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Introduction

We investigated various PingER metrics derived from the ping measurements made from SLAC,  The most sensitive to this type of disruption appeared to be IPDV.

Using PingER data and comparing the various metrics it provides ( including: average Round Trip Time (RTT), Conditional Loss Probability (CLP). Inter Packet Delay Variability IPDV), Inter Quartile Range (IQR) of the round trip times, and derived throughput (see Tutorial on Internet Monitoring and Pinger at SLAC), we ; we ascertained that the most stable and yet sensitive metric in detecting changes caused by  Covid-19 interventions was the Inter Packet Delay Variation (IPDV). The data below analyzed are for 120 days starting around mid to late January 16th and ending around May 14th, mid to late May  2020. For each country, there is 1 point per day. Only Initially only weekday data is shown was used in order to reduce the variability of the data and to focus more on the effect of interventions such as closing the workplaces, schools, universities, people working from home, or being out of work. The weekday was determined based on the Universal Time  Coordinated (UTC).

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We are looking for a significant rise or fall in IPDV possibly correlated with an intervention or growth in cases. The links below point to charts of the IPDV (x-axis in msec.) versus the date. As mentioned above we only show data for the weekdays and there There is no data for 1/30/20 thru 2/2/20 (n.b. 2/1/30-2/2/30 are weekends).

Weekday data:

There are two Excel spread sheets for the weekday filtered data (two files since the master ran out of tabs): 

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  • Master most of the anaysis for ipdv 120days weekday data
  • Overflow remainder of analysis 

Alldays data

Since the weekdays data left gaps that either resulted in gaps in the curves or extended the curve across a weekend thus making the peaks look much wider, it made the data harder to understand by simple visualization, we decided to all daysNote that unless otherwise noted the charts in the above spreadsheet are for weekdays.

Results by region

Asia

E Asia

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Southern Europe

Western Europe

UK and Ireland

Summary

Since PingER was originally set up for monitoring connections between High Energy Physics (HEP) sites that were mainly in the US, Europe and Japan, . Thus these regions tend to have hosts that are mainly research or educational. As such they often have high-performance network links as opposed to public network links. See, for example the analysis for Spain and Italy, two countries that were badly impacted by Covid-19.

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