arXivDaily arXiv每日学术速递 周一至周五更新
arXiv cs/0701071cs.GT
收藏

一个有界度网络形成对策

A bounded-degree network formation game

Nikolaos Laoutaris, Rajmohan Rajaraman, Ravi Sundaram, Shang-Hua Teng

摘要:

出于对等网络和覆盖网络中的应用,我们定义并研究了\emph{Bounded Degree Network Formation}(BDNF)游戏。在$(n,k)$ -BDNF博弈中,我们被赋予$n$节点、每个节点的出度上的绑定$k$以及每个有序对$(v,u)$的权重$w_{vu}$,该权重表示从节点$v$到节点$u$的流量速率。每个节点$v$使用多达$k$定向链路来连接到其他节点,其目标是使用权重$w_{vu}$来最小化其到所有其他目的地的平均距离。研究了$(n,k)$ -BDNF博弈的纯纳什均衡的存在性。我们表明,如果权重是任意的,那么一个纯粹的纳什布线可能不存在。此外,确定对于给定的$(n,k)$ -BDNF实例是否存在纯Nash连接是NP难的。本文的一个主要重点是统一的$(n,k)$ -BDNF游戏,其中所有的权重为1。我们描述了如何构建一个纯粹的纳什均衡布线给定任何$n$和$k$,并建立在所有纯纳什布线的单个节点的成本不能相差超过近2的一个因素,而直径不能超过$O(\sqrt{n \log_k n})$。我们还分析了最佳响应步行的配置空间定义的统一的游戏,并表明,从任何初始配置,强连通性达到$Θ(n^2)$轮。然而,不能保证收敛到纯纳什均衡。我们目前的模拟结果表明,无环最佳响应的步行总是存在的,但可能不是多项式有界的。我们还研究了一个特殊的家庭的\emph{regular}布线,类的阿贝尔凯莱图,其中所有节点模仿相同的布线模式,并表明,如果$n$是足够大的,没有这样的定期布线可以是一个纯粹的纳什均衡。

英文摘要:

Motivated by applications in peer-to-peer and overlay networks we define and study the \emph{Bounded Degree Network Formation} (BDNF) game. In an $(n,k)$-BDNF game, we are given $n$ nodes, a bound $k$ on the out-degree of each node, and a weight $w_{vu}$ for each ordered pair $(v,u)$ representing the traffic rate from node $v$ to node $u$. Each node $v$ uses up to $k$ directed links to connect to other nodes with an objective to minimize its average distance, using weights $w_{vu}$, to all other destinations. We study the existence of pure Nash equilibria for $(n,k)$-BDNF games. We show that if the weights are arbitrary, then a pure Nash wiring may not exist. Furthermore, it is NP-hard to determine whether a pure Nash wiring exists for a given $(n,k)$-BDNF instance. A major focus of this paper is on uniform $(n,k)$-BDNF games, in which all weights are 1. We describe how to construct a pure Nash equilibrium wiring given any $n$ and $k$, and establish that in all pure Nash wirings the cost of individual nodes cannot differ by more than a factor of nearly 2, whereas the diameter cannot exceed $O(\sqrt{n \log_k n})$. We also analyze best-response walks on the configuration space defined by the uniform game, and show that starting from any initial configuration, strong connectivity is reached within $Θ(n^2)$ rounds. Convergence to a pure Nash equilibrium, however, is not guaranteed. We present simulation results that suggest that loop-free best-response walks always exist, but may not be polynomially bounded. We also study a special family of \emph{regular} wirings, the class of Abelian Cayley graphs, in which all nodes imitate the same wiring pattern, and show that if $n$ is sufficiently large no such regular wiring can be a pure Nash equilibrium.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