NTPsec

B-ntpsec-1-hour-stats

Report generated: Fri May 29 07:01:11 2020 UTC
Start Time: Fri May 29 06:00:42 2020 UTC
End Time: Fri May 29 07:01:10 2020 UTC
Report published: Fri May 29 00:01:15 2020 PDT
Report Period: 0.0 days

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 -0.198 0.063 0.196 0.715 1.255 1.409 1.495 1.059 1.346 0.321 0.722 µs 5.71 14.44
Local Clock Frequency Offset -5.766 -5.765 -5.761 -5.722 -5.686 -5.684 -5.683 0.076 0.081 0.024 -5.722 ppm -1.36e+07 3.247e+09

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 165.000 174.000 184.000 257.000 376.000 397.000 435.000 192.000 223.000 60.351 268.179 ns 51.6 220

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 173.000 177.000 202.000 279.000 430.000 500.000 547.000 228.000 323.000 69.195 289.815 10e-12 43.06 182.6

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 -0.198 0.063 0.196 0.715 1.255 1.409 1.495 1.059 1.346 0.321 0.722 µs 5.71 14.44

The clock offsets of the local clock as a histogram.

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



Local Temperatures

local temps plot

Local temperatures. These will be site-specific depending upon what temperature sensors you collect data from. Temperature changes affect the local clock crystal frequency and stability. The math of how temperature changes frequency is complex, and also depends on crystal aging. So there is no easy way to correct for it in software. This is the single most important component of frequency drift.

The Local Temperatures are from field 3 from the tempstats log file.



Local Frequency/Temp

local freq temps plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local Clock Frequency Offset -5.766 -5.765 -5.761 -5.722 -5.686 -5.684 -5.683 0.076 0.081 0.024 -5.722 ppm -1.36e+07 3.247e+09
Temp ZONE0 62.300 62.300 62.300 62.838 63.376 63.376 63.376 1.076 1.076 0.360 62.910 °C

The frequency offsets and temperatures. Showing frequency offset (red, in parts per million, scale on right) and the temperatures.

These are field 4 (frequency) from the loopstats log file, and field 3 from the tempstats log file.



Local GPS

local gps plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
nSats 7.000 7.000 8.000 9.000 10.000 10.000 10.000 2.000 3.000 0.933 8.883 nSat 645.1 5716
TDOP 0.890 0.890 0.900 1.300 1.520 2.130 2.130 0.620 1.240 0.269 1.200 52.31 225.6

Local GPS. The Time Dilution of Precision (TDOP) is plotted in blue. The number of visible satellites (nSat) is plotted in red.

TDOP is field 3, and nSats is field 4, from the gpsd log file. The gpsd log file is created by the ntploggps program.

TDOP is a dimensionless error factor. Smaller numbers are better. TDOP ranges from 1 (ideal), 2 to 5 (good), to greater than 20 (poor). Some GNSS receivers report TDOP less than one which is theoretically impossible.



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 104.131.155.175

peer offset 104.131.155.175 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 104.131.155.175 1.414 1.414 1.414 1.747 2.060 2.060 2.060 0.646 0.646 0.189 1.714 ms 546 4594

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 169.229.128.134

peer offset 169.229.128.134 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 169.229.128.134 2.171 2.171 2.171 2.616 2.919 2.919 2.919 0.748 0.748 0.192 2.610 ms 2041 2.62e+04

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 178.62.68.79

peer offset 178.62.68.79 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 178.62.68.79 -1.712 -1.712 -1.712 0.580 10.372 10.372 10.372 12.084 12.084 5.241 3.080 ms -0.6998 1.548

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 192.168.1.10

peer offset 192.168.1.10 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 192.168.1.10 34.111 34.111 56.715 82.462 101.201 104.902 104.902 44.486 70.791 14.154 80.423 µs 116 602.4

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 203.123.48.219

peer offset 203.123.48.219 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 203.123.48.219 2.061 2.061 2.061 2.536 2.821 2.821 2.821 0.760 0.760 0.233 2.587 ms 1057 1.095e+04

