With the increasing demand for secure communication in optical space networks, it is essential to develop physical-layer scalable security solutions. In this context, we present the asymptotic security analysis of a keyless quantum private communication protocol that transmits classical information over quantum states. Different from the previous literature, our protocol sends dummy (decoy) states optimally obtained from the true information to deceive the eavesdropper. We analyze optical on-off keying (OOK) and binary phase shift keying (BPSK) for several detection scenarios. Our protocol significantly improves the protocol without decoy states whenever Bob is at a technological disadvantage with respect to Eve. Our protocol guarantees positive secrecy capacity when the eavesdropper gathers up to 90-99.9% (depending on the detection scenario) of the photon energy that Bob detects, even when Eve is only limited by the laws of quantum mechanics. We apply our results to the design of an optical inter-satellite link (ISL) study case with pointing losses, and introduce a new design methodology whereby the link margin is guaranteed to be secure by our protocol. Hence, our design does not require knowing the eavesdropper’s location and/or channel state: the protocol aborts whenever the channel drops below the secured margin. Our protocol can be implemented with state-of-the-art space-proof technology. Finally, we also show the potential secrecy advantage when using (not yet available) squeezed quantum states technology.

中文翻译：

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具有空间信道诱饵态的量子无钥匙私人通信


随着光空间网络安全通信需求的不断增加，开发物理层可扩展的安全解决方案至关重要。在这种情况下，我们提出了通过量子态传输经典信息的无密钥量子私有通信协议的渐近安全分析。与以前的文献不同，我们的协议发送从真实信息中最佳获得的虚拟（诱饵）状态来欺骗窃听者。我们分析了几种检测场景的光学开关键控 (OOK) 和二进制相移键控 (BPSK)。当 Bob 相对于 Eve 处于技术劣势时，我们的协议显着改进了没有诱饵状态的协议。当窃听者收集到 Bob 检测到的高达 90-99.9%（取决于检测场景）的光子能量时，我们的协议保证了积极的保密能力，即使 Eve 仅受量子力学定律的限制。我们将我们的结果应用于具有指向损耗的光学卫星间链路（ISL）研究案例的设计，并引入了一种新的设计方法，通过我们的协议保证链路裕度的安全。因此，我们的设计不需要知道窃听者的位置和/或信道状态：只要信道低于安全裕度，协议就会中止。我们的协议可以通过最先进的太空技术来实施。最后，我们还展示了使用（尚不可用）压缩量子态技术时潜在的保密优势。