[ntp:questions] ntpd: time reset problem

Unruh unruh-spam at physics.ubc.ca
Wed Sep 16 01:04:11 UTC 2009


Dave Hart <davehart at gmail.com> writes:

>On Sep 14, 9:33=A0pm, Unruh wrote:
>> IF the latency is known to be symmetric ( which it is on an
>> interplanetary system) then large latency is no problem. If it is not
>> known to be symmetric and worse, both in and out latencies are variable,
>> then it is pretty well impossible.

>I believe the delays are asymmetric in large part due to vastly
>different data rates from the earth to the ship (high rate) vs from
>the ship (low rate).

No idea why that would make it assymetric. Light does not travel at a
different velocity simply because it is a crowd of other light ( or
radio waves). 


>Cheers,
>Dave Hart




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