[ntp:questions] Poll timing

Danny Mayer mayer at ntp.isc.org
Thu Aug 16 11:53:56 UTC 2007

Jussi Kauppinen wrote:
> I'm interested in exact polling moments of NTP client. Consider for 
> example that I have polling interval set fixed to 16 seconds. Are the 
> requests sent instantly as the second of the clock of the client 
> changes? For example: previous polling time: 12.30:40:00, next polling 
> time: 12.30:56:00. I mean that polling happens always as xx.xx:xx:99 
> changes to xx.xx:xx:00. For example not like this: prev poll: 
> 12.30:40:78, next poll: 12.30:56:78.

No, it sends a client mode packet after the timer expires but it's also
doing other things and since it's also just another process on the
system it will never send it out at the exact moment. Nor does it need
to since the outgoing packet is always timestamped when it's sent. It
doesn't affect the results.

Why are you asking about this? Is there something deeper here?


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