# Satellite-Assisted Disrupted Communications: IoT Case Study
## 6 Discussion  
Throughout our experiments, we investigated the impact of the number of satellites in a constellation on the resulting RTT and ping loss. While the topology of each experiment, particularly the location of the sender(s) and the receiver(s) on the map compared to the satellite constellation (planes, satellites, orbits, etc. ), plays a crucial role, in the majority of our experiments, increasing the number of satellites typically led to a reduction in the generated RTT and ping loss. Therefore, an inversely proportional relationship was detected. This observation aligns with the notion that larger constellations of satellites may more efficiently utilize available routes and paths between the sender and receiver. Moreover, in experiments where the _intersatelliteLink_ parameter was enabled, an additional reduction in the RTT and ping loss was noticed. This indicates that the utilization of inter-satellite links contributes to further optimizing communication performance in the simulated scenarios. Regarding the effect of inter-satellite links, our findings revealed consistently compressed range values for the RTT across all experiments involving active inter-satellite links. In fact, the minimum, maximum and mean RTT values exhibited reduced values when compared to scenarios without the _intersatelliteLink_ parameter (refer to Figure 7). This outcome is attributed to the interconnection of satellites within the same plane, resulting in shorter propagation delays, as opposed to higher propagation delays due to the more frequent connections of space and ground. As mentioned, inter-satellite links proved beneficial, serving as the sole alternative in scenarios where no ground station existed between a distant sender and receiver such as the case of Sensor[5] in Scenario 2. This was illustrated in Figure 6 where transmissions between Sensor[5] and the ground station in U.S. became impossible when the _intersatelliteLink_ parameter was disable, specifically in constellations comprising of 360 and 600 satellites. Surprisingly, we observed cases where the presence of inter-satellite links resulted in higher ping losses. Specifically, in Scenario 2, Sensor[8] (see Figure 6) exhibited lower ping losses when the _intersatelliteLink_ parameter was disabled. For instance, in the case of the 600 and 900 satellite constellations with inter-satellite links, there was a 13% increase in ping loss compared to the case where inter-satellite links were disabled. Figure 7: RTT per time for sensors 0, 1, 2, 8 in 360 satellite (first row), 600 satellite (second row) and 900 satellite (third row) constellations for Scenario 2. (a) RTT/time for Sensor 0; (b) RTT/time for Sensor 1; (c) RTT/time for Sensor 2; (d) RTT/time for Sensor 8. The primary limitations of our study can be attributed to the selection of the methodology and the nature of the real data acquired. At first, since ground-to-ground communications were excluded from this study, some possibly optimal results due to the more reliable ground communication i.e., better RTT or packet loss were not examined in the involved scenarios. In addition, although the \"hard-coded\" satellite design parameters--i.e., number of planes, satellites per plane etc.--allowed us to examine the impact of those design parameters on RTT and packet loss, real TLE sets of data were not used. Finally, since we integrated real data in OMNeT++, some experimentation results were limited by the frequency (i.e., timestamps) of the measured values. For instance, in certain sensors of scenario 2, a higher volume of data might led to more accurate or even surprising results with regards to the RTT and ping loss. One instance might have included notably higher RTTs due to the occupancy of some channels or a higher packet loss for the same reason.