Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:2410.21191

Improving BB84 Efficiency with Delayed Measurement via Quantum Memory

Mohammed Th. Hassan, Omar Abouelazm

Published Oct 28, 2024• 0 citations
arXivHTMLPDF

Abstract

In this paper, we introduce a novel modification to the BB84 Quantum Key Distribution (QKD) protocol, aimed at enhancing its efficiency through the use of quantum memory and delayed measurement. In the standard BB84 protocol, the receiver immediately measures the qubits sent by the sender using randomly chosen bases. Due to mismatches between the sender and receiver's bases, a significant portion of the qubits are discarded, reducing the overall key generation rate. Our proposed protocol allows the receiver to store the received qubits in quantum memory and defer measurement until after the sender reveals her basis choices, effectively eliminating the need to discard mismatched qubits. This modification improves the key generation efficiency while maintaining the core security features of the standard BB84 protocol. By avoiding the unnecessary loss of qubits, our protocol achieves a higher secret key rate without introducing additional vulnerabilities. We present a detailed step-by-step explanation of the delayed measurement process. Although this approach does not alter the security guarantees of BB84, it represents a significant improvement in efficiency, making the protocol more viable for large-scale quantum communication networks.

DOI
10.48550/arxiv.2410.21191

Related papers

Efficient Quantum Key Distribution Using Balanced Incomplete Block Designs

Abdelhalim Houssaoui, Otmane El Mouaatamid, Mostafa Belkasmi

Quantum Key Distribution (QKD) is a critical technology for secure communication in the quantum era, with the BB84 protocol being one of the most widely adopted methods for sharing secret keys. However, random qubit distribution in the BB84 protocol presents challenges, such as inefficient qubit usage, higher error rates, and potential security vulnerabilities. This paper introduces a Efficient Quantum Key Distribution Using Balanced Incomplete Block Designs (BIBD) to optimize qubit distribution. By leveraging BIBD properties, the scheme achieves more efficient and balanced qubit allocation, enhancing security by increasing the key generation rate and improving resistance to eavesdropping attacks. Theoretical analysis and simulation results show that this scheme enhances scalability and key generation rates while maintaining robust security guarantees, making it suitable for large-scale quantum communication systems.

International Conference on Advanced Communication Technologies and Networking (CommNet)•Dec 4, 2024•1 citation

Advanced Secure Communication: Exploring Quantum Key Distribution, the BB84 Method

Badukuri Hemalatha, Badukuri Premalatha, B. Reddaiah

One promising way to use quantum information to secure everyday communication is through the distribution of quantum keys. By exchanging a secret key, the Quantum Key Distribution (QKD) approach allows two parties to communicate securely.BB84 protocol is among the most well-known QKD protocols. In this protocol, qubits are exchanged via a quantum channel between the sender and the receiver. This enables them to produce a shared key that is impenetrable to eavesdroppers and illustrate the fundamental ideas of QKD using current simulations and implementations. The results of this study demonstrate that the BB84 protocol is a highly secure QKD technique that has been investigated in great detail and used in a variety of contexts. Additionally, over the enhancements made to the BB84 protocol such as the use of advanced error correction techniques and decoy states to increase its security and usability is discussed. With an emphasis on the BB84 protocol in secure communication technologies, this study offers an extensive analysis of QKD systems overall.

International Journal of Engineering and Advanced Technology•Apr 21, 2024•0 citations

Enhanced BB84 Quantum Key Distribution Protocol with Index-Based Qubit Tagging and Correction Method

Ramya Jothikumar, S Varun Krishna, K Bharanidharan +1 more

Quantum Key Distribution (QKD) leverages quantum mechanical principles to establish information-theoretically secure cryptographic keys. The cornerstone BB84 protocol, however, suffers from key rate degradation due to the mandatory discarding of erroneous bits during post-processing. This paper presents an enhanced BB84 protocol incorporating a Tagging and Correction Method that systematically tracks, classifies, and corrects errors rather than discarding them. This approach maximizes the key material retained from the quantum transmission. The protocol integrates decoy state analysis for robust detection of photon-number-splitting (PNS) attacks and concludes with privacy amplification to ensure informationtheoretic security. Experimental validation using a high-fidelity Qiskit simulation with a realistic depolarizing channel model demonstrates a significant improvement in key rate efficiency. In a simulated environment with 15% eavesdropper intervention, our method achieved a 7.8% higher key rate than standard BB84, while successfully maintaining the Quantum Bit Error Rate (QBER) below the 11% security threshold. This work establishes a more robust and efficient framework for practical QKD implementations.

