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

International Conference on Ubiquitous and Future Networks

Efficient Reconciliation Protocol with Polar Codes for Quantum Key Distribution

Sunghoon Lee, Jun Heo

Published Jul 1, 2018• 12 citations
Publisher

Abstract

Information reconciliation is a critical process of any Quantum Key Distribution (QKD) protocol, where two legitimate parties agree on a secret key. Two parties attempt to eliminate the discrepancies between their correlated keys in the presence of an adversary, while revealing a minimum amount of information. In this paper, we propose a reconciliation protocol using polar codes with a soft-output decoder. We demonstrate that our method is better than a conventional protocol using polar codes in the view of reconciliation efficiency.

DOI
10.1109/icufn.2018.8436787

Related papers

Evaluation of adaptive reconciliation protocols for CV-QKD using systematic polar codes

Meixiang Zhang, Qiang Wang, Thara Son +1 more

Abstract Quantum key distribution (QKD) is a secure cryptographic technology that enables two authenticated parties to share secret keys. Information reconciliation is an essential step in continuous-variable quantum key distribution (CV-QKD) protocols, which affects both the complexity and performance of the system. This paper reviews adaptive reconciliation protocols, and also proposes a new efficient scheme using systematic polar codes. Simulation results show that the proposed scheme can significantly increase reconciliation efficiency and reduce the overall computational complexity by reducing the average number of retransmissions, without significant reduction in effective secret key length.

Quantum Information Processing•Apr 23, 2024•8 citations

Reconciliation with polar codes constructed using Gaussian approximation for long-distance continuous-variable quantum key distribution

Yongseen Kim, Changho Suh, June‐Koo Kevin Rhee

Quantum key distribution (QKD) enables two authenticated parties to share secret keys with the ability to detect any attempts to eavesdrop the keys theoretically. Currently, QKD systems can be categorized by its source of uncertainty in nature; single photon or coherent light. As coherent light is harnessed, the overall cost for composing systems drops in general. However, more elaborate post processing is required to extract and share errorless secret keys. Such process is called reconciliation, which is critical to performance. To extend the maximum distance to distill secret keys and prevent it from being bottleneck, we propose a reconciliation protocol that combines multidimensional reconciliation and polar codes. Especially, considering some practical issues, Gaussian approximation is chosen to construct polar codes. The simulation results show that the proposed protocol can support decent performance of coherent-light-based systems at long distance with reduced complexity.

International Conference on Information and Communication Technology Convergence (ICTC)•Oct 1, 2017•4 citations

Improved reconciliation with polar codes in quantum key distribution

Sunghoon Lee, Joo Youn Park, Jun Heo

Quantum key distribution (QKD) is a cryptographic system that generates an information-theoretically secure key shared by two legitimate parties. QKD consists of two parts: quantum and classical. The latter is referred to as classical post-processing (CPP). Information reconciliation is a part of CPP in which parties are given correlated variables and attempt to eliminate the discrepancies between them while disclosing a minimum amount of information. The elegant reconciliation protocol known as \emph{Cascade} was developed specifically for QKD in 1992 and has become the de-facto standard for all QKD implementations. However, the protocol is highly interactive. Thus, other protocols based on linear block codes such as Hamming codes, low-density parity-check (LDPC) codes, and polar codes have been researched. In particular, reconciliation using LDPC codes has been mainly studied because of its outstanding performance. Nevertheless, with small block size, the bit error rate performance of polar codes under successive-cancellation list (SCL) decoding with a cyclic redundancy check (CRC) is comparable to state-of-the-art turbo and LDPC codes. In this study, we demonstrate the use of polar codes to improve the performance of information reconciliation in a QKD system with small block size. The best decoder for polar codes, a CRC-aided SCL decoder, requires CRC-precoded messages. However, messages that are sifted keys in QKD are obtained arbitrarily as a result of a characteristic of the QKD protocol and cannot be CRC-precoded. We propose a method that allows arbitrarily obtained sifted keys to be CRC precoded by introducing a virtual string. Thus the best decoder can be used for reconciliation using polar codes and improves the efficiency of the protocol.

