Costs and benefits of adaptation: evaluation in network congestion control

摘要在蜂窝通信中，移动的电话和基站需要调整连接它们的信道模型，以便消除反射信号。这种调整是对每个数据包进行的，开销是所有数据流量的大约七分之一对两端都是已知的，因此是无信息的。这就是适应的代价。好处是，尽管手机移动，通话仍然清晰。在网络通信中，环境变量是竞争业务，数据发送速率有两个目的：将数据传送到另一端，并探测网络以估计最大吞吐量。传输容量的很大一部分消耗在评估这些限制上。本研究的目的是探讨这种自适应系统中存在的权衡，以便可以开发出更高性能的方法。为了有效利用可变信道，必须损失多少容量？通过从一个熟悉的系统开始，我们希望认识到已经做出的设计调整和基于新理论的实际进步的机会。这项工作的智力价值在于将技术概念从系统理论扩展到网络随机演化的领域，例如描述流量行为。这带来了新的视角和数学工具，植根于工程实践。更广泛的影响，研究是它的连接到人？的经验。今天吗？的孩子们非常熟悉下载速度的可变性和计算机的行为，以适应这一点。因此，提供了一个入口，让学生参与硬理论，以解决日常问题，从而使他们尽早参与技术复杂性所提供的价值。

AbstractIn cellular communications, the mobile phone and the base station need to adapt their model of the channels connecting them in order to remove reflected signals. This adjustment is made with every data packet and the overhead is that about one seventh of all the data traffic is known to both ends and so is information-free. That is the price of adaptation. The benefit is that the call remains clear despite the motion of the cell phone. In network communications, the environmental variable is the competing traffic and the data send-rate serves two purposes; to convey data to the other end, and to probe the network to estimate the maximal throughput. A significant portion of the capacity for transmission is consumed in assessing these limits. The objective of this research is to explore the trade-offs present in such adaptive systems so that more highly performing approaches can be developed. How much capacity must be lost to achieve effective use of the variable channel? By commencing with a familiar system, we hope to recognize both the design adjustments already made and the opportunities for practical advances based on new theory.The intellectual merit of the work lies in extension of technical concepts from systems theory to the realm of random evolution of networks, such as describe the traffic behavior. This brings new perspectives and mathematical tools into that are rooted in engineering practice.The broader impact of the research is its connection to people?s experience. Today?s children are very familiar with the variability of download speeds and the behavior of computers to adjust to this. Thus an entrée is provided to involve students in hard theory to address everyday problems and therefore engage them early in the value provided by technical sophistication.