[time-nuts] "Selective availability" af accurate time for Apple users?

Paul tic-toc at bodosom.net
Thu Oct 22 23:36:00 EDT 2015

On Tue, Oct 20, 2015 at 3:09 PM, Paul <tic-toc at bodosom.net> wrote:

> Network connected iOS devices not paired with a watch use (s)ntp at large
> intervals rather than the mobile network or GPS.

I expect iOS 9 still has the post-iOS 4 behavior of doing an (s)NTP poll to
time.apple.com at multi-day intervals.  It happens rarely enough to be
unpleasant to track but I have seen a ntpdate/sntp style poll from an
iPad.  A phone paired with a watch polls time.apple.com at least daily and
does an NTP multi-packet exchange which would explain the relative accuracy.

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