The creation of the future quantum Internet requires the development of new systems, architectures, and communications protocols. As a matter of fact, the optical fiber technology is affected by extremely high losses; thus, the deployment of a quantum satellite network (QSN) composed of quantum satellite repeaters (QSRs) in low Earth orbit would make it possible to overcome these attenuation problems. For these reasons, we consider the design of an ad hoc quantum satellite backbone based on the Software-Defined Networking (SDN) paradigm with a modular two-tier Control Plane (CP). The first tier of the CP is embedded into a Master Control Station (MCS) on the ground, which coordinates the entire constellation and performs the management of the CP integrated into the constellation itself. This second tier is responsible for entanglement generation and management on the selected path. In addition to defining the SDN architecture in all its components, we present a possible protocol to generate entanglement on the end-to-end (E2E) path. Furthermore, we evaluate the performance of the developed protocol in terms of the latency required to establish entanglement between two ground stations connected via the quantum satellite backbone.
Introduction to the Special Issue on Application-Specific Systems, Architectures and Processors