NeTS-NR: Counter-Intuitive Behavior in General Networks

提案编号：0435520PI：Steven LowInstitution：加利福尼亚理工学院标题：一般网络中的反直觉行为摘要众所周知，在分布式系统中可能会出现反直觉行为，其中代理优化他们自己的目标。本项目研究TCP网络中复杂的相互作用。重点是具有多个链路和异类流量的一般网络拓扑，以及严格的数学建模和分析。该项目开发数学理论来理解大规模网络的行为，在模拟和真实网络中验证这些理论见解，并将其用于网络和协议的实际设计和操作。初步结果表明，有趣和违反直觉的行为只有在流量通过多个共享链路以令人惊讶的方式交互的网络环境中才会出现。例如，研究人员已经证明，增加链路容量会降低TCP网络的总吞吐量，与传统观点相反，公平的带宽分配不一定是低效的。这个项目的结果将帮助我们更好地理解大规模网络的行为，特别是，有助于描述矛盾现象，并得出避免有害行为的指导方针。PI正在与普林斯顿EE的Mung Chiang教授合作，在入门研究生和高级本科生水平上开发一门新的课程--“通信网络的控制和优化”。该项目产生的成果将直接纳入新课程。我们还将利用并促进这一倡议的教育和外联活动。

Proposal Number: 0435520PI: Steven LowInstitution: California Institute of Technology Title: Counter-Intuitive Behavior in General Networks Abstract It is well-known that counter-intuitive behavior can arise in a distributed system where agents optimize their own objectives.This project studies the intricate interactions in TCP networks. The emphasis is on general network topologies with multiple links and heterogeneous flows and on rigorous mathematical modeling and analysis. The project develops mathematical theory to understand the behavior of large scale networks, verifies these theoretical insights in simulations and real networks, and exploits them in practical design and operation of networks and protocols.Preliminary results illustrate that interesting and counter-intuitive behavior arises only in a network setting where flows interact through multiple shared links in surprising ways. For example, the researchers have shown that increasing link capacity can reduce the aggregate throughput in a TCP network, and that, contrary to conventional wisdom, a fair bandwidth allocation is not necessarily inefficient. These results demonstrate that the formal approach taken in the project is indeed necessary and rewarding.The results of this project will help us better understand behavior of large-scale networks such as the Internet, and in particular, help characterize paradoxical phenomenon and derive guidelines to avoid harmful behavior in TCP networks.Together with Professor Mung Chiang of Princeton EE, the PI is developing a new course on ``Control and optimization of communication networks'', at the introductory graduate andadvanced undergraduate level. The results produced in the project will be directly incorporated into the new course. We will also leverage on, and contribute to, the education and outreach activities of this initiative.