[ntp:hackers] Server timestamps going backwards by up to 2 milliseconds
David J Taylor
david-taylor at blueyonder.co.uk
Wed Dec 23 10:04:53 UTC 2009
David,
On low precision systems, the effect of adding the "fuzz" in the low-order
bits of the timestamps can result in timestamps in the NTP packet returned
from the server going backwards by as much as two milliseconds (measured).
The transmit timestamp from the server can indicate a time earlier than
the receive timestamp. Is this really desirable? What effect might it
have on NTP clients which use such servers?
If there is a need for the "fuzz", should just the receive timestamp be
fuzzed, and the transmit reported as "fuzzed receive + epsilon", so that a
forward progression of time is maintained?
Thanks,
David
--
SatSignal software - quality software written to your requirements
Web: www.satsignal.eu
Email: davidtaylor at writeme.com
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