arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1206.0150cs.DScs.DC
收藏

使最大独立集蜂鸣

Beeping a Maximal Independent Set

Yehuda Afek, Noga Alon, Ziv Bar-Joseph, Alejandro Cornejo, Bernhard Haeupler, Fabian Kuhn

摘要:

我们考虑的问题,计算一个最大的独立集(MIS)在一个非常苛刻的广播模型,只依赖于载波侦听。该模型由一个匿名的广播网络,其中的节点没有关于网络的拓扑结构,甚至其大小的上限的知识。此外,假设对手选择每个节点在哪个时隙醒来。在每个时隙,节点可以发出蜂鸣声,即发出信号,或者保持沉默。在特定时隙,发出蜂鸣声的节点不接收反馈,而静默节点只能区分没有其邻居发出蜂鸣声或至少有一个其邻居发出蜂鸣声。我们首先证明了一个下界,表明在这个模型中,它是不可能的局部收敛到MIS的子多项式时间。然后,我们研究了四种不同的松弛的模型,使我们能够绕过下限,并找到一个MIS在多对数时间。首先,我们证明了如果网络规模的多项式上界是已知的,那么在O(log^3 n)时间内找到MIS是可能的。其次,如果我们假设睡眠节点被邻近的哔哔声唤醒,那么我们也可以在O(log^3 n)时间内找到MIS。第三,如果除了这个唤醒假设之外,我们还允许发送端冲突检测,也就是说,发出哔哔声的节点可以区分是否至少有一个相邻节点同时发出哔哔声,那么我们可以在O(log^2 n)时间内找到MIS。最后,如果我们赋予节点同步时钟,也有可能在O(log^2 n)时间内找到MIS。

英文摘要:

We consider the problem of computing a maximal independent set (MIS) in an extremely harsh broadcast model that relies only on carrier sensing. The model consists of an anonymous broadcast network in which nodes have no knowledge about the topology of the network or even an upper bound on its size. Furthermore, it is assumed that an adversary chooses at which time slot each node wakes up. At each time slot a node can either beep, that is, emit a signal, or be silent. At a particular time slot, beeping nodes receive no feedback, while silent nodes can only differentiate between none of its neighbors beeping, or at least one of its neighbors beeping. We start by proving a lower bound that shows that in this model, it is not possible to locally converge to an MIS in sub-polynomial time. We then study four different relaxations of the model which allow us to circumvent the lower bound and find an MIS in polylogarithmic time. First, we show that if a polynomial upper bound on the network size is known, it is possible to find an MIS in O(log^3 n) time. Second, if we assume sleeping nodes are awoken by neighboring beeps, then we can also find an MIS in O(log^3 n) time. Third, if in addition to this wakeup assumption we allow sender-side collision detection, that is, beeping nodes can distinguish whether at least one neighboring node is beeping concurrently or not, we can find an MIS in O(log^2 n) time. Finally, if instead we endow nodes with synchronous clocks, it is also possible to find an MIS in O(log^2 n) time.

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。

↑