NTPsec

ntp2.wiktel.com

Report generated: Mon May 19 16:45:06 2025 UTC
Start Time: Mon May 12 16:45:00 2025 UTC
End Time: Mon May 19 16:45:00 2025 UTC
Report Period: 7.0 days

Top   Daily Stats   Weekly Stats  

Local Clock Time/Frequency Offsets

local offset plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local Clock Time Offset -392.906 -8.119 -4.801 0.340 3.250 4.830 282.978 8.051 12.949 2.701 -0.008 µs -7.288 2281
Local Clock Frequency Offset -13.274 -13.185 -13.142 -12.850 -12.522 -12.473 -6.927 0.620 0.712 0.224 -12.830 ppm -1.993e+05 1.165e+07

The time and frequency offsets between the ntpd calculated time and the local system clock. Showing frequency offset (red, in parts per million, scale on right) and the time offset (blue, in μs, scale on left). Quick changes in time offset will lead to larger frequency offsets.

These are fields 3 (time) and 4 (frequency) from the loopstats log file.



Local RMS Time Jitter

local jitter plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local RMS Time Jitter 0.396 1.015 1.338 2.711 4.759 5.948 272.264 3.421 4.933 1.775 2.845 µs 68.64 7951

The RMS Jitter of the local clock offset. In other words, how fast the local clock offset is changing.

Lower is better. An ideal system would be a horizontal line at 0μs.

RMS jitter is field 5 in the loopstats log file.



Local RMS Frequency Jitter

local stability plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local RMS Frequency Jitter 0.675 1.630 2.167 4.296 7.352 8.972 1,563.584 5.185 7.342 8.304 4.547 ppb 123.1 1.797e+04

The RMS Frequency Jitter (aka wander) of the local clock's frequency. In other words, how fast the local clock changes frequency.

Lower is better. An ideal clock would be a horizontal line at 0ppm.

RMS Frequency Jitter is field 6 in the loopstats log file.



Local Clock Time Offset Histogram

local offset histogram plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local Clock Offset -392.906 -8.119 -4.801 0.340 3.250 4.830 282.978 8.051 12.949 2.701 -0.008 µs -7.288 2281

The clock offsets of the local clock as a histogram.

The Local Clock Offset is field 3 from the loopstats log file.



Server Offsets

peer offsets plot

The offset of all refclocks and servers. This can be useful to see if offset changes are happening in a single clock or all clocks together.

Clock Offset is field 5 in the peerstats log file.



Server Offset 132.163.97.5

peer offset 132.163.97.5 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 132.163.97.5 -1.141 -1.121 -1.110 -1.072 2.231 2.264 5.375 3.342 3.385 0.914 -0.831 ms -8.901 23.54

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset 132.246.11.229

peer offset 132.246.11.229 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 132.246.11.229 -3.909 -1.104 -0.877 -0.759 -0.562 2.298 2.351 0.315 3.402 0.619 -0.675 ms -12.67 45.19

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset 134.84.84.84

peer offset 134.84.84.84 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 134.84.84.84 -74.395 -50.089 -35.462 -8.554 19.473 31.845 52.960 54.935 81.934 16.765 -7.972 µs -7.683 21.65

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset 204.9.54.119

peer offset 204.9.54.119 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 204.9.54.119 -0.913 -0.906 -0.902 -0.893 -0.880 2.565 2.575 0.022 3.470 0.624 -0.777 ms -12.88 36.95

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset 2600:2600::99 (ntp1.wiktel.com)

peer offset 2600:2600::99 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2600:2600::99 (ntp1.wiktel.com) -376.899 -365.777 -359.463 -343.288 -327.734 -320.550 -314.291 31.729 45.227 9.772 -343.200 µs -4.724e+04 1.71e+06

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset 2606:4700:f1::1 (time.cloudflare.com)

peer offset 2606:4700:f1::1 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2606:4700:f1::1 (time.cloudflare.com) -2.913 -2.219 -1.928 -0.326 -0.002 0.312 0.349 1.926 2.531 0.542 -0.422 ms -13.14 51.43

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset 2606:4700:f1::123 (time.cloudflare.com)

peer offset 2606:4700:f1::123 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2606:4700:f1::123 (time.cloudflare.com) -2.919 -2.555 -0.525 -0.397 -0.106 0.305 0.610 0.419 2.860 0.402 -0.412 ms -18.29 95.39

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset 2607:f128::50

peer offset 2607:f128::50 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2607:f128::50 698.625 722.144 740.867 781.588 818.361 837.301 856.804 77.494 115.157 23.738 780.725 µs 3.253e+04 1.04e+06

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset 2607:f388::123:2 (ntp2.doit.wisc.edu)

peer offset 2607:f388::123:2 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2607:f388::123:2 (ntp2.doit.wisc.edu) -216.559 -129.368 -86.723 -30.157 37.961 104.866 223.772 124.684 234.234 40.453 -27.998 µs -9.193 28.48

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset SHM(1)

peer offset SHM(1) plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset SHM(1) -0.000 -0.000 -0.000 0.000 0.000 0.000 15.000 0.000 0.000 0.436 0.013 s 30.5 1052

