NTPsec

C-ntpsec-1-hour-stats

Report generated: Thu Aug 13 06:01:09 2020 UTC
Start Time: Thu Aug 13 05:00:41 2020 UTC
End Time: Thu Aug 13 06:01:09 2020 UTC
Report published: Wed Aug 12 23:01:17 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 -1,203.000 -775.000 -644.000 -176.000 291.000 542.000 654.000 935.000 1,317.000 296.469 -159.352 ns -8.399 24.3
Local Clock Frequency Offset -5.244 -5.244 -5.244 -5.238 -5.236 -5.235 -5.235 0.0075 0.0084 0.0024 -5.239 ppm -1.079e+10 2.384e+13

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 125.000 132.000 147.000 195.000 279.000 348.000 372.000 132.000 216.000 42.797 202.604 ns 64.42 300.3

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 38.000 41.000 49.000 75.000 124.000 161.000 164.000 75.000 120.000 24.756 79.520 10e-12 18.4 65.46

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 -1,203.000 -775.000 -644.000 -176.000 291.000 542.000 654.000 935.000 1,317.000 296.469 -159.352 ns -8.399 24.3

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 -5.244 -5.244 -5.244 -5.238 -5.236 -5.235 -5.235 0.0075 0.0084 0.0024 -5.239 ppm -1.079e+10 2.384e+13
Temp ZONE0 59.072 59.072 59.072 59.610 60.148 60.148 60.148 1.076 1.076 0.433 59.682 °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 8.000 8.000 8.000 8.000 10.000 10.000 10.000 2.000 2.000 0.826 8.683 nSat 888.3 8736
TDOP 0.650 0.650 0.660 1.100 1.360 1.370 1.370 0.700 0.720 0.269 1.024 30.46 109.3

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 162.159.200.1

peer offset 162.159.200.1 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 162.159.200.1 1.242 1.242 1.242 2.084 3.624 3.624 3.624 2.382 2.382 0.665 2.292 ms 22.47 78.99

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 173.11.101.155

peer offset 173.11.101.155 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 173.11.101.155 -0.005 -0.005 -0.005 0.878 1.726 1.726 1.726 1.731 1.731 0.527 0.848 ms 1.877 3.995

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 61.428 61.428 99.596 166.460 222.584 231.684 231.684 122.988 170.256 36.316 160.056 µs 49.47 203.3

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 204.123.2.5

peer offset 204.123.2.5 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 204.123.2.5 2.567 2.567 2.567 2.619 3.189 3.189 3.189 0.622 0.622 0.234 2.731 ms 1244 1.364e+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 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 4.072 4.072 4.072 4.953 6.222 6.222 6.222 2.150 2.150 0.511 4.976 ms 695.1 6330

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) 2.473 2.473 2.473 3.272 4.947 4.947 4.947 2.474 2.474 0.762 3.624 ms 64.65 292.4

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 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) 1.376 1.376 1.376 1.837 3.159 3.159 3.159 1.782 1.782 0.513 2.036 ms 35.88 143.1

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 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) -60.349 -58.096 -57.036 -52.236 -46.824 -45.962 -45.633 10.212 12.134 3.148 -52.197 ms -5486 9.737e+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) -1,204.000 -775.000 -645.000 -177.000 292.000 543.000 655.000 937.000 1,318.000 297.145 -159.700 ns -8.394 24.26

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 162.159.200.1

peer jitter 162.159.200.1 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 162.159.200.1 1.919 1.919 1.919 8.805 23.941 23.941 23.941 22.022 22.022 6.678 10.370 ms 2.268 5.086

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 173.11.101.155

peer jitter 173.11.101.155 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 173.11.101.155 1.390 1.390 1.390 2.876 8.877 8.877 8.877 7.487 7.487 2.815 4.120 ms 2.277 4.74

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 0.034 0.034 0.058 0.424 8.990 9.035 9.035 8.932 9.001 3.135 2.219 ms 0.4013 2.128

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 204.123.2.5

peer jitter 204.123.2.5 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 204.123.2.5 1.244 1.244 1.244 2.526 5.326 5.326 5.326 4.083 4.083 1.734 3.245 ms 3.522 7.242

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 1.554 1.554 1.554 5.625 8.815 8.815 8.815 7.260 7.260 2.524 5.229 ms 4.458 9.928

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) 0.859 0.859 0.859 2.410 15.152 15.152 15.152 14.292 14.292 5.602 6.154 ms 0.9316 1.925

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) 1.143 1.143 1.143 3.443 9.700 9.700 9.700 8.557 8.557 2.896 4.788 ms 2.891 6.329

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) 0.149 0.226 0.346 0.941 2.907 5.098 5.933 2.561 4.872 0.924 1.190 ms 3.307 13.72

