On 1/21/11 2:26 PM, Robert E. Seastrom wrote:
Michael Holstein <michael.holstein@csuohio.edu> writes:
I'd be curious to see what effects (if any) those who use GPS-disciplined NTP references in Southeastern Georgia see from this experiment.
Aren't CDMA BTS clocked off GPS?
NTP isn't going to be the only "ripple".
Sure, and there are GPS-steered Rb clocks in telco-land too as well as a ton of stuff I don't know about yet until everyone else here chimes in; it's just that NTP is highly visible to NANOGers.
if your high quality stratum one time source isn't capable of free-running for a little while then it's not really high quality...
you can of course test this simply by disconnecting the antenna. if the dilution of precision gets sufficiently high or the boise floor climbs above the signal then it should fail the gps out of the mix. our symerticoms have upgraded ocxo and backup geographically distant ntp sources in the pool to account for localized gps failure...
I'm way to cheap to spring for the rubidum upgrade, the ocxo holdover is supposed to be 1ms a day.
The recomndation for a UTC timescales is to be within less than 1us of UTC at any given time. -P