NTPsec

ntpsec-72-hour-stats

Report generated: Tue Jul 7 05:02:11 2020 UTC
Start Time: Sat Jul 4 05:02:07 2020 UTC
End Time: Tue Jul 7 05:02:07 2020 UTC
Report published: Mon Jul 06 22:02:29 2020 PDT
Report Period: 3.0 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 -18.287 -2.543 -1.667 -0.004 1.425 1.953 5.411 3.092 4.496 1.125 -0.087 µs -6.205 34.26
Local Clock Frequency Offset -1.567 -1.563 -1.511 -0.951 -0.502 -0.481 -0.474 1.009 1.082 0.316 -0.965 ppm -79.11 375.7

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 0.148 0.233 0.283 0.427 0.669 0.883 6.188 0.386 0.650 0.216 0.454 µs 16.51 289.6

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 0.000 0.062 0.080 0.219 0.651 2.647 15.425 0.571 2.585 0.649 0.315 ppb 9.475 141.3

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 -18.287 -2.543 -1.667 -0.004 1.425 1.953 5.411 3.092 4.496 1.125 -0.087 µs -6.205 34.26

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 -1.567 -1.563 -1.511 -0.951 -0.502 -0.481 -0.474 1.009 1.082 0.316 -0.965 ppm -79.11 375.7
Temp ZONE0 61.224 61.762 62.300 65.528 68.756 68.756 69.294 6.456 6.994 1.989 65.492 °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 7.000 8.000 10.000 12.000 12.000 12.000 4.000 5.000 1.255 9.658 nSat 319.8 2276
TDOP 0.540 0.550 0.600 0.820 1.300 1.560 1.810 0.700 1.010 0.219 0.863 35.3 143.5

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 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 -1.525 -1.432 -1.310 0.049 0.127 0.241 0.705 1.437 1.672 0.427 -0.105 ms -8.043 30.5

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 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 -49.259 -1.442 -1.296 0.066 0.143 0.184 0.640 1.439 1.625 1.536 -0.073 ms -29.99 835

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 2001:1948:210:2::4

peer offset 2001:1948:210:2::4 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2001:1948:210:2::4 -3.440 -2.966 -2.467 -1.376 -0.056 0.510 0.898 2.411 3.475 0.724 -1.328 ms -31.09 113.6

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 2001:470:0:50::2 (clock.fmt.he.net)

peer offset 2001:470:0:50::2 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2001:470:0:50::2 (clock.fmt.he.net) 0.002 0.002 0.002 0.003 0.003 0.003 14.315 0.001 0.001 0.594 0.027 s 20.27 491.7

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 2001:470:e815::24 (pi4.rellim.com)

peer offset 2001:470:e815::24 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2001:470:e815::24 (pi4.rellim.com) 2.756 2.998 3.261 3.682 4.243 4.883 52.547 0.982 1.885 3.763 4.008 ms 12.22 150

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 0.086 1.916 2.275 2.641 3.104 3.532 14.584 0.829 1.616 0.555 2.675 ms 81.64 838.1

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 2405:fc00:0:1::123

peer offset 2405:fc00:0:1::123 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2405:fc00:0:1::123 1.836 2.313 2.789 3.861 5.347 5.725 6.496 2.557 3.412 0.827 3.872 ms 61.32 273.1

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 2604:a880:1:20::17:5001 (ntp1.glypnod.com)

peer offset 2604:a880:1:20::17:5001 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2604:a880:1:20::17:5001 (ntp1.glypnod.com) 1.728 2.030 2.172 2.547 3.006 3.317 4.779 0.835 1.287 0.269 2.565 ms 649 5797

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 2a03:b0c0:1:d0::1f9:f001 (ntp2.glypnod.com)

peer offset 2a03:b0c0:1:d0::1f9:f001 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2a03:b0c0:1:d0::1f9:f001 (ntp2.glypnod.com) -11.362 -7.077 -3.562 2.266 4.182 8.297 10.493 7.744 15.374 2.463 1.649 ms -2.166 8.937

