Quantum key distribution from satellites becomes particularly valuable when it can be used on a large network and on-demand to provide a symmetric encryption key to any two nodes. A constellation model is described which enables QKD-derived encryption keys to be established between any two ground stations with low latency. This is achieved through the use of low earth orbit, trusted-node QKD satellites which create a buffer of keys with the ground stations they pass over, and geostationary relay satellites to transfer secure combinations of the keys to the ground stations. Regional and global network models are considered and the use of inter-satellite QKD links for balancing keys is assessed.

中文翻译：

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可信节点 QKD 网络的卫星星座建模

当可以在大型网络上使用并按需向任意两个节点提供对称加密密钥时，来自卫星的量子密钥分发变得特别有价值。描述了一种星座模型，该模型能够以低延迟在任何两个地面站之间建立 QKD 派生的加密密钥。这是通过使用低地球轨道、受信任节点 QKD 卫星与它们经过的地面站创建密钥缓冲区以及地球同步中继卫星将密钥的安全组合传输到地面站来实现的。考虑了区域和全球网络模型，并评估了使用卫星间 QKD 链路来平衡密钥。