Publications Conference paper · Mega-constellations · 2025

Distributed On-Demand Routing for VLEO Constellations with 3-Terminal Inter-Satellite Links

Nicolò Benso, Alessandro Compagnoni, Gregory F. Stock, Juan A. Fraire, Gabriel Maiolini Capez, Camilla Ottaviani, Daniel Gaetano Riviello, Giacomo Verardo, Mirca Gargiulo, Leonardo Ospizio, Carla-Fabiana Chiasserini, and Roberto Garello

International Conference on Software, Telecommunications and Computer Networks (SoftCOM), pp. 1–7, 2025

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Abstract

This paper investigates routing strategies for Very Low Earth Orbit (VLEO) satellite constellations constrained by a three-terminal (3T) inter-satellite architecture, which is gaining interest as currently adopted by major operators (e.g., Starlink). In the 3T configuration, two terminals enable alongtrack communication, while a third hemispherical terminal can dynamically connect to either the left or right cross-plane neighbor, but not both simultaneously. This contrasts with the traditional four-terminal (4T) architecture, where four directional terminals enable full inter-plane links. The 3T constraint reduces crossplane connectivity, impacting path diversity, reachability, and latency. To address these challenges, we develop InterleavedScenario MinHopCount (IS-MHC) and DisCo3T, modified versions of the state-of-the-art routing algorithms Minimum Hop Count (MinHopCount) and Distributed On-Demand Routing for MegaConstellations (DisCoRoute) for the 3T case. Our new model accurately captures the limitations of 3T connectivity and reduces hop count in this scenario. We conduct a comprehensive evaluation of DisCo3T in terms of latency, hop count, and computational complexity, including a comparative analysis with the original 4T implementation. Results show that the topological constraints of the 3T configuration cause an average hop count increase of mathbf2 1. 7 % compared to the 4T baseline; however, DisCo3T retains the processing efficiency of the original 4 T algorithm.

Cite

DOI 10.23919/softcom66362.2025.11197383

BibTeX

@inproceedings{DBLP:conf/softcom/BensoCSFCORVGOCG25,
  author    = {Nicol{\`{o}} Benso and Alessandro Compagnoni and Gregory F. Stock and Juan A. Fraire and Gabriel Maiolini Capez and Camilla Ottaviani and Daniel Gaetano Riviello and Giacomo Verardo and Mirca Gargiulo and Leonardo Ospizio and Carla{-}Fabiana Chiasserini and Roberto Garello},
  title     = {Distributed On-Demand Routing for {VLEO} Constellations with 3-Terminal Inter-Satellite Links},
  booktitle = {International Conference on Software, Telecommunications and Computer Networks (SoftCOM)},
  pages     = {1--7},
  publisher = {{IEEE}},
  year      = {2025},
  doi       = {10.23919/softcom66362.2025.11197383}
}

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