[ntp:questions] ref clock for network POP locations
Jeff W. Boote
boote at internet2.edu
Tue Sep 26 19:56:09 UTC 2006
I have some network locations where I have no way to access GPS or CDMA. But, I
would still like to have a very accurate time source. (I would like
sub-microsecond accuracy from NTPD if I can get it.) These locations are in
telco-hotels, so they are typically very well shielded making any broadcast
technology unworkable. (We are not using sonet - so getting time from there is
also not an option.)
I was thinking that it might be possible to get an oscillator to provide a PPS
signal, and then use a very well connected (possibly even a dedicated network
link with no router/switch) network peer as the preferred peer. Is this a
reasonable solution? Can anyone suggest anything better?
The PPS would need to be calibrated... Is the normal ntp calibration reasonable
for this? I would guess it depends on the oscillator...
If this is a reasonable solution, does anyone have recommendations for
oscillators? Most of the ones I have seen want a reference source of their own.
This of course does not work in my case...
P.S. I will happily add information to the wiki on this after figuring out how
to do it. (If?)
More information about the questions