•Oct 22, 2025•0 citations

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 +4 more

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.

IEEE Access•Jan 1, 2025•43 citations

PaQKD: Optimizing Qubit Retention in Quantum Key Distribution Using Packeting

Romir G. Sharma, Winston W. Wang

Quantum Key Delivery (QKD) enables next generation cryptography, which is able to remain secure past the advent of quantum supremacy. Current protocols such as BB84 enable sharing private keys using properties of qubits, and allow users to check for eavesdroppers. However, these protocols suffer from low qubit retention rates, requiring up to four times the key length of potentially expensive qubits to be sent. Additionally, if an eavesdropper is detected, the entire key must be discarded. In this paper, we propose an improvement to the BB84 protocol, a packeting based protocol called PaQKD. PaQKD uses periodic checks in order to catch eavesdroppers during the process instead of only checking at the end of transmission, enabling users preserve a partial key. Simulations show that PaQKD significantly improves qubit retention rate as well, whether an eavesdropper is present or not, with insignificant loss of detection.

IEEE MIT Undergraduate Research Technology Conference (URTC)•Oct 6, 2023•0 citations

Improved source-correlated quantum key distribution

Siying LI, ZHU Shun, Feifei Hu +5 more

Based on the basic principles of quantum mechanics, quantum key distribution (QKD) provides unconditional security for long-distance communication. However, existing QKD with relevant source protocols have limited tolerance for source correlation, which greatly reduces the key generation rate and limits the secure transmission distance, thereby limiting their practical deployment. In this work, we propose an improved QKD with correlated source protocol to overcome these limitations by discarding the traditional loss-tolerant security frameworks. Our approach adopts the standard BB84 protocol for the security analysis, under the assumption that the source correlation has a bounded range and characterized inner product of the states. We theoretically analyze the performance of the improved protocol at different levels of source correlation and channel loss. Numerical simulations show that our protocol achieves a much higher secret key rate and longer transmission distance than traditional schemes. In the case of typical parameters and 0 dB loss, our protocol achieves about 1.5–3 times improvement in secret key rate. Additionally, the maximum tolerable loss is enhanced by about 2–6 dB. This highlights a promising direction for enhancing the robustness and practicality of QKD with correlated sources systems, paving the way for their deployment in real-world quantum communication networks.

