Study on Scrambling Algorithms of Error Reconciliation in QKD

Quantum key distribution (referred to as QKD) is a technology that can produce and distribute secret keys unconditionally secure based on the principle of quantum mechanics. In a practical QKD system, the reconciliation efficiency is crucial to the final key rate of the system. A practical QKD system may produce the uneven error distribution of the sifted key due to the instabilities of optical and electronic devices and some other reasons, which will lead to the low reconciliation efficiency. Therefore, to scramble the sifted key is adopted in many QKD systems. In this paper, an Arnold-based Scrambling Algorithm and Fast Exchange Scrambling Algorithm are proposed mainly for the CASCADE class and WINNOW class error reconciliation algorithms. The experimental results demonstrate that the proposed algorithms provide the lower computational complexity and higher scrambling efficiency than the representative scrambling algorithm in QKD.