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 204.17.205.24

peer offset 204.17.205.24 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 204.17.205.24 1.675 1.675 1.675 1.894 2.448 2.448 2.448 0.774 0.774 0.219 1.948 ms 519.5 4320

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 216.218.192.202

peer offset 216.218.192.202 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 216.218.192.202 1.777 1.777 1.777 2.487 2.864 2.864 2.864 1.086 1.086 0.265 2.411 ms 555.8 4692

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 216.218.254.202

peer offset 216.218.254.202 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 216.218.254.202 2.504 2.504 2.504 2.627 3.066 3.066 3.066 0.562 0.562 0.199 2.721 ms 2062 2.658e+04

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(0)

peer offset SHM(0) plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset SHM(0) -403.127 -387.161 -378.988 -351.459 -327.266 -319.274 -313.629 51.722 67.887 15.359 -351.808 ms -1.373e+04 3.3e+05

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) -0.199 0.064 0.197 0.716 1.256 1.410 1.496 1.059 1.346 0.321 0.723 µs 5.731 14.51

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 104.131.155.175

peer jitter 104.131.155.175 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 104.131.155.175 0.523 0.523 0.523 4.978 6.707 6.707 6.707 6.184 6.184 2.608 3.231 ms 0.8537 1.646

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 169.229.128.134

peer jitter 169.229.128.134 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 169.229.128.134 0.358 0.358 0.358 1.345 7.735 7.735 7.735 7.377 7.377 2.494 2.625 ms 1.29 2.876

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 178.62.68.79

peer jitter 178.62.68.79 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 178.62.68.79 2.414 2.414 2.414 3.111 9.034 9.034 9.034 6.620 6.620 2.970 4.853 ms 2.835 5.794

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 192.168.1.10

peer jitter 192.168.1.10 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 192.168.1.10 0.023 0.023 0.037 0.192 9.813 10.361 10.361 9.776 10.338 3.678 2.632 ms 0.1924 1.629

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 203.123.48.219

peer jitter 203.123.48.219 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 203.123.48.219 0.642 0.642 0.642 1.747 14.120 14.120 14.120 13.478 13.478 4.582 4.753 ms 0.9093 2.458

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 204.17.205.24

peer jitter 204.17.205.24 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 204.17.205.24 0.370 0.370 0.370 2.469 5.009 5.009 5.009 4.639 4.639 1.460 2.430 ms 2.565 5.525

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 216.218.192.202

peer jitter 216.218.192.202 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 216.218.192.202 0.467 0.467 0.467 1.997 7.553 7.553 7.553 7.086 7.086 2.101 2.290 ms 1.71 4.561

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 216.218.254.202

peer jitter 216.218.254.202 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 216.218.254.202 0.413 0.413 0.413 1.631 5.849 5.849 5.849 5.437 5.437 2.146 2.946 ms 1.557 2.792

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(0)

peer jitter SHM(0) plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter SHM(0) 2.199 3.544 5.124 9.733 18.758 23.886 40.846 13.633 20.343 4.380 10.551 ms 8.322 29.12

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) 91.000 118.000 136.000 261.000 538.000 633.000 741.000 402.000 515.000 122.128 289.530 ns 7.666 23.92

