NTPsec

A-ntpsec-5-day-stats

Report generated: Wed Oct 23 20:18:11 2019 UTC
Start Time: Fri Oct 18 20:17:30 2019 UTC
End Time: Wed Oct 23 20:17:30 2019 UTC
Report published: Wed Oct 23 13:20:08 2019 PDT
Report Period: 5.0 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 -2,702.000 -855.000 -547.000 11.000 550.000 793.000 1,536.000 1,097.000 1,648.000 342.611 11.210 ns -4.098 12.16
Local Clock Frequency Offset -748.550 -744.553 -694.733 -552.139 -510.330 -502.945 -499.527 184.403 241.608 56.984 -571.062 ppb -1373 1.555e+04

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 58.000 96.000 112.000 163.000 233.000 272.000 894.000 121.000 176.000 39.000 166.573 ns 46.78 229

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 18.000 25.000 30.000 61.000 214.000 379.000 728.000 184.000 354.000 68.401 83.444 10e-12 3.734 19.57

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 -2,702.000 -855.000 -547.000 11.000 550.000 793.000 1,536.000 1,097.000 1,648.000 342.611 11.210 ns -4.098 12.16

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 -748.550 -744.553 -694.733 -552.139 -510.330 -502.945 -499.527 184.403 241.608 56.984 -571.062 ppb -1373 1.555e+04
Temp ZONE0 59.072 59.072 59.610 60.148 62.300 62.300 63.376 2.690 3.228 0.733 60.579 °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 5.000 7.000 7.000 9.000 11.000 12.000 12.000 4.000 5.000 1.282 9.363 nSat 269.4 1818
TDOP 0.500 0.560 0.600 0.830 1.410 1.690 3.660 0.810 1.130 0.263 0.891 21.89 83.71

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 -6.897 -0.931 0.565 2.291 4.815 12.027 201.249 4.250 12.958 14.786 3.529 ms 9.76 125.7

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 -10.988 -2.557 -0.064 5.880 9.279 10.675 135.619 9.344 13.232 7.237 5.401 ms 14 253

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 -3.927 -0.716 -0.257 0.006 0.166 0.489 200.958 0.423 1.206 3.669 0.098 ms 38.75 1867

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 -196.386 -1.146 -0.349 -0.031 0.470 1.457 188.626 0.819 2.603 4.653 -0.018 ms -13.07 1545

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 -1.564 -1.132 -0.509 3.369 7.953 8.965 24.858 8.461 10.097 2.673 3.767 ms 2.245 10.82

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 -2.790 0.294 1.109 1.718 2.749 3.828 11.877 1.640 3.534 0.735 1.804 ms 12.06 103.8

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 -4.786 1.646 2.037 2.523 3.492 4.559 8.037 1.455 2.913 0.629 2.608 ms 40.12 189.7

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 -5.944 1.472 2.068 2.502 3.437 4.317 17.542 1.369 2.844 0.727 2.603 ms 32.54 361.5

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) -79.209 -62.916 -60.247 -52.484 -45.222 -43.258 -40.562 15.026 19.658 4.595 -52.531 ms -1959 2.483e+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) -2,703.000 -856.000 -548.000 12.000 551.000 794.000 1,537.000 1,099.000 1,650.000 343.358 11.237 ns -4.097 12.14

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 0.000 0.000 0.000 2.090 75.664 163.083 202.939 75.664 163.083 30.670 13.436 ms 1.495 9.936

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 0.000 0.780 1.377 4.053 85.113 140.328 153.341 83.736 139.548 32.296 18.996 ms 0.7355 3.921

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 0.102 0.206 1.300 107.355 151.008 353.194 107.149 150.906 43.018 28.387 ms 0.3555 3.738

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 0.000 0.122 0.235 1.274 106.578 157.459 317.480 106.344 157.337 40.002 21.884 ms 0.7648 6.232

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 0.213 0.547 0.907 3.866 93.997 131.998 187.071 93.090 131.450 33.857 21.390 ms 0.6128 3.504

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 0.236 0.382 0.693 2.794 96.927 139.321 194.840 96.234 138.940 35.074 20.741 ms 0.5729 3.727

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 0.262 0.395 0.738 2.858 90.583 156.290 180.542 89.845 155.895 35.036 19.778 ms 0.6714 4.2

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 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 0.191 0.423 0.693 3.076 107.394 142.107 186.082 106.701 141.684 37.519 22.723 ms 0.4673 3.044

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) 0.063 0.333 0.481 1.185 3.036 5.057 16.134 2.555 4.724 0.931 1.426 ms 4.248 22.99

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) 27.000 62.000 84.000 161.000 345.000 477.000 2,371.000 261.000 415.000 89.332 181.253 ns 7.062 49.48

