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IEEE Access

A Novel Approach Based on Quantum Key Distribution Using BB84 and E91 Protocol for Resilient Encryption and Eavesdropper Detection

Noor Ul Ain, Muhammad Waqar, Anas Bilal, Ajung Kim, Haider Ali, Umair Ullah Tariq, Muhammad Shahroz Nadeem

Published Jan 1, 2025• 43 citations
Publisher

Abstract

Quantum cryptography is anticipated to drive substantial advancements in cybersecurity. The impending arrival of quantum cryptography compromises current encryption methods, possibly compromising the effectiveness of traditional key management-based security protocols. One fundamental Quantum Key Distribution (QKD) protocol, BB84, encounters challenges when operating with fewer Quantum bits (Qubits) and bases that only support up to 8 Qubits. This limitation weakens the system’s security, making brute force, intercept, and resend attacks less challenging. Consequently, this study proposes a method to enhance the security of the BB84 protocol, to reduce susceptibility to attacks and eavesdropping. The improved BB84 protocol utilizes 9, 12, and 16 quantum bits along with two, and three bases to significantly bolster security. This allows authorized parties to eliminate the use of compromised keys. Additionally, the study implements the E91 QKD protocol utilizing the Entanglement Pair Generation (EPR) method to produce secure keys. While the existing E91 protocol ensures security through Bell’s theorem and Bell’s inequality, it overlooks the impact of noise, leading to inaccuracies in eavesdropper detection. To address this, the study introduces an additional security measure. Whenever an eavesdropper attempts to measure the quantum state, the proposed E91 protocol collapses its state from$\vert 10\rangle $to$\vert 11\rangle $, setting the first Qubit to$\vert 1\rangle $and the other Qubit to$\vert 0\rangle $, thus providing the eavesdropper with incorrect information, accompanied by a phase angle of$15\pi $/8. This leads to a misconception, preventing eavesdroppers from obtaining useful details about transferred quantum states. Additionally, considering that the proposed E91 protocol relies on entangled particles and utilizes double Qubit gates, which are inherently noisier than single Qubit gates and more susceptible to quantum decoherence, this study employs error mitigation techniques during the final measurement to predict outcomes more efficiently.

