Hybrid terrestrial satellite quantum networks balance speed and quality
A Bi-Objective Routing Framework for Hybrid Terrestrial-Satellite Quantum Networks
Networking and Internet ArchitecturePerformance
Summary
Quantum networks connect distant points using particles of light that can be entangled for secure communication. These networks use both ground cables and satellites, but choosing the best path involves a trade-off between how fast the connection is (speed) and how accurate it is (quality). The authors created a new method that looks at both speed and quality at the same time, helping find the best routes between locations. Their approach finds all good compromises, giving users options depending on what matters more to their application.
What this means in practice
- •For quantum network operators: Choose optimal communication paths in hybrid quantum networks balancing speed and connection quality for specific application needs.
- •For satellite communication engineers: Design and manage integrated ground-satellite quantum links that provide flexible trade-offs between data transmission rates and reliability.
Authors
Yashpreet Khambay, Nitish K. Panigrahy
Abstract
Hybrid terrestrial-satellite quantum networks combine terrestrial fiber infrastructure with free-space links to enable long-distance entanglement distribution. Entanglement can be routed over different combinations of terrestrial and satellite links, resulting in paths with different entanglement generation rates (EGRs) and fidelities. Existing routing algorithms, however, typically reduce routing to a single-objective problem by optimizing either EGR or fidelity, or by optimizing one while constraining the other, and thus do not explicitly capture the trade-off between the two. In this paper, we present a bi-objective routing framework for hybrid quantum networks that jointly optimizes end-to-end EGR and fidelity. We formulate routing as a Pareto optimization problem and show that it possesses a special mathematical structure: the bottleneck nature of end-to-end EGR and the multiplicative nature of end-to-end fidelity allow the problem to be transformed into a MAXMIN-MINSUM bi-criterion path problem. This transformation enables the exact polynomial-time computation of a minimal complete Pareto set using Martins' bicriterion routing algorithm. Our results demonstrate that hybrid networks expose substantially richer Pareto frontiers than terrestrial-only networks and that the proposed framework outperforms representative single-objective routing policies by allowing applications to select paths based on their EGR and fidelity requirements.