arXiv:1805.05046•Quantum Information and Computation•Aug 1, 2018•4 citations

Flexible polar encoding for information reconciliation in QKD

Snehasis Addy, Sabyasachi Dutta, Somnath Panja +3 more

Quantum Key Distribution (QKD) enables two parties to establish a common secret key that is information-theoretically secure by transmitting random bits that are encoded as qubits and sent over a quantum channel, followed by classical information processing steps known as information reconciliation and key extraction. Transmission of information over a quantum channel introduces errors that are generally considered to be due to the adversary's tempering with the quantum channel and needs to be corrected using classical communication over an (authenticated) public channel. Commonly used error-correcting codes in the context of QKD include cascade codes, low-density parity check (LDPC) codes, and more recently polar codes. In this work, we explore the applicability of designing of a polar code encoder based on a channel reliability sequence. We show that the reliability sequence can be derived and used to design an encoder independent of the choice of decoder. We then implement our design and evaluate its performance against previous implementations of polar code encoders for QKD as well as other typical error-correcting codes. A key advantage of our approach is the modular design which decouples the encoder and decoder design and allows independent optimization of each. Our work leads to more versatile polar code-based error reconciliation in QKD systems that would result in deployment in a broader range of scenarios.

arXiv:2312.03100•Nov 30, 2023•0 citations

Efficient reconciliation protocol for discrete-variable quantum key distribution

David Elkouss, Anthony Leverrier, Romain Alléaume +1 more

Reconciliation is an essential part of any secret-key agreement protocol and hence of a quantum key distribution (QKD) protocol, where two legitimate parties are given correlated data and want to agree on a common string in the presence of an adversary, while revealing a minimum amount of information. In this paper, we show that for discrete-variable QKD protocols, this problem can be advantageously solved with low density parity check (LDPC) codes optimized for the binary symmetric channel (BSC). In particular, we demonstrate that our method leads to a significant improvement of the achievable secret key rate, with respect to earlier interactive reconciliation methods used in QKD.

arXiv:0901.2140•IEEE International Symposium on Information Theory (ISIT)•Jun 1, 2009•167 citations

Information Reconciliation for Quantum Key Distribution

David Elkouss, Jesús Martínez-Mateo, Vicente Martín Ayuso +1 more

Quantum key distribution (QKD) relies on quantum and classical procedures in order to achieve the growing of a secret random string -the key- known only to the two parties executing the protocol. Limited intrinsic efficiency of the protocol, imperfect devices and eavesdropping produce errors and information leakage from which the set of measured signals -the raw key- must be stripped in order to distill a final, information theoretically secure, key. The key distillation process is a classical one in which basis reconciliation, error correction and privacy amplification protocols are applied to the raw key. This cleaning process is known as information reconciliation and must be done in a fast and efficient way to avoid cramping the performance of the QKD system. Brassard and Salvail proposed a very simple and elegant protocol to reconcile keys in the secret-key agreement context, known as Cascade, that has become the de-facto standard for all QKD practical implementations. However, it is highly interactive, requiring many communications between the legitimate parties and its efficiency is not optimal, imposing an early limit to the maximum tolerable error rate. In this paper we describe a low-density parity-check reconciliation protocol that improves significantly on these problems. The protocol exhibits better efficiency and limits the number of uses of the communications channel. It is also able to adapt to different error rates while remaining efficient, thus reaching longer distances or higher secure key rate for a given QKD system.

