Asymptotically Secure Network Code for Active Attacks and its Application to Network Quantum Key Distribution

TL;DR

This paper develops an asymptotic secure network coding framework resilient to active attacks, with applications to quantum key distribution networks enabling secure long-distance communication.

Contribution

It introduces new asymptotic rate results for secure network coding under active attacks and applies them to quantum key distribution networks.

Findings

Achieves secure communication in networks with malicious attackers.

Provides asymptotic rate bounds for secrecy and robustness.

Enables long-distance quantum communication using short-distance QKD.

Abstract

When there exists a malicious attacker in the network, we need to be careful of eavesdropping and contamination. This problem is crucial for network communication when the network is realized by a partially trusted relay of quantum key distribution. We discuss the asymptotic rate in a linear network with the secrecy and robustness conditions when the above type of attacker exists. Also, under the same setting, we discuss the asymptotic rate in a linear network when we impose the secrecy condition alone. Then, we apply these results to the network composed of a partially trusted relay of quantum key distribution, which enables us to realize secure long-distance communication via short-distance quantum key distribution.