International Conference Education and Creativity for a Knowledge-based Society – Informatics

INFORMATION RECONCILIATION IN QKD: A COMPARATIVE ANALYSIS OF CASCADE, LDPC AND POLAR CODES

Liliana Zisu, Ciprian Răcuciu

Published Jun 11, 2026• 0 citations

Abstract

Quantum Key Distribution (QKD) provides unconditional security, but requires a robust information reconciliation step to eliminate errors introduced by the quantum channel. The efficiency of this step directly determines the net secret key generation rate. The paper presents a detailed comparative analysis of three major reconciliation techniques: CASCADE, LDPC (Low-Density Parity-Check), and Polar Codes. The analysis focuses on seven essential metrics, including reconciliation efficiency (f), maximum error tolerance (QBERmax,), final secure key rate (R), frame error rate (FER), and computational complexity. Simulations are performed on a realistic QKD channel model (BB84 with depolarization), with QBER varying between 0.1% and 16%, covering experimental conditions. Keywords: QKD, Information Reconciliation, LDPC, CASCADE, Polar Codes, Secret Key Rate

DOI: 10.66793/titui19proceeding10

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