Quantum networks with satellites: hardware, protocol and architectures.

András Mihály, László Bacsárdi

Yaliang Shi, Zi Wang, Bangguo Yuan +2 more

The deployment of Low Earth Orbit (LEO) satellite constellations is an important step toward global-scale quantum networking. However, evaluating satellite quantum network protocols under spatiotemporal orbital dynamics and quantum physical constraints remains computationally expensive and challenging. In this paper, we propose QUASAR, a lightweight simulator for evaluating entanglement distribution in satellite-based quantum networks. QUASAR provides a decoupled architecture that integrates dynamic orbital topologies, time-varying optical transmittance, and quantum memory decoherence into network- layer attributes. To demonstrate its capabilities, we abstract and implement two representative hardware architectures: Simultaneous Downlink and On-Orbit Stitching. We further introduce an Entanglement Distribution Rate (EDR)-Aware Spatiotemporal Routing (EASR) heuristic as a reference workload. Our case study examines how QUASAR supports different satellite architectures, routing workloads, realistic orbital traces, concurrent requests, and scalable event-driven execution. With over 85% lower network-layer update latency than continuous polling, QUASAR provides a practical and extensible framework for future satellite quantum network protocol evaluation.

Bhabana Sarma, Harshit Tiwari, Ignacio Llamas‐Garro +2 more

ABSTRACT The rapid growth of global data traffic and the increasing demand for secure and scalable communication are driving the need for networking paradigms beyond the classical internet. The quantum internet has emerged as a promising solution, leveraging the principles of quantum mechanics to enable intrinsically secure communication, and computation. In this paper, we present a comprehensive review of the fundamental building blocks and system architectures required for large‐scale quantum networks, with a particular focus on photonic hardware platforms. We introduce key concepts of quantum information relevant to networking, including qubits, entanglement, and decoherence, and examine enabling technologies across different qubit platforms, highlighting photonic qubits as the primary carriers for long‐distance communication. We review major deterministic and probabilistic entanglement generation techniques, and analyze entanglement distribution strategies based on fiber, satellite, and quantum repeater architectures. Beyond the physical layer, we provide a system‐level perspective on quantum networking through protocol stack design, as well as challenges in entanglement routing, forwarding, and scheduling. Finally, we discuss experimental testbeds for entanglement distribution in both fiber‐based and free‐space systems, and outline the corresponding challenges and future research directions, including satellite‐assisted architectures for achieving scalable and globally connected quantum networks.

Kera Carter

Stephane Vinet, Thomas D. Jennewein, Ramy Tannous

We present a satellite-compatible reconfigurable quantum network architecture. During the satellite-pass the network adopts a point-to-multipoint topology where all the users communicate with the satellite, whereas outside of a satellite pass, the signal is rerouted to form a fully-connected network between the ground users. Exploiting multiplexing techniques, we show simulation results that indicate that this scheme can be used to enhance the secure key rate and to connect a multitude of users on the ground with minimal hardware requirements.

James Grow, Jayati Dutta, Sumit Chakravarty +1 more