NTPsec

a-ntpsec-14-day-stats

Report generated: Thu Apr 2 03:05:48 2020 UTC
Start Time: Thu Mar 19 03:05:24 2020 UTC
End Time: Thu Apr 2 03:05:24 2020 UTC
Report published: Wed Apr 01 20:08:58 2020 PDT
Report Period: 14.0 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 -4.495 -1.243 -0.922 -0.016 0.946 1.317 1.976 1.868 2.560 0.597 -0.003 µs -4.002 9.65
Local Clock Frequency Offset -1.032 -1.008 -0.945 -0.780 -0.570 -0.525 -0.488 0.375 0.483 0.114 -0.760 ppm -471.7 3787

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 81.000 131.000 155.000 295.000 580.000 662.000 976.000 425.000 531.000 145.413 332.263 ns 6.439 17.06

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 24.000 35.000 47.000 139.000 256.000 310.000 1,628.000 209.000 275.000 66.811 143.211 10e-12 7.045 51.81

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 -4.495 -1.243 -0.922 -0.016 0.946 1.317 1.976 1.868 2.560 0.597 -0.003 µs -4.002 9.65

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 -1.032 -1.008 -0.945 -0.780 -0.570 -0.525 -0.488 0.375 0.483 0.114 -0.760 ppm -471.7 3787
Temp ZONE0 60.686 61.224 62.300 63.376 64.990 65.528 66.066 2.690 4.304 0.996 63.626 °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 6.000 6.000 7.000 8.000 11.000 11.000 11.000 4.000 5.000 1.519 8.365 nSat 105.4 543
TDOP 0.580 0.580 0.580 1.070 1.320 1.600 1.600 0.740 1.020 0.290 0.956 18.94 60.94

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. TDOP ranges from 1 to greater than 20. 1 denotes the highest possible confidence level. 2 to 5 is good. Greater than 20 means there will be significant inaccuracy and error.



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 -7.493 -5.541 -2.084 2.768 4.175 5.245 7.059 6.258 10.786 1.907 2.344 ms -1.578 7.661

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 137.190.2.4

peer offset 137.190.2.4 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 137.190.2.4 -43.092 -2.082 0.626 1.022 1.545 1.872 4.218 0.920 3.954 1.282 0.943 ms -17.95 453

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 -36.594 -5.140 1.668 6.305 11.140 14.912 18.512 9.472 20.052 3.468 6.152 ms 0.08178 28.99

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 192.168.1.11

peer offset 192.168.1.11 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 192.168.1.11 -3,046.379 -59.737 -39.835 20.079 80.636 100.230 323.598 120.471 159.967 46.147 21.435 µs -20.62 1252

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 192.168.1.12

peer offset 192.168.1.12 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 192.168.1.12 -229.385 -89.866 -68.410 11.013 66.178 76.071 185.042 134.588 165.937 44.171 4.081 µs -3.724 8.637

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 -5.531 -2.571 -2.102 -0.733 1.397 2.812 16.217 3.498 5.383 1.307 -0.588 ms -6.332 21.36

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 -3.961 1.327 1.543 1.948 2.901 3.574 9.876 1.358 2.247 0.562 2.041 ms 31.15 201.8

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 0.057 1.927 2.139 2.479 2.960 3.382 5.823 0.821 1.455 0.294 2.507 ms 451 3607

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 -0.395 2.040 2.238 2.574 3.035 3.504 4.529 0.797 1.464 0.273 2.598 ms 644.9 5742

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) -83.684 -62.018 -59.142 -52.711 -46.395 -44.790 -42.161 12.747 17.228 3.825 -52.743 ms -3280 4.917e+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(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) -4.496 -1.244 -0.923 -0.017 0.947 1.318 1.977 1.870 2.562 0.598 -0.003 µs -4.002 9.645

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 0.154 0.255 0.398 2.229 9.774 13.444 66.419 9.376 13.189 4.158 3.544 ms 4.906 56.53

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 137.190.2.4

peer jitter 137.190.2.4 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 137.190.2.4 0.095 0.196 0.303 1.694 9.692 14.067 219.853 9.389 13.871 6.401 3.285 ms 19.34 618.1

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 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 0.213 0.335 0.540 2.839 11.450 32.713 213.324 10.910 32.378 8.306 4.721 ms 14.35 345.4

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 192.168.1.11

peer jitter 192.168.1.11 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 192.168.1.11 0.000 0.014 0.024 0.117 8.657 9.511 92.896 8.633 9.497 3.104 1.282 ms 4.34 96.65

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 192.168.1.12

peer jitter 192.168.1.12 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 192.168.1.12 0.006 0.020 0.035 0.122 8.656 9.437 135.198 8.621 9.416 3.399 1.295 ms 11.62 429.9

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 0.000 0.247 0.434 2.363 10.823 15.755 83.117 10.389 15.508 4.222 3.999 ms 4.736 72.03

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 0.088 0.222 0.338 1.681 9.508 15.546 244.889 9.170 15.324 8.517 3.411 ms 16.12 381.1

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 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 0.120 0.221 0.350 1.738 9.441 13.071 211.786 9.091 12.849 7.249 3.352 ms 13.82 299.8

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 0.123 0.194 0.335 1.681 9.422 12.495 156.949 9.088 12.301 4.420 3.035 ms 14.19 459.7

