×Grid: A Location-oriented Topology Design for LEO Satellites.

The high frequency at which handoff occurs between interconnected low-earth orbit (LEO) satellites pose a significant challenge in successfully implementing a satellite-based global Internet service. This is primarily due to the fact that LEO satellites only remain in range for approximately 3 minutes at a time, resulting in client state handoffs occurring 20x per hour. In this paper, we propose xGrid, a topology design for LEO satellites that leverages the predictability of satellite positions. Our design is location-oriented , allowing handoff to occur between satellites that share interconnected satellite links (ISLs). This approach contrasts with the current conventional topology designs, which require propagating client state information throughout the network and performing unnecessary computations to determine the appropriate return node for packets. Through simulations, we demonstrate that the xGrid reduces the number of ISL hops between major population centers and decreases the occurrence of dropped messages during handoff compared to conventional topology designs.