ASER: Scalable Distributed Routing Protocol for LEO Satellite Networks
Xiang Zhang, Yuan Yang, Mingwei Xu, Jing Luo
Abstract
Low earth orbit (LEO) satellite networks are promising at constructing the satellite Internet. Dynamics of a large-scale LEO network topology induces critical problems on routing efficiency and scalability. Existing approaches either suffer from such routing problems, or have limited resilience against unpredictable link/node failures. We propose Area-based SatellitE Routing (ASER), a fully distributed routing protocol for LEO networks with high efficiency and scalability. ASER uses a hierarchical routing mechanism, which groups satellites into areas, in such a way that the inter-area routing never changes due to handovers of inter-satellite links. Routing can be quickly reconstructed with little overhead when either regular or unpredictable topology changes occur. We develop ASER based on OSPF, and propose an efficient algorithm to construct the forwarding table, enabling standard packet forwarding. Simulations validate that ASER can reduce the convergence time by more than 50%, and reduce computation and control overhead by orders of magnitude.