•Oct 1, 2010•31 citations
Information reconciliation is a critical process of any Quantum Key Distribution (QKD) protocol, where two legitimate parties agree on a secret key. Two parties attempt to eliminate the discrepancies between their correlated keys in the presence of an adversary, while revealing a minimum amount of information. In this paper, we propose a reconciliation protocol using polar codes with a soft-output decoder. We demonstrate that our method is better than a conventional protocol using polar codes in the view of reconciliation efficiency.
Abstract Quantum key distribution (QKD) is a secure cryptographic technology that enables two authenticated parties to share secret keys. Information reconciliation is an essential step in continuous-variable quantum key distribution (CV-QKD) protocols, which affects both the complexity and performance of the system. This paper reviews adaptive reconciliation protocols, and also proposes a new efficient scheme using systematic polar codes. Simulation results show that the proposed scheme can significantly increase reconciliation efficiency and reduce the overall computational complexity by reducing the average number of retransmissions, without significant reduction in effective secret key length.
Quantum key distribution (QKD) enables two authenticated parties to share secret keys with the ability to detect any attempts to eavesdrop the keys theoretically. Currently, QKD systems can be categorized by its source of uncertainty in nature; single photon or coherent light. As coherent light is harnessed, the overall cost for composing systems drops in general. However, more elaborate post processing is required to extract and share errorless secret keys. Such process is called reconciliation, which is critical to performance. To extend the maximum distance to distill secret keys and prevent it from being bottleneck, we propose a reconciliation protocol that combines multidimensional reconciliation and polar codes. Especially, considering some practical issues, Gaussian approximation is chosen to construct polar codes. The simulation results show that the proposed protocol can support decent performance of coherent-light-based systems at long distance with reduced complexity.
Quantum key distribution (QKD) is a cryptographic system that generates an information-theoretically secure key shared by two legitimate parties. QKD consists of two parts: quantum and classical. The latter is referred to as classical post-processing (CPP). Information reconciliation is a part of CPP in which parties are given correlated variables and attempt to eliminate the discrepancies between them while disclosing a minimum amount of information. The elegant reconciliation protocol known as \emph{Cascade} was developed specifically for QKD in 1992 and has become the de-facto standard for all QKD implementations. However, the protocol is highly interactive. Thus, other protocols based on linear block codes such as Hamming codes, low-density parity-check (LDPC) codes, and polar codes have been researched. In particular, reconciliation using LDPC codes has been mainly studied because of its outstanding performance. Nevertheless, with small block size, the bit error rate performance of polar codes under successive-cancellation list (SCL) decoding with a cyclic redundancy check (CRC) is comparable to state-of-the-art turbo and LDPC codes. In this study, we demonstrate the use of polar codes to improve the performance of information reconciliation in a QKD system with small block size. The best decoder for polar codes, a CRC-aided SCL decoder, requires CRC-precoded messages. However, messages that are sifted keys in QKD are obtained arbitrarily as a result of a characteristic of the QKD protocol and cannot be CRC-precoded. We propose a method that allows arbitrarily obtained sifted keys to be CRC precoded by introducing a virtual string. Thus the best decoder can be used for reconciliation using polar codes and improves the efficiency of the protocol.
Quantum Key Distribution (QKD) enables two parties to establish a common secret key that is information-theoretically secure by transmitting random bits that are encoded as qubits and sent over a quantum channel, followed by classical information processing steps known as information reconciliation and key extraction. Transmission of information over a quantum channel introduces errors that are generally considered to be due to the adversary's tempering with the quantum channel and needs to be corrected using classical communication over an (authenticated) public channel. Commonly used error-correcting codes in the context of QKD include cascade codes, low-density parity check (LDPC) codes, and more recently polar codes. In this work, we explore the applicability of designing of a polar code encoder based on a channel reliability sequence. We show that the reliability sequence can be derived and used to design an encoder independent of the choice of decoder. We then implement our design and evaluate its performance against previous implementations of polar code encoders for QKD as well as other typical error-correcting codes. A key advantage of our approach is the modular design which decouples the encoder and decoder design and allows independent optimization of each. Our work leads to more versatile polar code-based error reconciliation in QKD systems that would result in deployment in a broader range of scenarios.
Reconciliation is an essential part of any secret-key agreement protocol and hence of a quantum key distribution (QKD) protocol, where two legitimate parties are given correlated data and want to agree on a common string in the presence of an adversary, while revealing a minimum amount of information. In this paper, we show that for discrete-variable QKD protocols, this problem can be advantageously solved with low density parity check (LDPC) codes optimized for the binary symmetric channel (BSC). In particular, we demonstrate that our method leads to a significant improvement of the achievable secret key rate, with respect to earlier interactive reconciliation methods used in QKD.
Quantum key distribution (QKD) relies on quantum and classical procedures in order to achieve the growing of a secret random string -the key- known only to the two parties executing the protocol. Limited intrinsic efficiency of the protocol, imperfect devices and eavesdropping produce errors and information leakage from which the set of measured signals -the raw key- must be stripped in order to distill a final, information theoretically secure, key. The key distillation process is a classical one in which basis reconciliation, error correction and privacy amplification protocols are applied to the raw key. This cleaning process is known as information reconciliation and must be done in a fast and efficient way to avoid cramping the performance of the QKD system. Brassard and Salvail proposed a very simple and elegant protocol to reconcile keys in the secret-key agreement context, known as Cascade, that has become the de-facto standard for all QKD practical implementations. However, it is highly interactive, requiring many communications between the legitimate parties and its efficiency is not optimal, imposing an early limit to the maximum tolerable error rate. In this paper we describe a low-density parity-check reconciliation protocol that improves significantly on these problems. The protocol exhibits better efficiency and limits the number of uses of the communications channel. It is also able to adapt to different error rates while remaining efficient, thus reaching longer distances or higher secure key rate for a given QKD system.