NeTS: Small: Understanding and Weathering Variability in Low Earth Orbit Satellite Networks
PI: Ahmed Saeed - Georgia Tech
Co-PI: Ketan Bhardwaj - Georgia Tech
PI: Ahmed Saeed - Georgia Tech
Co-PI: Ketan Bhardwaj - Georgia Tech
Our lab studies how the distinctive dynamics of Low Earth Orbit (LEO) satellite networks affect their performance, reliability, and integration with the broader Internet. A major part of this work is empirical: we measure operational LEO networks to understand how satellite mobility, changing visibility, and evolving routing decisions shape user experience. Our large-scale studies have characterized latency, path changes, and geographic performance variation across Starlink, showing that frequent route shifts can introduce instability even when they provide limited latency benefit. More recently, we developed methods that combine multiple public datasets to detect significant changes in satellite-network usage without relying on proprietary operator telemetry. This enables researchers and policymakers to identify when communities become more dependent on satellite connectivity, including during natural disasters, conflicts, and failures of terrestrial infrastructure.
A second major thrust develops the simulation and analytical tools needed to evaluate satellite systems at scales and under conditions that cannot be studied through measurement alone. Our CosmoSim platform models constellation geometry, user demand, spectrum allocation, terminal deployment, incumbent traffic, and operator policies, enabling detailed analysis of both network performance and infrastructure planning. We used these capabilities to conduct a quantitative study of LEO constellations as emergency connectivity during large-scale submarine-cable disruptions. The results showed that satellite networks can provide valuable resilience, but that their contribution depends strongly on terminal placement, traffic prioritization, spectrum availability, gateway constraints, and coordination with existing users. Improved operational policies can substantially increase the capacity available during emergencies, yet satellites generally cannot replace more than a limited share of lost terrestrial capacity. This work has provided concrete guidance for governments, network operators, and satellite providers considering LEO systems as part of national resilience planning.
The lab’s outreach and educational activities broaden the impact of its satellite-networking research across the technical community, public-policy audiences, and students. Its study of route and latency variability in low-Earth-orbit networks was invited for presentation at the IETF 116 Measurement and Analysis for Protocols Research Group (MAPRG), helping bring the work to the Internet standards community. The lab also translated its research on using satellite networks as national emergency backup infrastructure into an Internet Society Pulse article and a policy-oriented paper at TPRC 53, identifying the technical limits of satellite failover and concrete policy choices available to governments and network operators. These efforts have provided research training for seven undergraduate students, several of whom contributed to the emergency-failover study, while satellite-network architectures, routing dynamics, and performance challenges have also been incorporated into undergraduate networking instruction.
