Network Creation Games(NCGs) model the creation of decentralized communication networks like the Internet. In such games strategic agents corresponding to network nodes selfishly decide with whom to connect to optimize some objective function. Past research intensively analyzed models where the agents strive for a central position in the network. This models agents optimizing the network for low-latency applications like VoIP. However, with today's abundance of streaming services it is important to ensure that the created network can satisfy the increased bandwidth demand. To the best of our knowledge, this natural problem of the decentralized strategic creation of networks with sufficient bandwidth has not yet been studied. We introduce Flow-Based NCGs where the selfish agents focus on bandwidth instead of latency. In essence, budget-constrained agents create network links to maximize their minimum or average network flow value to all other network nodes. Equivalently, this can also be understood as agents who create links to increase their connectivity and thus also the robustness of the network. For this novel type of NCG we prove that pure Nash equilibria exist, we give a simple algorithm for computing optimal networks, we show that the Price of Stability is 1 and we prove an (almost) tight bound of 2 on the Price of Anarchy. Last but not least, we show that our models do not admit a potential function.

中文翻译：

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基于流的网络创建游戏

网络创建游戏 (NCG) 模拟了互联网等分散式通信网络的创建。在此类博弈中，与网络节点对应的战略代理自私地决定与谁连接以优化某些目标函数。过去的研究深入分析了代理在网络中争取中心位置的模型。这为代理为低延迟应用程序（如 VoIP）优化网络建模。然而，随着当今流媒体服务的丰富，确保创建的网络能够满足增加的带宽需求非常重要。据我们所知，具有足够带宽的网络的分散战略创建这一自然问题尚未得到研究。我们引入了基于流的 NCG，其中自私的代理专注于带宽而不是延迟。在本质上，预算受限的代理创建网络链接以最大化它们到所有其他网络节点的最小或平均网络流量值。同样，这也可以理解为代理创建链接以增加其连接性，从而增加网络的健壮性。对于这种新型的 NCG，我们证明了纯纳什均衡存在，我们给出了一个计算最优网络的简单算法，我们证明了稳定价格为 1，我们证明了无政府状态价格的（几乎）紧边界为 2。最后但并非最不重要的一点是，我们表明我们的模型不承认潜在函数。对于这种新型的 NCG，我们证明了纯纳什均衡存在，我们给出了一个计算最优网络的简单算法，我们证明了稳定价格为 1，我们证明了无政府状态价格的（几乎）紧边界为 2。最后但并非最不重要的一点是，我们表明我们的模型不承认潜在函数。对于这种新型的 NCG，我们证明了纯纳什均衡存在，我们给出了一个计算最优网络的简单算法，我们证明了稳定价格为 1，我们证明了无政府状态价格的（几乎）紧边界为 2。最后但并非最不重要的一点是，我们表明我们的模型不承认潜在函数。