tailieunhanh - UNDERSTANDING INTERNET ROUTING ANOMALIES AND BUILDING ROBUST TRANSPORT LAYER PROTOCOLS

As the Internet grows and routing complexity increases, network-level instabilities are becoming more and more common. End-to-end communications are especially susceptible to service disruptions, while diagnosing and mitigating these disruptions are extremely challenging. In this dissertation, we design and build systems for diagnosing routing anomalies and improving robustness of end-to-end communications. The rst piece of this work describes PlanetSeer, a novel distributed system for diagnosing routing anomalies. PlanetSeer passively monitors traf c in wide-area services, such as Content Distribution Networks (CDNs) or Peer-to-Peer (P2P) systems, to detect anomalous behavior. It then coordinates active probes from multiple vantage points to con rm the anomaly, characterize it, and determine its scope. There are. | UNDERSTANDING INTERNET Routing A NOMALIES AND B UILDING Robust TRANSPORT LAYER PROTOCOLS Ming Zhang A Dissertation Presented to the Faculty OF Princeton University IN Candidacy for the Degree OF Doctor of Philosophy Recommended for Acceptance By the Department of Computer Science September 2005 Copyright by Ming Zhang 2005. All rights reserved. Abstract As the Internet grows and routing complexity increases network-level instabilities are becoming more and more common. End-to-end communications are especially susceptible to service disruptions while diagnosing and mitigating these disruptions are extremely challenging. In this dissertation we design and build systems for diagnosing routing anomalies and improving robustness of end-to-end communications. The first piece of this work describes PlanetSeer a novel distributed system for diagnosing routing anomalies. PlanetSeer passively monitors traffic in wide-area services such as Content Distribution Networks CDNs or Peer-to-Peer P2P systems to detect anomalous behavior. It then coordinates active probes from multiple vantage points to confirm the anomaly characterize it and determine its scope. There are several advantages of this approach first we obtain more complete and finer-grained views of routing anomalies since the wide-area nodes provide geographically-diverse vantage points. Second we incur limited additional measurement cost since most active probes are initiated when passive monitoring detects oddities. Third we detect anomalies at a much higher rate than other researchers have reported since the wide-area services provide large volumes of traffic to sample. Through extensive experimental study in the wide-area network we demonstrate that PlanetSeer is an effective system for both gaining a better understanding about routing anomalies and for providing optimization opportunities for the host service. To improve the robustness of end-to-end communications during performance anomalies we design mTCP a .