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6 Internet-Scale Network Coordinates
Using a latency matrix can only tell part of the story of an Internet coordinate system. It helps describe the network's characteristics, e.g., its intrinsic dimensionality, but misses out on problems that may occur only in a running system, such as churn, changes in latencies over time, and measurement anomalies. We used three distinct methods to understand the online performance of Azureus' coordinates: (a) on PlanetLab, we ran instrumented Azureus clients that recorded the entirety of their coordinate-related behavior (Section 6.2), (b) we crawled approximately ten thousand Azureus clients that internally tracked the performance of their coordinates using statistics we inserted into the Azureus code (Section 6.3), and (c) we ran a benchmark to determine the effectiveness of the coordinates on application-level decisions (Section 6.4).
Jonathan Ledlie 2007-02-23