Parallel trusted node approach for satellite quantum key distribution

TL;DR

This paper proposes a parallel trusted node approach for satellite-based quantum key distribution, enhancing security and reliability by distributing trust across multiple satellites in a global quantum network.

Contribution

It introduces a novel parallel trusted node protocol for satellite QKD, reducing single points of failure and trust assumptions in global quantum communication.

Findings

Distributes trust across multiple satellites

Reduces single points of failure

Enhances security in global quantum networks

Abstract

Quantum key distribution (QKD) via satellite links is the only currently viable solution to create quantum-backed secure communication at a global scale. To achieve intercontinental coverage with available technology one must adopt a "flying trusted node" paradigm, in which users fully trust the satellite platform. Here, inspired by the concept of distributed secret sharing and the imminent projected launch of several QKD-equipped satellites, we propose a parallel trusted node approach, in which key distribution is mediated by several satellites in parallel. This has the effect of distributing the trust, removing single points of failure and reducing the necessary assumptions. In addition, we discuss the versatility that an optical ground station should provide to execute such a protocol and, in general, to be fully integrated into a multi-party global quantum network.