A Topology Switching-Based Load Balancing Routing Scheme With Software-Hardware Separation for Satellite Ground Network

Low Earth Orbit (LEO) satellite network can provide the seamlessly global coverage and relatively low propagation delay, which has been envisioned as a key component of future 6G communication. However, the highly dynamic network topology and quite limited communication and computation resources of LEO satellites, alongside with uneven traffic distribution and demand of ground users impose a severe challenge for the routing algorithm design. To tackle this issue, we propose a ground block division and topology switching routing algorithm with software-hardware separation to handle the frequent uploading network topology and routing tables issue and reduce the computational and communication overheads. Furthermore, we estimate the long-term traffic demand in different ground blocks, and calculate the potential traffic demand for each block, and devise the Traffic Distribution Oriented Load Balancing Routing Algorithm (TDOLBRA) to avoid bottleneck links and reduce unnecessary overheads. Moreover, considering different Quality of Service (QoS) requirements of ground users’ traffic, we classify the traffic into high priority traffic and regular traffic, and adopt different routing strategies to further promote the network performance and resources utilization. Simulations results on STK and OPNET demonstrate that the proposed TDOLBRA scheme can have superior performance over three existing methods. To be specific, our proposed TDOLBRA scheme can achieve the best performance with respect to the fairness index, average traffic per link and packet drop rate Ploss. Especially, compared with three benchmark schemes, Ploss under our scheme is reduced by 3.4x, 7.6x, and 13.2x respectively when the total traffic is 18000 packets/min.