  In this paper, we present our work in designing and implementing a LEO
satellite constellation simulation model1 within OMNeT++ and INET, which is
validated by comparing the results with existing work. Our model builds upon
the fundamentals of the Open Source Satellite Simulator (OS$^3$), which was
ported to INET 4.3. We describe how the model was integrated on top of the INET
and ported OS$^3$ Framework. We then experiment with the simulation model to
demonstrate its viability in simulating LEO satellite constellations. This
involved simulating both outdated and more recent satellite constellations,
using FCC filing information, to validate latency results.
