Re: [art] Predictable Internet Time

[Nico Williams <[e-mail]>]

On Wed, Mar 29, 2017 at 04:53:01PM +0200, Philip Homburg wrote:
> >I know of no POSIX system with a cesium atomic clock.

The preceding bit about POSIX seconds being unable to be SI seconds
without an atomic clock speaks for itself.  Joe may be the only one who
believes that.

> >The issue is that POSIX really runs off of whatever local source of time
> >passage is available, and can (and does) drift from TAI on *each*
> >system. That drift can't be determined until your system tries to sync
> >with an external source (e.g., via NTP).

Which... most do.

> To be completely pedantic, a single cesium clock will also drift from TAI/UTC.
> 
> There is no such concept as being in sync with TAI without external
> corrections.

To be even more pedantic that may not be meaningfully possible or useful
or desirable due to being in an irregular orbit around Earth (e.g.,
frequently using thrusters to adjust it) or not in orbit around Earth,
and not on Earth.

This is not a helpful distraction.  It's wasting everyone else's time.
Also yours and mine.

Nico
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