Analysis of a rate-adaptive reconciliation protocol and the effect of the leakage on the secret key rate

Abstract

Quantum key distribution performs the trick of growing a secret key in two distant places connected by a quantum channel. The main reason is that the legitimate users can bound the information gathered by the eavesdropper. In practical systems, whether because of finite resources or external conditions, the quantum channel is subject to fluctuations. A rate adaptive information reconciliation protocol, that adapts to the changes in the communication channel, is then required to minimize the leakage of information in the classical postprocessing. We consider here the leakage of a rate-adaptive information reconciliation protocol. The length of the exchanged messages is larger than that of an optimal protocol; however, we prove that the min-entropy reduction is limited. The simulation results, both on the asymptotic and in the finite-length regime, show that this protocol allows to increase the amount of distillable secret key.

8 pages, 2 figures, accepted for publication in Physical Review A. This submission supersedes arXiv:1007.0904

References in corpus (5)

• Distillation of secret key and entanglement from quantum states
• Tight Finite-Key Analysis for Quantum Cryptography
• Quantum cryptography with finite resources: unconditional security bound for discrete-variable protocols with one-way post-processing
• Long Distance Continuous-Variable Quantum Key Distribution with a Gaussian Modulation
• Concise and Tight Security Analysis of the Bennett-Brassard 1984 Protocol with Finite Key Lengths

Cited by in corpus (2)

• Symmetric blind information reconciliation for quantum key distribution
• Experimental study and pratical realization of a reconciliation method for quantum key distribution system