NetBSD-Users archive   Re: ntp/ntpdate and NAT  On Tue, Jun 04,
2013 at 12:46:46PM -0400, Greg Troxel wrote: > Basically, NTP
(ntpd and ntpdate) assume that the mean of the outgoing > and
incoming local timestamps (in the local machine's time) is the
same > time as the mean of the remote machines incoming and
outgoing timestamps > (in the remote machine's time).  Equating
those leads to an estimated > offset.  Thanks for the
clarification.  > Also, ntpdate sends several packets.  If the
NAT is slow on outbound > setup, then the subsequent packets
should be faster.   The problem is that the NAT is not
regularily slow. We all know the example of a clock that is
always exactly one hour late: it is a precise clock since the
translation is known and constant. The node doing the NAT is a
"user" Windows workstation, and obviously (from the speed of a
remote connection when I'm connected to the server via a custom
vpn), depending on what the user or user software is doing at
the moment, this varies greatly (if a user