Acta Physica Sinica•Jan 1, 2025•0 citations
In this paper, we introduce a novel modification to the BB84 Quantum Key Distribution (QKD) protocol, aimed at enhancing its efficiency through the use of quantum memory and delayed measurement. In the standard BB84 protocol, the receiver immediately measures the qubits sent by the sender using randomly chosen bases. Due to mismatches between the sender and receiver's bases, a significant portion of the qubits are discarded, reducing the overall key generation rate. Our proposed protocol allows the receiver to store the received qubits in quantum memory and defer measurement until after the sender reveals her basis choices, effectively eliminating the need to discard mismatched qubits. This modification improves the key generation efficiency while maintaining the core security features of the standard BB84 protocol. By avoiding the unnecessary loss of qubits, our protocol achieves a higher secret key rate without introducing additional vulnerabilities. We present a detailed step-by-step explanation of the delayed measurement process. Although this approach does not alter the security guarantees of BB84, it represents a significant improvement in efficiency, making the protocol more viable for large-scale quantum communication networks.
Quantum Key Distribution (QKD) is a critical technology for secure communication in the quantum era, with the BB84 protocol being one of the most widely adopted methods for sharing secret keys. However, random qubit distribution in the BB84 protocol presents challenges, such as inefficient qubit usage, higher error rates, and potential security vulnerabilities. This paper introduces a Efficient Quantum Key Distribution Using Balanced Incomplete Block Designs (BIBD) to optimize qubit distribution. By leveraging BIBD properties, the scheme achieves more efficient and balanced qubit allocation, enhancing security by increasing the key generation rate and improving resistance to eavesdropping attacks. Theoretical analysis and simulation results show that this scheme enhances scalability and key generation rates while maintaining robust security guarantees, making it suitable for large-scale quantum communication systems.
One promising way to use quantum information to secure everyday communication is through the distribution of quantum keys. By exchanging a secret key, the Quantum Key Distribution (QKD) approach allows two parties to communicate securely.BB84 protocol is among the most well-known QKD protocols. In this protocol, qubits are exchanged via a quantum channel between the sender and the receiver. This enables them to produce a shared key that is impenetrable to eavesdroppers and illustrate the fundamental ideas of QKD using current simulations and implementations. The results of this study demonstrate that the BB84 protocol is a highly secure QKD technique that has been investigated in great detail and used in a variety of contexts. Additionally, over the enhancements made to the BB84 protocol such as the use of advanced error correction techniques and decoy states to increase its security and usability is discussed. With an emphasis on the BB84 protocol in secure communication technologies, this study offers an extensive analysis of QKD systems overall.
Quantum Key Distribution (QKD) leverages quantum mechanical principles to establish information-theoretically secure cryptographic keys. The cornerstone BB84 protocol, however, suffers from key rate degradation due to the mandatory discarding of erroneous bits during post-processing. This paper presents an enhanced BB84 protocol incorporating a Tagging and Correction Method that systematically tracks, classifies, and corrects errors rather than discarding them. This approach maximizes the key material retained from the quantum transmission. The protocol integrates decoy state analysis for robust detection of photon-number-splitting (PNS) attacks and concludes with privacy amplification to ensure informationtheoretic security. Experimental validation using a high-fidelity Qiskit simulation with a realistic depolarizing channel model demonstrates a significant improvement in key rate efficiency. In a simulated environment with 15% eavesdropper intervention, our method achieved a 7.8% higher key rate than standard BB84, while successfully maintaining the Quantum Bit Error Rate (QBER) below the 11% security threshold. This work establishes a more robust and efficient framework for practical QKD implementations.
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 tototo\vert 11\rangle ,settingthefirstQubitto, setting the first Qubit to,settingthefirstQubitto\vert 1\rangle andtheotherQubittoand the other Qubit toandtheotherQubitto\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.
Quantum Key Delivery (QKD) enables next generation cryptography, which is able to remain secure past the advent of quantum supremacy. Current protocols such as BB84 enable sharing private keys using properties of qubits, and allow users to check for eavesdroppers. However, these protocols suffer from low qubit retention rates, requiring up to four times the key length of potentially expensive qubits to be sent. Additionally, if an eavesdropper is detected, the entire key must be discarded. In this paper, we propose an improvement to the BB84 protocol, a packeting based protocol called PaQKD. PaQKD uses periodic checks in order to catch eavesdroppers during the process instead of only checking at the end of transmission, enabling users preserve a partial key. Simulations show that PaQKD significantly improves qubit retention rate as well, whether an eavesdropper is present or not, with insignificant loss of detection.
Based on the basic principles of quantum mechanics, quantum key distribution (QKD) provides unconditional security for long-distance communication. However, existing QKD with relevant source protocols have limited tolerance for source correlation, which greatly reduces the key generation rate and limits the secure transmission distance, thereby limiting their practical deployment. In this work, we propose an improved QKD with correlated source protocol to overcome these limitations by discarding the traditional loss-tolerant security frameworks. Our approach adopts the standard BB84 protocol for the security analysis, under the assumption that the source correlation has a bounded range and characterized inner product of the states. We theoretically analyze the performance of the improved protocol at different levels of source correlation and channel loss. Numerical simulations show that our protocol achieves a much higher secret key rate and longer transmission distance than traditional schemes. In the case of typical parameters and 0 dB loss, our protocol achieves about 1.5–3 times improvement in secret key rate. Additionally, the maximum tolerable loss is enhanced by about 2–6 dB. This highlights a promising direction for enhancing the robustness and practicality of QKD with correlated sources systems, paving the way for their deployment in real-world quantum communication networks.