Field test of the wavelength-saving quantum key distribution network

TL;DR

This paper presents a field-tested, wavelength-efficient quantum key distribution network using passive optical components, supporting multiple nodes with simultaneous secure key sharing over commercial telecom fiber.

Contribution

Introduces a novel wavelength-saving QKD network topology and demonstrates its practical implementation and performance in a real-world environment.

Findings

Supports 5 nodes with 2 wavelengths each

All links operate at 20 MHz frequency

Characterized insertion loss and crosstalk effects

Abstract

We propose a wavelength-saving topology of quantum key distribution(QKD) network based on passive optical elements, and report the field test of this network on the commercial telecom optical fiber. In this network, 5 nodes are supported with 2 wavelengths, and every two nodes can share secure keys directly at the same time. All QKD links in the network operate at the frequency of 20 MHz. We also characterized the insertion loss and crosstalk effects on the point-to-point QKD system after introducing this QKD network.