An Ephemeris and Handover Based Live Migration Scheme for Seamless Service Transfer in LEO Communications System

Facing the problem of rapid mobility of low Earth orbit (LEO) satellite, frequent handover process will occur while UE User Equipment (UE) is receiving service from satellite-based core network. The Quality of Service (QoS) for UE accessing the satellite-based core network cannot be ensured due to service interruptions and signaling storm caused by frequent handover. To solve this problem, we proposed a live migration scheme based on cooperation of ephemeris and UE handover request. In this scheme, we introduced a live migration method to transfer user and network function contexts in advance before initiating the handover process. Then, we built a simulation platform for the core network based on OAI (Open Air Interface) and validated the proposed network function live migration scheme through simulations. The simulation results indicate that our proposed live migration scheme can support on-demand, automatic deployment of core network functions in LEO satellites. The migration latency can be controlled within seconds, and the volume of migrated data is within the range supported by inter-satellite links.