Enabling High-connectivity LEO Satellite Networks via Encountering Inter-Satellite Links

The use of a mega-constellation comprised of thousands of Low Earth Orbit (LEO) satellites for global internet service has garnered significant attention. In the network layer of this system, geographical routing has been found to outperform centralized strategies due to the lower complexity and overhead. However, geographical routing can still result in "dead-ends" due to network gaps. To address this issue, we propose the use of encountering inter-satellite links (eISLs) to improve network connectivity and routing reachability. We further present a system model and analysis of eISLs, as well as our Dynamic eISLs Configuration (DeC) algorithm for establishing eISLs between encountering satellites. Our experimental results demonstrate that our proposed DeC under eISLs enabling in satellite networks can significantly reduce propagation latency by 22% and path stretch by 15% in centralized routing algorithms. Moreover, in geographical routing, DeC can effectively improve the reachable ratio from 55% to 100% while maintaining a 28% increase in throughput, outperforming schemes without eISLs. Our proposed eISL-enabled satellite network architecture shows promising results in improving routing efficiency and connectivity in LEO satellite systems.