We consider a network of users connected by pairwise quantum key distribution (QKD) links. Using these pairwise secret keys and public classical communication, the users want to generate a common (conference) secret key at the maximal rate. We propose an algorithm based on spanning-tree packing (a known problem in graph theory) and prove its optimality. This algorithm enables optimal conference key generation in modern quantum networks of arbitrary topology. Additionally, we discuss how it can guide the optimal placement of new bipartite links in the network design.

翻译：考虑一个由用户通过成对量子密钥分发（QKD）链路连接的网络。用户希望利用这些成对密钥和公开经典通信，以最大速率生成共享的（会议）秘密密钥。我们提出一种基于泛树打包（图论中的一个已知问题）的算法，并证明其最优性。该算法能够在任意拓扑结构的现代量子网络中实现最优的会议密钥生成。此外，我们讨论了该算法如何指导网络设计中双向链路的最优部署。