Inter-satellite links: optical vs RF, routing in space

Why Connect Satellites to Each Other

Inter-satellite links transform a constellation from a collection of independent relay nodes into a connected mesh network in space. Without ISLs, every packet must travel up to the satellite and immediately back down to a gateway, constraining traffic to regions with gateway coverage. With ISLs, traffic can hop across multiple satellites before descending to the nearest optimal gateway, dramatically expanding effective coverage and reducing reliance on ground infrastructure. This is especially valuable over oceans, polar regions, and areas where gateway deployment is impractical due to…