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  • IPv4: of the 728 hosts (out of almost 1300 in the PingER database) measured 50% have average(RTTs) within 2.15ms of one another.  The hosts are in 160 different countries with China having the most hosts with 195, followed by the United States with 52, Indonesia with 37, Malaysia with 27  and Pakistan with 13. In terms of regions the top region is East Asia with 206 hosts, 101 from Africa, 63 from Europe and 58 from North Amerca (Canada and the United States). There are 593 host that have 'www' in the name. The range of average ping RTTs is from 0.327ms to 377ms. The range of nping RTTs is from 2.3ms to 387ms.
    The Frequency histograms of average ping and average nping RTTS are shown below (Excel spreadsheet is here)

      

    It is seen that there is little difference in the two distributions. We thus compare  the Cumulative Distribution Frequencies (CDF) by plotting their differences, note this is a step towards using the Kolmogorov–Smirnov (K-S)  nonparametric test of the equality of continuous, one-dimensional probability distributions and yields a maximum difference (supremum) of 3.18% at 255 msec. K-S indicates that the probability of rejecting the null hypothesis (the null hypothesis says there is no relationship between the two measured phenomena) is high. 

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    To exemplify the differences in the RTTs measured by ping and nping we show the frequency distribution of the differences in the two Average RTTs. The histogram of the differences in the ping and nping averages RTTs is shown below.

    Another way of looking at the data is to consider the relative differences, i.e. (Avg(ping_RTT)-Avg(nping_RTT)/(0.5(Avg(ping_rtt)+Avg(nping_RTT)), this gives the distribution below that shows the IQR of the averge difference is ~ 1.2%. If one looks at the hosts that have relative differences of > 22% or less than -22% (about 2% of the hosts), we find most are from China or have low RTTs (< 4 msec).


  • IPv6: 50% of the 36 hosts measured have average(RTTs) within  0.26ms of oneanother). 


    Again the relative ping vs nping differences for IPv6 is shown below and shows an IQR of the relative average difference is 0.45%:

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