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) 0.000 0.314 0.456 1.158 3.252 5.896 20.974 2.796 5.582 1.074 1.471 ms 3.843 21.36

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) 30.000 87.000 121.000 303.000 697.000 893.000 1,927.000 576.000 806.000 183.305 340.143 ns 4.281 13.07

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 -1.032 -1.008 -0.945 -0.780 -0.570 -0.525 -0.488 0.375 0.483 0.114 -0.760 ppm -471.7 3787
Local Clock Time Offset -4.495 -1.243 -0.922 -0.016 0.946 1.317 1.976 1.868 2.560 0.597 -0.003 µs -4.002 9.65
Local RMS Frequency Jitter 24.000 35.000 47.000 139.000 256.000 310.000 1,628.000 209.000 275.000 66.811 143.211 10e-12 7.045 51.81
Local RMS Time Jitter 81.000 131.000 155.000 295.000 580.000 662.000 976.000 425.000 531.000 145.413 332.263 ns 6.439 17.06
Server Jitter 104.131.155.175 0.154 0.255 0.398 2.229 9.774 13.444 66.419 9.376 13.189 4.158 3.544 ms 4.906 56.53
Server Jitter 137.190.2.4 0.095 0.196 0.303 1.694 9.692 14.067 219.853 9.389 13.871 6.401 3.285 ms 19.34 618.1
Server Jitter 178.62.68.79 0.213 0.335 0.540 2.839 11.450 32.713 213.324 10.910 32.378 8.306 4.721 ms 14.35 345.4
Server Jitter 192.168.1.11 0.000 0.014 0.024 0.117 8.657 9.511 92.896 8.633 9.497 3.104 1.282 ms 4.34 96.65
Server Jitter 192.168.1.12 0.006 0.020 0.035 0.122 8.656 9.437 135.198 8.621 9.416 3.399 1.295 ms 11.62 429.9
Server Jitter 203.123.48.219 0.000 0.247 0.434 2.363 10.823 15.755 83.117 10.389 15.508 4.222 3.999 ms 4.736 72.03
Server Jitter 204.17.205.24 0.088 0.222 0.338 1.681 9.508 15.546 244.889 9.170 15.324 8.517 3.411 ms 16.12 381.1
Server Jitter 216.218.192.202 0.120 0.221 0.350 1.738 9.441 13.071 211.786 9.091 12.849 7.249 3.352 ms 13.82 299.8
Server Jitter 216.218.254.202 0.123 0.194 0.335 1.681 9.422 12.495 156.949 9.088 12.301 4.420 3.035 ms 14.19 459.7
Server Jitter SHM(0) 0.000 0.314 0.456 1.158 3.252 5.896 20.974 2.796 5.582 1.074 1.471 ms 3.843 21.36
Server Jitter SHM(1) 30.000 87.000 121.000 303.000 697.000 893.000 1,927.000 576.000 806.000 183.305 340.143 ns 4.281 13.07
Server Offset 104.131.155.175 -7.493 -5.541 -2.084 2.768 4.175 5.245 7.059 6.258 10.786 1.907 2.344 ms -1.578 7.661
Server Offset 137.190.2.4 -43.092 -2.082 0.626 1.022 1.545 1.872 4.218 0.920 3.954 1.282 0.943 ms -17.95 453
Server Offset 178.62.68.79 -36.594 -5.140 1.668 6.305 11.140 14.912 18.512 9.472 20.052 3.468 6.152 ms 0.08178 28.99
Server Offset 192.168.1.11 -3,046.379 -59.737 -39.835 20.079 80.636 100.230 323.598 120.471 159.967 46.147 21.435 µs -20.62 1252
Server Offset 192.168.1.12 -229.385 -89.866 -68.410 11.013 66.178 76.071 185.042 134.588 165.937 44.171 4.081 µs -3.724 8.637
Server Offset 203.123.48.219 -5.531 -2.571 -2.102 -0.733 1.397 2.812 16.217 3.498 5.383 1.307 -0.588 ms -6.332 21.36
Server Offset 204.17.205.24 -3.961 1.327 1.543 1.948 2.901 3.574 9.876 1.358 2.247 0.562 2.041 ms 31.15 201.8
Server Offset 216.218.192.202 0.057 1.927 2.139 2.479 2.960 3.382 5.823 0.821 1.455 0.294 2.507 ms 451 3607
Server Offset 216.218.254.202 -0.395 2.040 2.238 2.574 3.035 3.504 4.529 0.797 1.464 0.273 2.598 ms 644.9 5742
Server Offset SHM(0) -83.684 -62.018 -59.142 -52.711 -46.395 -44.790 -42.161 12.747 17.228 3.825 -52.743 ms -3280 4.917e+04
Server Offset SHM(1) -4.496 -1.244 -0.923 -0.017 0.947 1.318 1.977 1.870 2.562 0.598 -0.003 µs -4.002 9.645
TDOP 0.580 0.580 0.580 1.070 1.320 1.600 1.600 0.740 1.020 0.290 0.956 18.94 60.94
Temp ZONE0 60.686 61.224 62.300 63.376 64.990 65.528 66.066 2.690 4.304 0.996 63.626 °C
nSats 6.000 6.000 7.000 8.000 11.000 11.000 11.000 4.000 5.000 1.519 8.365 nSat 105.4 543
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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