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) -0.071 -0.058 -0.055 -0.049 -0.043 -0.041 14.651 0.012 0.017 0.041 -0.049 s 338.1 1.242e+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) -0.000 -0.000 -0.000 -0.000 0.000 0.000 14.700 0.000 0.000 0.112 0.001 s 127 1.664e+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 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 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 0.029 0.209 8.696 10.316 191.364 8.667 10.302 10.289 2.138 ms 11.99 208.1

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 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 0.018 0.036 0.165 8.682 9.710 140.077 8.645 9.692 5.275 1.571 ms 15.69 404.9

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 2001:1948:210:2::4

peer jitter 2001:1948:210:2::4 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2001:1948:210:2::4 0.000 0.248 0.333 1.609 9.934 28.293 249.154 9.601 28.044 12.792 3.820 ms 13.94 265.4

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 2001:470:0:50::2 (clock.fmt.he.net)

peer jitter 2001:470:0:50::2 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2001:470:0:50::2 (clock.fmt.he.net) 0.000 0.170 0.263 1.775 9.030 31.805 180.760 8.767 31.635 11.271 3.735 ms 11.35 177.4

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 2001:470:e815::24 (pi4.rellim.com)

peer jitter 2001:470:e815::24 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2001:470:e815::24 (pi4.rellim.com) 0.000 0.275 0.446 1.898 9.953 49.358 193.397 9.507 49.083 13.478 4.570 ms 8.645 113.2

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 0.000 0.246 0.394 1.828 12.062 80.014 215.329 11.668 79.768 16.413 5.370 ms 6.324 68.72

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 2405:fc00:0:1::123

peer jitter 2405:fc00:0:1::123 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2405:fc00:0:1::123 0.000 0.292 0.416 2.277 10.588 15.883 218.588 10.172 15.591 12.137 4.397 ms 12.02 202.8

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 2604:a880:1:20::17:5001 (ntp1.glypnod.com)

peer jitter 2604:a880:1:20::17:5001 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2604:a880:1:20::17:5001 (ntp1.glypnod.com) 0.000 0.228 0.345 1.528 9.150 45.509 209.641 8.805 45.281 15.321 4.245 ms 7.351 83.73

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 2a03:b0c0:1:d0::1f9:f001 (ntp2.glypnod.com)

peer jitter 2a03:b0c0:1:d0::1f9:f001 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2a03:b0c0:1:d0::1f9:f001 (ntp2.glypnod.com) 0.000 0.279 0.398 2.021 10.405 33.602 245.935 10.007 33.322 15.141 4.808 ms 10.34 151.8

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 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 0.000 0.000 0.001 0.003 0.006 14.696 0.003 0.006 0.066 0.002 s 158.4 2.849e+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.



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 0.154 0.212 0.415 0.870 1.256 13.402 0.658 1.102 0.362 0.474 µs 16.5 438