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 -5.766 -5.765 -5.761 -5.722 -5.686 -5.684 -5.683 0.076 0.081 0.024 -5.722 ppm -1.36e+07 3.247e+09
Local Clock Time Offset -0.198 0.063 0.196 0.715 1.255 1.409 1.495 1.059 1.346 0.321 0.722 µs 5.71 14.44
Local RMS Frequency Jitter 173.000 177.000 202.000 279.000 430.000 500.000 547.000 228.000 323.000 69.195 289.815 10e-12 43.06 182.6
Local RMS Time Jitter 165.000 174.000 184.000 257.000 376.000 397.000 435.000 192.000 223.000 60.351 268.179 ns 51.6 220
Server Jitter 104.131.155.175 0.523 0.523 0.523 4.978 6.707 6.707 6.707 6.184 6.184 2.608 3.231 ms 0.8537 1.646
Server Jitter 169.229.128.134 0.358 0.358 0.358 1.345 7.735 7.735 7.735 7.377 7.377 2.494 2.625 ms 1.29 2.876
Server Jitter 178.62.68.79 2.414 2.414 2.414 3.111 9.034 9.034 9.034 6.620 6.620 2.970 4.853 ms 2.835 5.794
Server Jitter 192.168.1.10 0.023 0.023 0.037 0.192 9.813 10.361 10.361 9.776 10.338 3.678 2.632 ms 0.1924 1.629
Server Jitter 203.123.48.219 0.642 0.642 0.642 1.747 14.120 14.120 14.120 13.478 13.478 4.582 4.753 ms 0.9093 2.458
Server Jitter 204.17.205.24 0.370 0.370 0.370 2.469 5.009 5.009 5.009 4.639 4.639 1.460 2.430 ms 2.565 5.525
Server Jitter 216.218.192.202 0.467 0.467 0.467 1.997 7.553 7.553 7.553 7.086 7.086 2.101 2.290 ms 1.71 4.561
Server Jitter 216.218.254.202 0.413 0.413 0.413 1.631 5.849 5.849 5.849 5.437 5.437 2.146 2.946 ms 1.557 2.792
Server Jitter SHM(0) 2.199 3.544 5.124 9.733 18.758 23.886 40.846 13.633 20.343 4.380 10.551 ms 8.322 29.12
Server Jitter SHM(1) 91.000 118.000 136.000 261.000 538.000 633.000 741.000 402.000 515.000 122.128 289.530 ns 7.666 23.92
Server Offset 104.131.155.175 1.414 1.414 1.414 1.747 2.060 2.060 2.060 0.646 0.646 0.189 1.714 ms 546 4594
Server Offset 169.229.128.134 2.171 2.171 2.171 2.616 2.919 2.919 2.919 0.748 0.748 0.192 2.610 ms 2041 2.62e+04
Server Offset 178.62.68.79 -1.712 -1.712 -1.712 0.580 10.372 10.372 10.372 12.084 12.084 5.241 3.080 ms -0.6998 1.548
Server Offset 192.168.1.10 34.111 34.111 56.715 82.462 101.201 104.902 104.902 44.486 70.791 14.154 80.423 µs 116 602.4
Server Offset 203.123.48.219 2.061 2.061 2.061 2.536 2.821 2.821 2.821 0.760 0.760 0.233 2.587 ms 1057 1.095e+04
Server Offset 204.17.205.24 1.675 1.675 1.675 1.894 2.448 2.448 2.448 0.774 0.774 0.219 1.948 ms 519.5 4320
Server Offset 216.218.192.202 1.777 1.777 1.777 2.487 2.864 2.864 2.864 1.086 1.086 0.265 2.411 ms 555.8 4692
Server Offset 216.218.254.202 2.504 2.504 2.504 2.627 3.066 3.066 3.066 0.562 0.562 0.199 2.721 ms 2062 2.658e+04
Server Offset SHM(0) -403.127 -387.161 -378.988 -351.459 -327.266 -319.274 -313.629 51.722 67.887 15.359 -351.808 ms -1.373e+04 3.3e+05
Server Offset SHM(1) -0.199 0.064 0.197 0.716 1.256 1.410 1.496 1.059 1.346 0.321 0.723 µs 5.731 14.51
TDOP 0.890 0.890 0.900 1.300 1.520 2.130 2.130 0.620 1.240 0.269 1.200 52.31 225.6
Temp ZONE0 62.300 62.300 62.300 62.838 63.376 63.376 63.376 1.076 1.076 0.360 62.910 °C
nSats 7.000 7.000 8.000 9.000 10.000 10.000 10.000 2.000 3.000 0.933 8.883 nSat 645.1 5716
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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