On Jan 21, 2011, at 1:45 PM, Gary Buhrmaster wrote: >> NTP isn't going to be the only "ripple". > > Most of the "brand name" GPS NTP solutions have a clock > with is more than stable enough to survive without GPS > lock for 45 minutes(*). Some of the more expensive units with > temperature controlled oscillators have hold times in the > many weeks. My guess is that the NTP ripples will be > limited to those NTP servers just (or recently) booted > which have not yet achieved a stable clock state. > > Gary > > (*) This presumes that this test results in loss of signal > lock, and not intentionally injected false information.
Loss of lock is a non-issue. However, the tests they are doing do not necessarily cause loss of lock. Sometimes, instead, they give you a wrong enough time to insure that your navigational fix is off by, well, enough to guarantee that you don't hit what you're aiming at. Owen
