The Internet is going through a massive infrastructural revolution with the advent of low-flying satellite networks, 5/6G, WiFi7, and hollow-core fiber deployments. While these networks could unleash enhanced connectivity and new capabilities, it is critical to understand the performance characteristics to efficiently drive applications over them. Low-Earth orbit (LEO) satellite mega-constellations like SpaceX Starlink aim to offer broad coverage and low latencies at the expense of high orbital dynamics leading to continuous latency changes and frequent satellite hand-offs. This paper aims to quantify Starlink's latency and its variations and components using a real testbed spanning multiple latitudes from the North to the South of Europe. We identify tail latencies as a problem. We develop predictors for latency and throughput and show their utility in improving application performance by up to 25%. We also explore how transport protocols can be optimized for LEO networks and show that this can improve throughput by up to 115% (with only a 5% increase in latency). Also, our measurement testbed with a footprint across multiple locations offers unique trigger-based scheduling capabilities that are necessary to quantify the impact of LEO dynamics.
@article{arxiv.2310.11835,
title = {T3P: Demystifying Low-Earth Orbit Satellite Broadband},
author = {Shubham Tiwari and Saksham Bhushan and Aryan Taneja and Mohamed Kassem and Cheng Luo and Cong Zhou and Zhiyuan He and Aravindh Raman and Nishanth Sastry and Lili Qiu and Debopam Bhattacherjee},
journal= {arXiv preprint arXiv:2310.11835},
year = {2023}
}