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—HTTP video streaming, such as Flash video, is widely deployed to deliver stored media. Owing to TCP's reliable service, the picture and sound quality would not be degraded by network impairments, such as high delay and packet loss. However, the network impairments can cause rebuffering events which would result in jerky playback and deform the video's(More)
Dynamic Adaptation Streaming over HTTP (DASH) enhances the Quality of Experience (QoE) for users by automatically switching quality levels according to network conditions. Various adaptation schemes have been proposed to select the most suitable quality level during video playback. Adaptation schemes are currently based on the measured TCP throughput(More)
Conducting network measurement in a web browser (e.g., speedtest and Netalyzr) enables end users to understand their network and application performance. However, very little is known about the (in)accuracy of the various methods used in these tools. In this paper, we evaluate the accuracy of ten HTTP-based and TCP socket-based methods for measuring the(More)
Measuring network path capacity is an important capability to many Internet applications. But despite over ten years of effort, the capacity measurement problem is far from being completely solved. This paper addresses the problem of measuring network paths of asymmetric capacity without requiring the remote node's control or overwhelming the bottleneck(More)
—Network faults, such as router failures, cable out-ages, and configuration errors, could seriously affect network performance. In this paper, we use network faults very loosely, including those that will yield unfavorable end-to-end network performance, such as packet reordering and suboptimal routes. Diagnosing network faults on end-to-end paths is a very(More)
Crowdtesting is increasingly popular among researchers to carry out subjective assessments of different services. Experimenters can easily assess to a huge pool of human subjects through crowdsourcing platforms. The workers are usually anonymous, and they participate in the experiments independently. Therefore, a fundamental problem threatening the(More)
A number of home-installed middleboxes, e.g., BISMark and SamKnows, and web-based tools, e.g., Netalyzr and Ookla's speedtest service, have been developed recently to enable residential broadband users to gauge their network service quality. One challenge to designing these systems is to provide stable network measurement. That is, the measurement results(More)
—As most of mobile apps rely on network connections for their operations, measuring and understanding the performance of mobile networks is becoming very important for end users and operators. Despite the availability of many measurement apps, their measurement accuracy has not received sufficient scrutiny. In this paper, we appraise the accuracy of(More)
A number of projects deploy Linux-based embedded systems to carry out large-scale active network measurement and network experiments. Due to resource constrains and the increase of network speed, obtaining sound measurement results from these low-end devices is very challenging. In this paper, we present a novel network primitive, OMware, to improve the(More)