Efficient topology control for time-varying spacecraft networks with unreliable links

Abstract

In spacecraft networks, the time-varying topology, intermittent connectivity, and unreliable links make management of the network challenging. Previous works mainly focus on information propagation or routing. However, with a large number of nodes in the future spacecraft networks, it is very crucial regarding how to make efficient network topology controls. In this article, we investigate the topology control problem in spacecraft networks where the time-varying topology can be predicted. We first develop a model that formalizes the time-varying spacecraft network topologies as a directed space–time graph. Compared with most existing static graph models, this model includes both temporal and spatial topology information. To capture the characteristics of practical network, links in our space–time graph model are weighted by cost, efficiency, and unreliability. The purpose of our topology control is to construct a sparse (low total cost) structure from the original topology such that (1) the topology is still connected over space–time graph; (2) the cost efficiency ratio of the topology is minimized; and (3) the unreliability parameter is lower than the required bound. We prove that such an optimization problem is NP-hard. Then, we provide five heuristic algorithms, which can significantly maintain low topology cost efficiency ratio while achieving high reliable connectivity. Finally, simulations have been conducted on random space networks and hybrid low earth orbit/geostationary earth orbit satellite-based sensor network. Simulation results demonstrate the efficiency of our model and topology control algorithms.

Contact ability based topology control for predictable delay-tolerant networks

“…There are few studies on topology control under PDTNs, as far as we know, Huang et al 11 – 14 , Chen et al 15 , 16 , Yan et al 17 , 18 and Zhang et al 19 studied the topology control of PDTNs. Huang et al modeled the time-evolving network as a weighted space–time graph, which include temporal and spatial information.…”

“…They proposed a topology control strategy by using a kth shortest paths algorithm. Zhang et al 19 investigated the topology control problem in spacecraft networks where the time-varying topology can be predicted, and they modeled the spacecraft networks as a directed space–time graph, which also includes both temporal and spatial topology information too. They proposed five heuristic algorithms, which can significantly maintain low topology cost efficiency ratio while achieving high reliable connectivity.…”

“…As far as we know, Huang et al 11 – 14 and Chen et al 15 , 16 studied topology control in PDTNs. Yan et al 17 , 18 and Zhang et al 19 are also studied topology control in PDTNs. Taking into account temporal characteristics, they modeled PDTNs as a directed space–time graph containing spatial and temporal information.…”

Identification of Critical Nodes for Enhanced Network Defense in MANET-IoT Networks

“…Although the DMCC algorithm improves the identification speed by reducing the detection load, and the adaptive method improves the precise of identification by calculate the centrality adaptively, these two methods still only identify the critical nodes of the current topology snapshot without considering the association between topology snapshots. In spite of a topology snapshot corresponding to the topology of MANET at a particular time point, it has a direct impact on the evolution of the topology at the next time point [28]. If only considering current topology snapshot, the identification results will not be precise enough because in the combination of some short lifetime links with longer lifetime links, the importance of these short lifetime links are exaggerated.…”