Network Coding-Based Multipath Transmission for LEO Satellite Networks With Domain Cluster

In the large-scale dynamic low-Earth orbit (LEO) satellite networks, the conventional TCP-based single-path transmission encounters challenges, such as prolonged propagation delay, frequent connection failures, and suboptimal resource utilization. In this article, we propose an integrated multipath network coding (IMPNC) transmission scheme. This scheme leverages multiple paths for end-to-end transmission to achieve bandwidth aggregation and redundant backup. The multipath transmission is facilitated by multipath quick UDP Internet connection (MPQUIC) protocol to adapt to the limited satellite bandwidth and caching resources. The proposed approach involves encoding packets at nodes along the paths, addressing the significant out-of-order problem arising from variable delays on different paths. Additionally, we present a software-defined networking (SDN)-based domain clustering architecture, which offers a more streamlined control approach, reducing overall complexity. Furthermore, we formulate the domain clustering problems as mixed-integer nonlinear programming and the coding-based routing problem as a Steiner tree problem. Evaluation results demonstrate that the proposed scheme effectively reduces the latency over 25.1%, enhances bandwidth utilization by 19.6%, and ensures reliable data transmission by reducing retransmission probability by 4.1%.