Routing in LEO Satellite Networks over Packets Trapped by InterSatellite-Link Switch

Abstract

LEO (low-earth orbit) satellite networks has dynamic-featured topology in which periodic switch between connectivity and broken-off of ISL (intersatellite link) leads to topological change within switching gap, and forwarding packets would be trapped in satellite cache due to failure original route. Priority-based Rerouting in satellite networks and Shortest Path Set Algorithm with Path Prediction are proposed for sake of less trapped packets by ISL switching. Priority-based rerouting in satellite networks (PR) utilizes virtual topology model to shield dynamic-featured influence, chooses rerouting relay node with highest interplane ISL availability as selection criteria among the intra-orbit neighbors. Shortest Path Set Algorithm with Path Prediction (SPS with path prediction) selects the top three shortest paths as alternative and avoid node with impending interplane ISL failure and make best choice according to predictability of networking state. The two strategies are proved to reduce the trapping rate of forwarding packets.