Space-air-ground-sea integrated network (SAGSIN), which integrates satellite communication networks, aerial networks, terrestrial networks, and marine communication networks, has been widely envisioned as a promising network architecture for 6G. In consideration of its cooperation characteristics of multi-layer networks, open communication environment, and time-varying topologies, SAGSIN faces many unprecedented security challenges, and there have been a number of researches related to SAGSIN security performed over the past few years. Based on such observation, we provide in this paper a detailed survey of recent progress and ongoing research works on SAGSIN security in the aspects of security threats, attack methodologies, and defense countermeasures. To the best of our knowledge, we are the first to present the state-of-the-art of security for SAGSIN, since existing surveys focused either on a certain segment or on several segments of the integrated network, and little can be found on the full coverage network. In addition to reviewing existing works on SAGSIN security, we also present some discussions on cross-layer attacks and security countermeasure in SAGSIN, and identify new challenges ahead and future research directions.

中文翻译：

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6G天地海一体化网络安全综述


天空地海一体化网络（SAGSIN）融合了卫星通信网络、空中网络、陆地网络和海洋通信网络，被广泛认为是一种有前景的6G网络架构。考虑到其多层网络、开放通信环境和时变拓扑的协作特性，SAGSIN面临着许多前所未有的安全挑战，过去几年进行了大量与SAGSIN安全相关的研究。基于这样的观察，我们在本文中从安全威胁、攻击方法和防御对策等方面详细概述了 SAGSIN 安全的最新进展和正在进行的研究工作。据我们所知，我们是第一个展示 SAGSIN 最先进安全性的公司，因为现有的调查要么集中在集成网络的某个部分，要么集中在集成网络的多个部分，几乎找不到关于 SAGSIN 安全性的最新信息。网络全覆盖。除了回顾 SAGSIN 安全性的现有工作外，我们还对 SAGSIN 中的跨层攻击和安全对策进行了一些讨论，并确定了未来的新挑战和未来的研究方向。