DOI
10.1109/access.2025.3539178

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Quantum cryptography is anticipated to drive substantial advancements in cybersecurity. The impending arrival of quantum cryptography compromises current encryption methods, possibly compromising the effectiveness of traditional key management-based security protocols. One fundamental Quantum Key Distribution (QKD) protocol, BB84, encounters challenges when operating with fewer Quantum bits (Qubits) and bases that only support up to 8 Qubits. This limitation weakens the system’s security, making brute force, intercept, and resend attacks less challenging. Consequently, this study proposes a method to enhance the security of the BB84 protocol, to reduce susceptibility to attacks and eavesdropping. The improved BB84 protocol utilizes 9, 12, and 16 quantum bits along with two, and three bases to significantly bolster security. This allows authorized parties to eliminate the use of compromised keys. Additionally, the study implements the E91 QKD protocol utilizing the Entanglement Pair Generation (EPR) method to produce secure keys. While the existing E91 protocol ensures security through Bell’s theorem and Bell’s inequality, it overlooks the impact of noise, leading to inaccuracies in eavesdropper detection. To address this, the study introduces an additional security measure. Whenever an eavesdropper attempts to measure the quantum state, the proposed E91 protocol collapses its state from∣10⟩\vert 10\rangle ∣10⟩to∣11⟩\vert 11\rangle ∣11⟩, setting the first Qubit to∣1⟩\vert 1\rangle ∣1⟩and the other Qubit to∣0⟩\vert 0\rangle ∣0⟩, thus providing the eavesdropper with incorrect information, accompanied by a phase angle of15π15\pi 15π/8. This leads to a misconception, preventing eavesdroppers from obtaining useful details about transferred quantum states. Additionally, considering that the proposed E91 protocol relies on entangled particles and utilizes double Qubit gates, which are inherently noisier than single Qubit gates and more susceptible to quantum decoherence, this study employs error mitigation techniques during the final measurement to predict outcomes more efficiently.
Quantum Key Distribution (QKD) is a ground-breaking solution to secure communication that uses fundamental quantum mechanics principles to allow for the exchange of cryptographic keys with provable security. BB84 and E91, two of the first and most significant QKD systems, presented two different approaches to using quantum characteristics to prevent eavesdropping and maintain confidentiality. A brief literature review of these two fundamental protocols is presented in this paper. Bennett and Brassard created the BB84 protocol in 1984. It uses polarized photons and detects interception using the uncertainty principle. On the other hand, Bell's theorem and entangled photon pairs are used in the E91 protocol, which was first presented by Ekert in 1991, to guarantee the integrity of the shared key. Each protocol's theoretical foundations, methods of implementation, and relative benefits has been explored in addition to how they have influenced contemporary quantum cryptography systems. This paper attempts to give a basic understanding of QKD and its early advancements by examining the similarities and differences between BB84 and E91.
Quantum Key Distribution (QKD) is a ground-breaking solution to secure communication that uses fundamental quantum mechanics principles to allow for the exchange of cryptographic keys with provable security. BB84 and E91, two of the first and most significant QKD systems, presented two different approaches to using quantum characteristics to prevent eavesdropping and maintain confidentiality. A brief literature review of these two fundamental protocols is presented in this paper. Bennett and Brassard created the BB84 protocol in 1984. It uses polarized photons and detects interception using the uncertainty principle. On the other hand, Bell's theorem and entangled photon pairs are used in the E91 protocol, which was first presented by Ekert in 1991, to guarantee the integrity of the shared key. Each protocol's theoretical foundations, methods of implementation, and relative benefits has been explored in addition to how they have influenced contemporary quantum cryptography systems. This paper attempts to give a basic understanding of QKD and its early advancements by examining the similarities and differences between BB84 and E91.
Current communication systems predominantly operate using classical bits, with security mechanisms grounded in traditional cryptographic techniques. These conventional methods rely on the computational difficulty of discrete mathematical problems, which are expected to be vulnerable in the emerging quantum era. The advent of quantum computing poses a significant threat to existing cryptographic protocols, as quantum algorithms can potentially break schemes once considered computationally intractable. This scenario has accelerated interest in quantum cryptography, an advanced paradigm that leverages the fundamental laws of quantum mechanics to ensure secure data transmission. Quantum cryptography, and in particular Quantum Key Distribution (QKD), offers a robust alternative to classical key exchange methods. Unlike classical schemes, QKD’s security is rooted in the physical properties of quantum states, making it immune to computational advancements, including those offered by quantum computers. Among the various QKD protocols, the E91 protocol, based on quantum entanglement, demonstrates significant potential for enhancing communication security and resilience against cyber-attacks. This study investigates the role of quantum cryptography in safeguarding data transfer, with a specific focus on the E91 QKD protocol. It explores the operational principles, security advantages, and practical considerations of E91 in the context of evolving cybersecurity threats. By providing a detailed examination of E91’s implementation and performance, this research contributes novel insights into its feasibility as a cornerstone technology for building secure communication frameworks in the post-quantum era.
Quantum Key Distribution (QKD) brings a revolutionary approach to secure communication by using the principles of quantum mechanics to safeguard the transfer of cryptographic keys.This project explores the practical deployment of two foundational QKD protocols: BB84 and E91.The BB84 protocol secures key distribution through photon polarization, while the E91 protocol uses the unique properties of quantum entanglement to enhance resistance to eavesdropping.By contrasting these quantum methods with classical cryptographic techniques, the study provides a comprehensive look at their relative strengths and limitations.Practical implementation and thorough analysis demonstrate that QKD protocols offer significant advantages in preventing interception, shedding light on their potential role in advancing cryptographic security in the era of quantum technology.This research not only assesses the practical challenges of implementing QKD but also considers future advancements that could broaden its real-world applications.
Quantum key distribution (QKD) allows two spatially separated parties to securely generate a cryptographic key. The first QKD protocol, published by C. H. Bennett and G. Brassard in 1984 (BB84), describes how this is achieved by transmitting individual qubits and exchanging classical authenticated information. Any attempt to eavesdrop on the protocol introduces errors detectable by the legitimate parties. This Licentiate Thesis studies the recently introduced EEQKD protocol which builds on BB84. In EEQKD, the qubits sent individually in BB84 are entangled and thus not directly available to an eavesdropper who is, in this protocol, provided only one-by-one access to the transmission. The maximal information an eavesdropper can gain using a straightforward intercept-resend (IR) attack, is obtained for a given error rate. The secure key generation rate of EEQKD is estimated in practical scenarios including qubit loss and quantum channel noise. In addition, an exquisite vulnerability is exposed: For a particular setting of qubit entanglement, paradoxically proving most useful in the face of an IR attack, EEQKD reduces to BB84. Part of this research has been published in O. Ahonen et al., Physical Review A 78, 032314 (2008).
Abstract This paper investigates practical performances of the Ekert 91 protocol (E91) for future secure quantum networks. To seek future possible improvement, we investigate the important different principles of E91 and Bennet-Brasard (BB84) protocols. We perform a series of computer simulations to evaluate the performances of them and investigate the practical parameters. Furthermore, we simulate the E91 protocol using real-world practical scenarios involving eavesdropping and quantum channel errors. We present two scenarios: (1) the performance with eavesdropper interception under a perfect channel and (2) the performances with eavesdropper interception combined with channel errors. We found that: (i) the E91 protocol produces fewer keys compared to the BB84 protocol but does not require verification between two parties, (ii) the E91 protocol enhances security due to the utilization of Clauser, Horne, Shimony, and Holt (CHSH) inequality, and (iii) both eavesdropper and channel errors can impact the less production of keys obtained during the keys production.