In recent years, the Internet of Things (IoT) has been extensively investigated as an enabling technology to support massive devices or sensors. With increasing demands of seamless connectivity of IoT, space information networks (SINs) are adopted to provide reliable communications for IoT devices at any time and anywhere. However, the conventional SIN suffers from different malicious attacks (e.g., jamming attack, eavesdropping attack) due to its highly exposed satellite-ground links with fixed spot beams. Those attacks may cause severe security problems to SINs. To overcome these drawbacks, in this article, a secure architecture is proposed as a promising strategy to improve the security of SINs, where relays are deployed together with hopped beams to relieve the jamming attack of the uplink and combat the eavesdropping attack of the downlink. In the proposed new structure, by utilizing spatial diversity, inter-satellite beam hopping is developed to build jamming-free uplink channels, while relay selection is carried out to form eavesdropping-free downlink channels. Meanwhile, relay deployment optimization is studied to maximize the system efficiency, and data aggregation is adopted to encrypt the data packets of IoT devices at relays. As a result, the security of SINs can be strongly improved in the existence of jamming and eavesdropping threats. Furthermore, future works for the secure SIN are also discussed.

中文翻译：

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中继辅助空间信息网络的安全体系结构


近年来，物联网（IoT）作为支持大规模设备或传感器的使能技术得到了广泛的研究。随着物联网无缝连接的需求不断增加，采用空间信息网络（SIN）为物联网设备提供随时随地的可靠通信。然而，传统的SIN由于其高度暴露的具有固定点波束的星地链路而遭受不同的恶意攻击（例如干扰攻击、窃听攻击）。这些攻击可能会给 SIN 带来严重的安全问题。为了克服这些缺点，本文提出了一种安全架构作为提高 SIN 安全性的一种有前途的策略，其中中继与跳频波束一起部署，以减轻上行链路的干扰攻击并对抗下行链路的窃听攻击。在所提出的新结构中，利用空间分集，开发星间波束跳变来构建无干扰的上行链路信道，同时进行中继选择以形成无窃听的下行链路信道。同时，研究中继部署优化以最大化系统效率，并采用数据聚合对物联网设备在中继的数据包进行加密。因此，在存在干扰和窃听威胁的情况下，可以极大地提高SIN的安全性。此外，还讨论了安全 SIN 的未来工作。