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 -1.567 -1.563 -1.511 -0.951 -0.502 -0.481 -0.474 1.009 1.082 0.316 -0.965 ppm -79.11 375.7
Local Clock Time Offset -18.287 -2.543 -1.667 -0.004 1.425 1.953 5.411 3.092 4.496 1.125 -0.087 µs -6.205 34.26
Local RMS Frequency Jitter 0.000 0.062 0.080 0.219 0.651 2.647 15.425 0.571 2.585 0.649 0.315 ppb 9.475 141.3
Local RMS Time Jitter 0.148 0.233 0.283 0.427 0.669 0.883 6.188 0.386 0.650 0.216 0.454 µs 16.51 289.6
Server Jitter 192.168.1.11 0.000 0.014 0.029 0.209 8.696 10.316 191.364 8.667 10.302 10.289 2.138 ms 11.99 208.1
Server Jitter 192.168.1.12 0.000 0.018 0.036 0.165 8.682 9.710 140.077 8.645 9.692 5.275 1.571 ms 15.69 404.9
Server Jitter 2001:1948:210:2::4 0.000 0.248 0.333 1.609 9.934 28.293 249.154 9.601 28.044 12.792 3.820 ms 13.94 265.4
Server Jitter 2001:470:0:50::2 (clock.fmt.he.net) 0.000 0.170 0.263 1.775 9.030 31.805 180.760 8.767 31.635 11.271 3.735 ms 11.35 177.4
Server Jitter 2001:470:e815::24 (pi4.rellim.com) 0.000 0.275 0.446 1.898 9.953 49.358 193.397 9.507 49.083 13.478 4.570 ms 8.645 113.2
Server Jitter 216.218.254.202 0.000 0.246 0.394 1.828 12.062 80.014 215.329 11.668 79.768 16.413 5.370 ms 6.324 68.72
Server Jitter 2405:fc00:0:1::123 0.000 0.292 0.416 2.277 10.588 15.883 218.588 10.172 15.591 12.137 4.397 ms 12.02 202.8
Server Jitter 2604:a880:1:20::17:5001 (ntp1.glypnod.com) 0.000 0.228 0.345 1.528 9.150 45.509 209.641 8.805 45.281 15.321 4.245 ms 7.351 83.73
Server Jitter 2a03:b0c0:1:d0::1f9:f001 (ntp2.glypnod.com) 0.000 0.279 0.398 2.021 10.405 33.602 245.935 10.007 33.322 15.141 4.808 ms 10.34 151.8
Server Jitter SHM(0) 0.000 0.000 0.000 0.001 0.003 0.006 14.696 0.003 0.006 0.066 0.002 s 158.4 2.849e+04
Server Jitter SHM(1) 0.000 0.154 0.212 0.415 0.870 1.256 13.402 0.658 1.102 0.362 0.474 µs 16.5 438
Server Offset 192.168.1.11 -1.525 -1.432 -1.310 0.049 0.127 0.241 0.705 1.437 1.672 0.427 -0.105 ms -8.043 30.5
Server Offset 192.168.1.12 -49.259 -1.442 -1.296 0.066 0.143 0.184 0.640 1.439 1.625 1.536 -0.073 ms -29.99 835
Server Offset 2001:1948:210:2::4 -3.440 -2.966 -2.467 -1.376 -0.056 0.510 0.898 2.411 3.475 0.724 -1.328 ms -31.09 113.6
Server Offset 2001:470:0:50::2 (clock.fmt.he.net) 0.002 0.002 0.002 0.003 0.003 0.003 14.315 0.001 0.001 0.594 0.027 s 20.27 491.7
Server Offset 2001:470:e815::24 (pi4.rellim.com) 2.756 2.998 3.261 3.682 4.243 4.883 52.547 0.982 1.885 3.763 4.008 ms 12.22 150
Server Offset 216.218.254.202 0.086 1.916 2.275 2.641 3.104 3.532 14.584 0.829 1.616 0.555 2.675 ms 81.64 838.1
Server Offset 2405:fc00:0:1::123 1.836 2.313 2.789 3.861 5.347 5.725 6.496 2.557 3.412 0.827 3.872 ms 61.32 273.1
Server Offset 2604:a880:1:20::17:5001 (ntp1.glypnod.com) 1.728 2.030 2.172 2.547 3.006 3.317 4.779 0.835 1.287 0.269 2.565 ms 649 5797
Server Offset 2a03:b0c0:1:d0::1f9:f001 (ntp2.glypnod.com) -11.362 -7.077 -3.562 2.266 4.182 8.297 10.493 7.744 15.374 2.463 1.649 ms -2.166 8.937
Server Offset SHM(0) -0.071 -0.058 -0.055 -0.049 -0.043 -0.041 14.651 0.012 0.017 0.041 -0.049 s 338.1 1.242e+05
Server Offset SHM(1) -0.000 -0.000 -0.000 -0.000 0.000 0.000 14.700 0.000 0.000 0.112 0.001 s 127 1.664e+04
TDOP 0.540 0.550 0.600 0.820 1.300 1.560 1.810 0.700 1.010 0.219 0.863 35.3 143.5
Temp ZONE0 61.224 61.762 62.300 65.528 68.756 68.756 69.294 6.456 6.994 1.989 65.492 °C
nSats 6.000 7.000 8.000 10.000 12.000 12.000 12.000 4.000 5.000 1.255 9.658 nSat 319.8 2276
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.



This page autogenerated by ntpviz, part of the NTPsec project
html 5    Valid CSS!