Sampling Rate Optimization for LDPC-Based Information Reconciliation Protocol in QKD

P. 1–7.

Morozov V., Oleg Evsutin, Nikita Yarygin

Quantum Key Distribution (QKD) is a promising field in modern cryptography where the security of key information is guaranteed by the laws of quantum mechanics. One of the key stages in QKD protocols is error estimation and reconciliation in the secret key. This procedure requires the transmission of a certain number of secret key bits over a public channel. Such transmission leads to disclosing these bits to a potential eavesdropper. The fraction of disclosed bits—the sampling rate-largely depends on the chosen approach for preliminary error estimation in the channel. This work is devoted to the optimization of the sampling rate for an LDPC code from the 5G standard. The results of our experiments show that for a QBER below 0.2 and key lengths of 264, 528, 792, and 1056 bits, it is necessary to disclose no more than 18%,11%,10%, and 7% of the key bits for error estimation, respectively. Furthermore, the proposed algorithm allows for similar optimization for any information reconciliation protocols and actual quantum bit error rates.

Keywords: информационная безопасность, error correction, случайная выборка, исправление ошибок, Quantum key distribution, random sampling, LDPC codes, Information security, квантовое распределение ключей, Error estimation, LDPC-КОДЫ, Оценка ошибок

Publication based on the results of: Development of Scientific and Technological Principles for Next-Generation Communication Networks Based on Quantum and Post-Quantum Cryptography Methods (2025)

In book

2025 XIХ International Symposium on Problems of Redundancy in Information and Control Systems (Redundancy), 5-7 Nov. 2025

IEEE, 2025.