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 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) 81.000 82.000 117.000 261.000 507.000 771.000 878.000 390.000 689.000 131.728 280.383 ns 6.128 20.96

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 -5.244 -5.244 -5.244 -5.238 -5.236 -5.235 -5.235 0.0075 0.0084 0.0024 -5.239 ppm -1.079e+10 2.384e+13
Local Clock Time Offset -1,203.000 -775.000 -644.000 -176.000 291.000 542.000 654.000 935.000 1,317.000 296.469 -159.352 ns -8.399 24.3
Local RMS Frequency Jitter 38.000 41.000 49.000 75.000 124.000 161.000 164.000 75.000 120.000 24.756 79.520 10e-12 18.4 65.46
Local RMS Time Jitter 125.000 132.000 147.000 195.000 279.000 348.000 372.000 132.000 216.000 42.797 202.604 ns 64.42 300.3
Server Jitter 162.159.200.1 1.919 1.919 1.919 8.805 23.941 23.941 23.941 22.022 22.022 6.678 10.370 ms 2.268 5.086
Server Jitter 173.11.101.155 1.390 1.390 1.390 2.876 8.877 8.877 8.877 7.487 7.487 2.815 4.120 ms 2.277 4.74
Server Jitter 192.168.1.10 0.034 0.034 0.058 0.424 8.990 9.035 9.035 8.932 9.001 3.135 2.219 ms 0.4013 2.128
Server Jitter 204.123.2.5 1.244 1.244 1.244 2.526 5.326 5.326 5.326 4.083 4.083 1.734 3.245 ms 3.522 7.242
Server Jitter 2405:fc00:0:1::123 1.554 1.554 1.554 5.625 8.815 8.815 8.815 7.260 7.260 2.524 5.229 ms 4.458 9.928
Server Jitter 2604:a880:1:20::17:5001 (ntp1.glypnod.com) 0.859 0.859 0.859 2.410 15.152 15.152 15.152 14.292 14.292 5.602 6.154 ms 0.9316 1.925
Server Jitter 2a03:b0c0:1:d0::1f9:f001 (ntp2.glypnod.com) 1.143 1.143 1.143 3.443 9.700 9.700 9.700 8.557 8.557 2.896 4.788 ms 2.891 6.329
Server Jitter SHM(0) 0.149 0.226 0.346 0.941 2.907 5.098 5.933 2.561 4.872 0.924 1.190 ms 3.307 13.72
Server Jitter SHM(1) 81.000 82.000 117.000 261.000 507.000 771.000 878.000 390.000 689.000 131.728 280.383 ns 6.128 20.96
Server Offset 162.159.200.1 1.242 1.242 1.242 2.084 3.624 3.624 3.624 2.382 2.382 0.665 2.292 ms 22.47 78.99
Server Offset 173.11.101.155 -0.005 -0.005 -0.005 0.878 1.726 1.726 1.726 1.731 1.731 0.527 0.848 ms 1.877 3.995
Server Offset 192.168.1.10 61.428 61.428 99.596 166.460 222.584 231.684 231.684 122.988 170.256 36.316 160.056 µs 49.47 203.3
Server Offset 204.123.2.5 2.567 2.567 2.567 2.619 3.189 3.189 3.189 0.622 0.622 0.234 2.731 ms 1244 1.364e+04
Server Offset 2405:fc00:0:1::123 4.072 4.072 4.072 4.953 6.222 6.222 6.222 2.150 2.150 0.511 4.976 ms 695.1 6330
Server Offset 2604:a880:1:20::17:5001 (ntp1.glypnod.com) 2.473 2.473 2.473 3.272 4.947 4.947 4.947 2.474 2.474 0.762 3.624 ms 64.65 292.4
Server Offset 2a03:b0c0:1:d0::1f9:f001 (ntp2.glypnod.com) 1.376 1.376 1.376 1.837 3.159 3.159 3.159 1.782 1.782 0.513 2.036 ms 35.88 143.1
Server Offset SHM(0) -60.349 -58.096 -57.036 -52.236 -46.824 -45.962 -45.633 10.212 12.134 3.148 -52.197 ms -5486 9.737e+04
Server Offset SHM(1) -1,204.000 -775.000 -645.000 -177.000 292.000 543.000 655.000 937.000 1,318.000 297.145 -159.700 ns -8.394 24.26
TDOP 0.650 0.650 0.660 1.100 1.360 1.370 1.370 0.700 0.720 0.269 1.024 30.46 109.3
Temp ZONE0 59.072 59.072 59.072 59.610 60.148 60.148 60.148 1.076 1.076 0.433 59.682 °C
nSats 8.000 8.000 8.000 8.000 10.000 10.000 10.000 2.000 2.000 0.826 8.683 nSat 888.3 8736
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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