PH-BGP: A Proactive Hierarchical Border Gateway Protocol Routing Scheme and System in Ultra-Dense LEO Satellite Network

The ultra-dense low earth orbit (LEO) satellite networks are becoming indispensable infrastructures for future sixth-generation (6 G) architectures by providing low-latency and high-speed communication. A LEO satellite network can be viewed as an autonomous system (AS), which necessitates seamless integration with terrestrial ASes using Border Gateway Protocol (BGP). However, traditional BGP and existing optimization have not sufficiently considered the significant overhead of BGP and its adaptability to high dynamics. In this paper, we propose a Proactive Hierarchical Border Gateway Protocol (PH-BGP) routing scheme and system tailored for ultra-dense LEO networks. Specifically, we develop an inter-domain routing scheme leveraging hierarchical convergence and proactive updating to balance routing overhead and network stability, which accelerates route convergence. Based on previous work, we develop a modular routing system, which utilizes a prediction module, decision module, hierarchical convergence mechanism module, and proactive routing update mechanism module to collaborate. Our simulation results on real-world typical Walkerdelta type LEO constellations demonstrate that PH-BGP is effective and superior compared to other routing schemes.