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 -748.550 -744.553 -694.733 -552.139 -510.330 -502.945 -499.527 184.403 241.608 56.984 -571.062 ppb -1373 1.555e+04
Local Clock Time Offset -2,702.000 -855.000 -547.000 11.000 550.000 793.000 1,536.000 1,097.000 1,648.000 342.611 11.210 ns -4.098 12.16
Local RMS Frequency Jitter 18.000 25.000 30.000 61.000 214.000 379.000 728.000 184.000 354.000 68.401 83.444 10e-12 3.734 19.57
Local RMS Time Jitter 58.000 96.000 112.000 163.000 233.000 272.000 894.000 121.000 176.000 39.000 166.573 ns 46.78 229
Server Jitter 104.131.155.175 0.000 0.000 0.000 2.090 75.664 163.083 202.939 75.664 163.083 30.670 13.436 ms 1.495 9.936
Server Jitter 178.62.68.79 0.000 0.780 1.377 4.053 85.113 140.328 153.341 83.736 139.548 32.296 18.996 ms 0.7355 3.921
Server Jitter 192.168.1.11 0.000 0.102 0.206 1.300 107.355 151.008 353.194 107.149 150.906 43.018 28.387 ms 0.3555 3.738
Server Jitter 192.168.1.12 0.000 0.122 0.235 1.274 106.578 157.459 317.480 106.344 157.337 40.002 21.884 ms 0.7648 6.232
Server Jitter 203.123.48.219 0.213 0.547 0.907 3.866 93.997 131.998 187.071 93.090 131.450 33.857 21.390 ms 0.6128 3.504
Server Jitter 204.17.205.24 0.236 0.382 0.693 2.794 96.927 139.321 194.840 96.234 138.940 35.074 20.741 ms 0.5729 3.727
Server Jitter 216.218.192.202 0.262 0.395 0.738 2.858 90.583 156.290 180.542 89.845 155.895 35.036 19.778 ms 0.6714 4.2
Server Jitter 216.218.254.202 0.191 0.423 0.693 3.076 107.394 142.107 186.082 106.701 141.684 37.519 22.723 ms 0.4673 3.044
Server Jitter SHM(0) 0.063 0.333 0.481 1.185 3.036 5.057 16.134 2.555 4.724 0.931 1.426 ms 4.248 22.99
Server Jitter SHM(1) 27.000 62.000 84.000 161.000 345.000 477.000 2,371.000 261.000 415.000 89.332 181.253 ns 7.062 49.48
Server Offset 104.131.155.175 -6.897 -0.931 0.565 2.291 4.815 12.027 201.249 4.250 12.958 14.786 3.529 ms 9.76 125.7
Server Offset 178.62.68.79 -10.988 -2.557 -0.064 5.880 9.279 10.675 135.619 9.344 13.232 7.237 5.401 ms 14 253
Server Offset 192.168.1.11 -3.927 -0.716 -0.257 0.006 0.166 0.489 200.958 0.423 1.206 3.669 0.098 ms 38.75 1867
Server Offset 192.168.1.12 -196.386 -1.146 -0.349 -0.031 0.470 1.457 188.626 0.819 2.603 4.653 -0.018 ms -13.07 1545
Server Offset 203.123.48.219 -1.564 -1.132 -0.509 3.369 7.953 8.965 24.858 8.461 10.097 2.673 3.767 ms 2.245 10.82
Server Offset 204.17.205.24 -2.790 0.294 1.109 1.718 2.749 3.828 11.877 1.640 3.534 0.735 1.804 ms 12.06 103.8
Server Offset 216.218.192.202 -4.786 1.646 2.037 2.523 3.492 4.559 8.037 1.455 2.913 0.629 2.608 ms 40.12 189.7
Server Offset 216.218.254.202 -5.944 1.472 2.068 2.502 3.437 4.317 17.542 1.369 2.844 0.727 2.603 ms 32.54 361.5
Server Offset SHM(0) -79.209 -62.916 -60.247 -52.484 -45.222 -43.258 -40.562 15.026 19.658 4.595 -52.531 ms -1959 2.483e+04
Server Offset SHM(1) -2,703.000 -856.000 -548.000 12.000 551.000 794.000 1,537.000 1,099.000 1,650.000 343.358 11.237 ns -4.097 12.14
TDOP 0.500 0.560 0.600 0.830 1.410 1.690 3.660 0.810 1.130 0.263 0.891 21.89 83.71
Temp ZONE0 59.072 59.072 59.610 60.148 62.300 62.300 63.376 2.690 3.228 0.733 60.579 °C
nSats 5.000 7.000 7.000 9.000 11.000 12.000 12.000 4.000 5.000 1.282 9.363 nSat 269.4 1818
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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