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Jitters

peer jitters plot

The RMS Jitter of all refclocks and servers. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 132.163.97.5

peer jitter 132.163.97.5 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 132.163.97.5 7.471 13.313 18.541 35.943 63.143 547.289 3,332.128 44.602 533.976 216.527 56.968 µs 9.678 128.3

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 132.246.11.229

peer jitter 132.246.11.229 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 132.246.11.229 0.020 0.046 0.083 0.234 1.210 2.643 3.421 1.127 2.597 0.444 0.368 ms 3.147 16.24

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 134.84.84.84

peer jitter 134.84.84.84 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 134.84.84.84 1.690 2.577 3.693 8.049 18.968 30.886 148.255 15.275 28.309 9.306 9.805 µs 8.995 110.4

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 204.9.54.119

peer jitter 204.9.54.119 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 204.9.54.119 0.003 0.004 0.006 0.010 0.017 1.299 3.454 0.011 1.295 0.271 0.038 ms 7.177 83.28

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 2600:2600::99 (ntp1.wiktel.com)

peer jitter 2600:2600::99 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2600:2600::99 (ntp1.wiktel.com) 3.376 6.407 9.229 19.778 35.339 438.680 453.108 26.110 432.273 45.825 25.289 µs 7.328 65.76

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 2606:4700:f1::1 (time.cloudflare.com)

peer jitter 2606:4700:f1::1 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2606:4700:f1::1 (time.cloudflare.com) 2.975 4.873 6.986 16.655 101.714 349.195 2,898.149 94.728 344.322 182.055 42.396 µs 9.709 138.1

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 2606:4700:f1::123 (time.cloudflare.com)

peer jitter 2606:4700:f1::123 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2606:4700:f1::123 (time.cloudflare.com) 2.555 5.184 6.649 15.394 86.770 533.631 2,895.625 80.121 528.447 204.334 43.444 µs 8.519 109.2

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 2607:f128::50

peer jitter 2607:f128::50 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2607:f128::50 6.544 12.090 16.230 33.228 70.024 300.481 1,113.768 53.794 288.391 73.902 43.236 µs 9.7 122

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 2607:f388::123:2 (ntp2.doit.wisc.edu)

peer jitter 2607:f388::123:2 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2607:f388::123:2 (ntp2.doit.wisc.edu) 4.241 9.487 12.504 24.879 70.595 93.631 416.790 58.091 84.144 21.608 30.099 µs 8.184 117.2

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter SHM(1)

peer jitter SHM(1) plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter SHM(1) 0.000 0.000 0.000 0.000 0.000 0.000 15.000 0.000 0.000 0.064 0.000 s 195.1 4.027e+04

