Weighted Cut-Criticality: A Topology-Physical Hybrid Metric for Identifying Critical Satellites in LEO Communication Constellations

Abstract

Identifying critical satellites in Low Earth Orbit (LEO) communication constellations is important for understanding network resilience. Classical centrality measures often do not account for two characteristics of LEO inter-satellite link topologies: the frequent presence of cut-vertices due to sparse connectivity, and the distance-dependent quality of individual links. This paper describes a metric called Weighted Cut-Criticality (WCC) that combines a node's structural cut-impact with its average incident link quality. The cut-impact counts the additional connected components created when a node is removed, while link quality is based on inverse-square distance weights of incident edges. Attack simulations are performed on a Walker-Delta constellation with 1584 satellites. Nodes are removed in descending order according to WCC, degree centrality, betweenness centrality, and pure cut-impact. The resulting degradation of the largest connected component and global network efficiency is compared. In the simulations, WCC-based removal leads to faster declines in both measures than the other metrics.