MaCro: Mega-Constellations Routing Systems with Multi-Edge Cross-Domain Features

With satellite networks evolving toward gigantic, hybrid, and heterogeneous, non-terrestrial networks (NTN) have become one of the key research topics in 6th Generation (6G) networks. Routing, as the basic technology in NTN, has faced severe challenges. With the continuous increase of satellite constellation, for example, the huge control signaling overhead, frequent link disruption, and multi-mode traffic requirements are problems. In this article, a novel Mega-Constellations Routing (MaCRo) system with multi-edge and cross-domain features is proposed. Control and user plane are separated in order to support flexible network management of multi-layer satellite networks, based on software defined networks (SDN) and multi-access edge computing (MEC) technologies. Cross-domain resources, including communication, storage, computing, conception, and control, are utilized to realize unified scheduling for task-oriented routing. Four typically collaborative modes are discussed and the corresponding functional difference are summarized and compared. Finally, cases are studied and illustrated with key procedures, including intelligent area-segmentation routing and computational power routing. Numerical results show that the hybrid mode proposed in the MaCRo systems outperforms the other routing modes in average end-to-end latency and packet loss rate. The proposed routing system appears to be highly attractive as part of the future 6G NTN networks.