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Summary


Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local Clock Frequency Offset -13.274 -13.185 -13.142 -12.850 -12.522 -12.473 -6.927 0.620 0.712 0.224 -12.830 ppm -1.993e+05 1.165e+07
Local Clock Time Offset -392.906 -8.119 -4.801 0.340 3.250 4.830 282.978 8.051 12.949 2.701 -0.008 µs -7.288 2281
Local RMS Frequency Jitter 0.675 1.630 2.167 4.296 7.352 8.972 1,563.584 5.185 7.342 8.304 4.547 ppb 123.1 1.797e+04
Local RMS Time Jitter 0.396 1.015 1.338 2.711 4.759 5.948 272.264 3.421 4.933 1.775 2.845 µs 68.64 7951
Server Jitter 132.163.97.5 7.471 13.313 18.541 35.943 63.143 547.289 3,332.128 44.602 533.976 216.527 56.968 µs 9.678 128.3
Server Jitter 132.246.11.229 0.020 0.046 0.083 0.234 1.210 2.643 3.421 1.127 2.597 0.444 0.368 ms 3.147 16.24
Server Jitter 134.84.84.84 1.690 2.577 3.693 8.049 18.968 30.886 148.255 15.275 28.309 9.306 9.805 µs 8.995 110.4
Server Jitter 204.9.54.119 0.003 0.004 0.006 0.010 0.017 1.299 3.454 0.011 1.295 0.271 0.038 ms 7.177 83.28
Server Jitter 2600:2600::99 (ntp1.wiktel.com) 3.376 6.407 9.229 19.778 35.339 438.680 453.108 26.110 432.273 45.825 25.289 µs 7.328 65.76
Server Jitter 2606:4700:f1::1 (time.cloudflare.com) 2.975 4.873 6.986 16.655 101.714 349.195 2,898.149 94.728 344.322 182.055 42.396 µs 9.709 138.1
Server Jitter 2606:4700:f1::123 (time.cloudflare.com) 2.555 5.184 6.649 15.394 86.770 533.631 2,895.625 80.121 528.447 204.334 43.444 µs 8.519 109.2
Server Jitter 2607:f128::50 6.544 12.090 16.230 33.228 70.024 300.481 1,113.768 53.794 288.391 73.902 43.236 µs 9.7 122
Server Jitter 2607:f388::123:2 (ntp2.doit.wisc.edu) 4.241 9.487 12.504 24.879 70.595 93.631 416.790 58.091 84.144 21.608 30.099 µs 8.184 117.2
Server Jitter SHM(1) 0.000 0.000 0.000 0.000 0.000 0.000 15.000 0.000 0.000 0.064 0.000 s 195.1 4.027e+04
Server Offset 132.163.97.5 -1.141 -1.121 -1.110 -1.072 2.231 2.264 5.375 3.342 3.385 0.914 -0.831 ms -8.901 23.54
Server Offset 132.246.11.229 -3.909 -1.104 -0.877 -0.759 -0.562 2.298 2.351 0.315 3.402 0.619 -0.675 ms -12.67 45.19
Server Offset 134.84.84.84 -74.395 -50.089 -35.462 -8.554 19.473 31.845 52.960 54.935 81.934 16.765 -7.972 µs -7.683 21.65
Server Offset 204.9.54.119 -0.913 -0.906 -0.902 -0.893 -0.880 2.565 2.575 0.022 3.470 0.624 -0.777 ms -12.88 36.95
Server Offset 2600:2600::99 (ntp1.wiktel.com) -376.899 -365.777 -359.463 -343.288 -327.734 -320.550 -314.291 31.729 45.227 9.772 -343.200 µs -4.724e+04 1.71e+06
Server Offset 2606:4700:f1::1 (time.cloudflare.com) -2.913 -2.219 -1.928 -0.326 -0.002 0.312 0.349 1.926 2.531 0.542 -0.422 ms -13.14 51.43
Server Offset 2606:4700:f1::123 (time.cloudflare.com) -2.919 -2.555 -0.525 -0.397 -0.106 0.305 0.610 0.419 2.860 0.402 -0.412 ms -18.29 95.39
Server Offset 2607:f128::50 698.625 722.144 740.867 781.588 818.361 837.301 856.804 77.494 115.157 23.738 780.725 µs 3.253e+04 1.04e+06
Server Offset 2607:f388::123:2 (ntp2.doit.wisc.edu) -216.559 -129.368 -86.723 -30.157 37.961 104.866 223.772 124.684 234.234 40.453 -27.998 µs -9.193 28.48
Server Offset SHM(1) -0.000 -0.000 -0.000 0.000 0.000 0.000 15.000 0.000 0.000 0.436 0.013 s 30.5 1052
Summary as CSV file


Glossary:

frequency offset:
The difference between the ntpd calculated frequency and the local system clock frequency (usually in parts per million, ppm)
jitter, dispersion:
The short term change in a value. NTP measures Local Time Jitter, Refclock Jitter, and Server Jitter in seconds. Local Frequency Jitter is in ppm or ppb.
kurtosis, Kurt:
The kurtosis of a random variable X is the fourth standardized moment and is a dimension-less ratio. ntpviz uses the Pearson's moment coefficient of kurtosis. A normal distribution has a kurtosis of three. NIST describes a kurtosis over three as "heavy tailed" and one under three as "light tailed".
ms, millisecond:
One thousandth of a second = 0.001 seconds, 1e-3 seconds
mu, mean:
The arithmetic mean: the sum of all the values divided by the number of values. The formula for mu is: "mu = (∑xi) / N". Where xi denotes the data points and N is the number of data points.
ns, nanosecond:
One billionth of a second, also one thousandth of a microsecond, 0.000000001 seconds and 1e-9 seconds.
percentile:
The value below which a given percentage of values fall.
ppb, parts per billion:
Ratio between two values. These following are all the same: 1 ppb, one in one billion, 1/1,000,000,000, 0.000,000,001, 1e-9 and 0.000,000,1%
ppm, parts per million:
Ratio between two values. These following are all the same: 1 ppm, one in one million, 1/1,000,000, 0.000,001, and 0.000,1%
‰, parts per thousand:
Ratio between two values. These following are all the same: 1 ‰. one in one thousand, 1/1,000, 0.001, and 0.1%
refclock:
Reference clock, a local GPS module or other local source of time.
remote clock:
Any clock reached over the network, LAN or WAN. Also called a peer or server.
time offset:
The difference between the ntpd calculated time and the local system clock's time. Also called phase offset.
σ, sigma:
Sigma denotes the standard deviation (SD) and is centered on the arithmetic mean of the data set. The SD is simply the square root of the variance of the data set. Two sigma is simply twice the standard deviation. Three sigma is three times sigma. Smaller is better.
The formula for sigma is: "σ = √[ ∑(xi-mu)^2 / N ]". Where xi denotes the data points and N is the number of data points.
skewness, Skew:
The skewness of a random variable X is the third standardized moment and is a dimension-less ratio. ntpviz uses the Pearson's moment coefficient of skewness. Wikipedia describes it best: "The qualitative interpretation of the skew is complicated and unintuitive."
A normal distribution has a skewness of zero.
upstream clock:
Any server or reference clock used as a source of time.
µs, us, microsecond:
One millionth of a second, also one thousandth of a millisecond, 0.000,001 seconds, and 1e-6 seconds.



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