Trace-driven Path Emulation of Satellite Networks using Hypatia

TL;DR

This paper presents a trace-driven path emulation system for satellite networks that enhances the evaluation of real applications by replaying recorded network characteristics in real-time environments, bridging simulation and real-world testing.

Contribution

It extends the Hypatia framework to enable trace-driven emulation of satellite networks, improving accuracy and adaptability over traditional simulation methods.

Findings

High correlation (up to 0.96) between emulation and simulation results

Effective reproduction of satellite network behavior in real-time emulation

Demonstrated adaptability to various satellite constellation scenarios

Abstract

The increasing prevalence LEO satellite mega-constellations for global Internet coverage requires new approaches to evaluate the behavior of existing Internet protocols and applications. Traditional discrete event simulators like Hypatia allow for modeling these environments but fall short in evaluating real applications. This paper builds upon our previous work, in which we proposed a system design for trace-driven emulation of such satellite networks, bridging the gab between simulations and real-time testbeds. By extending the Hypatia framework, we record network path characteristics, e.g., delay and bandwidth, between two endpoints in the network during non-real-time simulations. Path characteristics are exported to Trace Files, which are replayed in real-time emulation environments on real systems, enabling evaluations with real software and human interaction. An advantage of our approach is its easy adaptability to existing simulation models. Our extensive evaluation involves multiple scenarios with different satellite constellations, illustrating the approach's accuracy in reproducing the behavior of satellite networks. Between full simulation, which serves as a baseline for our evaluation, and emulation runs, we observe high correlation metrics of up to 0.96, validating the approach's effectiveness. Challenges such as the lack of emulation-to-simulation feedback and synchronization issues are discussed.