Segment Routing based on Geographic Checkpoints

Low Earth Orbit (LEO) satellite constellations have highly dynamic network topologies, making conventional routing protocols inefficient. This paper presents Geographic Checkpoint Routing (GCR), a routing protocol that combines Geographic Routing and Segment Routing (SR) principles. Utilizing the structure of Walker Delta constellations, GCR eliminates the reliance on network topologies. It routes traffic through predefined geographic segments, offloads route computation to network edges, and allows traffic engineering through customizable policies without modifying satellite infrastructure. Simulations using the Starlink constellation show that GCR can match the performance of traditional source-based routing protocols without depending on network topologies.