[LEAPSECS] Cost: getting rid of GMT & discontinuing leap seconds

Joe Gwinn joegwinn at comcast.net
Sun Oct 24 21:48:21 EDT 2010

At 7:30 PM -0600 10/24/10, Warner Losh wrote:

> > I asked:


>> >> What coherent system design process led the engineers to select

>>UTC in spite of the existence of leap seconds?


>> Warner Losh asserted:


>> > UTC is the only game in town.


>> The foundation of civil time is universal time, that is - mean solar

>> time. UTC is a widely available realization of universal time.

>> Other timescales are all around.


>Can you point to one that's broadcast, in real time, around the planet

>like UTC is? GPS is broadcast, but nobody does time stamping in GPS,

>and it lacks the force of law that UTC has.

Actually, many realtime systems use GPS Time, precisely to avoid
leapsecond follies.

>And what are these other time scales available today?


>> > GPS time is weird, as is TAI time.


>> GPS time is widely available. NTP, for instance, provides proof of

>> concept that GPS is usable (weird or not).


>The NTP standard mandates UTC time. NTP recovers UTC time from GPS

>time and broadcasts that.

Yes, but we lie to NTP, and it's none the wiser. There are no
reports of the NTP Police crashing in through the windows, guns
blazing, to enforce RFC-1305 or successors.

Joe Gwinn

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