Gonca Gürsun

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Computer systems are increasingly driven by workloads that reflect large-scale social behavior, such as rapid changes in the popularity of media items like videos. Capacity planners and system designers must plan for rapid, massive changes in workloads when such social behavior is a factor. In this paper we make two contributions intended to assist in the(More)
A traffic matrix encompassing the entire Internet would be very valuable. Unfortunately, from any given vantage point in the network, most traffic is invisible. In this paper we describe results that hold some promise for this problem. First, we show a new characterization result: traffic matrices (TMs) typically show very low effective rank. This result(More)
Mobility models have traditionally been tailored to specific application domains such as human, military, or ad hoc transportation scenarios. This tailored approach often renders a mobility model useless when the application domain changes, and leads to wrong conclusions about the performance of protocols and applications running atop of different domains.(More)
The ability of an ISP to infer traffic volumes that are not directly measurable can be useful for research, engineering, and business intelligence. Previous work has shown that <i>traffic matrix completion</i> is possible, but there is as yet no clear understanding of which ASes are likely to be able to perform TM completion, and which traffic flows can be(More)
Characterizing the set of routes used between domains is an important and difficult problem. The size and complexity of the millions of BGP paths in use at any time can hide important phenomena and hinder attempts to understand the path selection behavior of ASes. In this paper we introduce a new approach to analysis of the interdomain routing system(More)
The dynamics of interdomain routing have traditionally been studied through the analysis of BGP update traffic. However, such studies tend to focus on the volume of BGP updates rather than their effects, and tend to be local rather than global in scope. Studying the global state of the Internet routing system over time requires the development of new(More)
Consider this simple question: how can a network operator identify the set of routes that pass through its network? Answering this question is surprisingly hard: BGP only informs an operator about a limited set of routes. By observing traffic, an operator can only conclude that a particular route passes through its network -- but not that a route does not(More)
The goal of Content Delivery Networks (CDNs) is to serve content to end-users with high performance. In order to do that, a CDN measures the latency on the paths from its servers to users and then selects a best available server for each user. For large CDNs, monitoring paths from thousands of servers to millions of users is a challenging task due to its(More)
Latency is one of the most critical performance metrics for a wide range of applications. Therefore, it is important to understand the underlying mechanisms that give rise to the observed latency values and diagnose the ones that are unexpectedly high. In this paper, we study the Internet delay space via robust principal component analysis (RPCA). Using(More)
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