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Exponential bandwidth scaling has been a fundamental driver of the growth and popularity of the Internet. However, increases in bandwidth have been accompanied by increases in power consumption, and despite sustained system design efforts to address power demand, significant technological challenges remain that threaten to slow future bandwidth growth. In(More)
The ability to generate repeatable, realistic network traffic is critical in both simulation and testbed environments. Traffic generation capabilities to date have been limited to either simple sequenced packet streams typically aimed at throughput testing, or to application-specific tools focused on, for example, recreating representative HTTP requests. In(More)
TCP <i>throughput prediction</i> is an important capability in wide area overlay and multi-homed networks where multiple paths may exist between data sources and receivers. In this paper we describe a new, lightweight method for TCP throughput prediction that can generate accurate forecasts for a broad range of file sizes and path conditions. Our method is(More)
Detecting the occurrence and location of performance anomalies (e.g., high jitter or loss events) is critical to ensuring the effective operation of network infrastructures. In this paper we present a framework for detecting and localizing performance anomalies based on using an active probe-enabled measurement infrastructure deployed on the periphery of a(More)
Measurement and estimation of packet loss characteristics are challenging due to the relatively rare occurrence and typically short duration of packet loss episodes. While active probe tools are commonly used to measure packet loss on end-to-end paths, there has been little analysis of the accuracy of these tools or their impact on the network. The(More)
Cellular and 802.11 WiFi are compelling options for mobile Internet connectivity. The goal of our work is to understand the performance afforded by each of these technologies in diverse environments and use conditions. In this paper, we compare and contrast cellular and WiFi performance using crowd-sourced data from Speedtest.net. Our study considers(More)
The ability to pinpoint the geographic location of IP hosts is compelling for applications such as on-line advertising and network attack diagnosis. While prior methods can accurately identify the location of hosts in some regions of the Internet, they produce erroneous results when the delay or topology measurement on which they are based is limited. The(More)
We describe Harpoon, a new application-independent tool for generating representative packet traffic at the <i>IP flow level</i>. Harpoon is a configurable tool for creating TCP and UDP packet flows that have the same byte, packet, temporal, and spatial characteristics as measured at routers in live environments. We validate Harpoon using traces collected(More)
Malicious traffic from self-propagating worms and denial-of-service attacks constantly threatens the everyday operation of Internet systems. Defending networks from these threats demands appropriate tools to conduct comprehensive vulnerability assessments of networked systems. This paper describes MACE, a unique environment for recreating a wide range of(More)
Examining the validity or accuracy of proposed available bandwidth estimation tools remains a challenging problem. A common approach consists of evaluating a newly developed tool using a combination of simple ns-type simulations and feasible experiments in situ (i.e., using parts of the actual Internet). In this paper, we argue that this strategy tends to(More)