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An End-to-End Test of the Sensitivity of IceCube to the Neutrino Burst from a Core-Collapse Supernova
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A paper by Zhang et al. in 2001, “On the Constancy of Internet Path Properties” [1] examined the constancy of end- to-end packet loss, latency, and throughput using a modest set of hosts deployed in the Internet. In the time since that work, the Internet has changed dramatically, including the flattening of the autonomous system hierarchy and increased deployment of IPv6, among other developments. In this paper, we investigate the constancy of end-to-end Internet latency, revisiting findings of the earlier study. We use latency measurements from RIPE Atlas, choosing a set of 124 anchors with broad geographic distribution and drawn from 112 distinct autonomous systems. The earlier work of Zhang et al. relies on changepoint detection methods to identify mathematically constant time periods. We reimplement the two methods described in that earlier work and use them on the RIPE Atlas latency measurements. We also use a recently- published method (HMM-HDP) that has direct support in a RIPE Atlas API. Comparing the three changepoint detection methods, we find that the two methods used in the earlier work may miss many changepoints caused by common level-shift events. Overall, we find that the recently proposed HMM-HDP method performs substantially better. Moreover, we find that delay spikes—as defined by the earlier work—are an order of magnitude less prevalent than 20 years ago. We also find that maximum change- free regions (CFRs) along paths that we observe in today’s Internet are substantially longer than what was observed in 2001, regardless of the changepoint detection method used. In particular, the 50th percentile maximum CFR was on the order of 30 minutes in the earlier study, but our analysis reveals it to be on the order of 3 days or longer. Moreover, we find that CFR durations appear to have steadily increased over the past 5 years.more » « less
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.22323/1.395.1085
