secure way in a practical framework. In this paper, we compare the performances of these protocols in terms of key rates, error tolerance, security, implementation challenges, advantages, limitations, and feasibility in the real world that are offering perception into their capability for future quantum communication networks.
Abstract An experimental Quantum Key Distribution (QKD) implementation requires advanced costly hardware, unavailable in most research environments, making protocol testing and performance evaluation complicated. This has been a major motivation for the development of QKD simulation frameworks, to allow researchers to obtain insight before proceeding into practical implementations. Several simulators have been introduced over the recent years. However, only four are publicly available, only one of which models equipment imperfections. Currently, no open‐source simulator includes all following capabilities: channel attenuation modelling, equipment imperfections and effects on key rates, estimation of elapsed time during classical and quantum‐ channel processes, use of truly random binary sequences for qubits and measurement bases, shared ‐bit fraction customization. In this paper, we present NuQKD, an open‐ source modular, intuitive simulator, featuring all the above capabilities. NuQKD establishes communication between two computer terminals, accepts custom user inputs (iterations, raw key size, attacker interception rate etc.) and evaluates the sifted key, Quantum Bit Error Rate (QBER), elapsed communication time, and more. NuQKD capabilities include optical fiber and free ‐space simulation, modeling of equipment/channel imperfections, bitstrings from True Random Number Generators, decoy‐state protocol support, and automated evaluation of performance metrics. We expect NuQKD to enable convenient and accurate representation of actual experimental conditions.
Quantum Key Distribution (QKD) is one of the most promising technologies that enable theoretically unbreakable secure communications in this highly advanced information security era. This work provides a comparative analysis of QKD protocols such as BB84, Coherent One-Way (COW), and Differential Phase-Shift (DPS) against eavesdropping attacks e.g., Photon Number Splitting (PNS) attack. It employs a realistic approach to simulations such as using weak coherent pulse (WCP) sources. This work also explores qubit generation and the whole key distribution process in non-ideal conditions. Detailed algorithms have been discussed that simulate the encoding, transmission, and decoding process for every protocol, as well as simulating PNS attacks where an eavesdropper removes photons to gain key information without any detectable errors. Statistical metrics, such as Visibility and the information gain, are used to quantify the impact of these attacks. Future work aspects may include the extension of the simulation to incorporate additional parameters such as channel noise, fiber attenuation, detector dark counts, etc. to provide a realistic analysis to compare various QKD protocols.