[LEAPSECS] rubber seconds in Japan!

[M. Warner Losh]

In message: <20081229200904.GQ2263 at fysh.org>
            Zefram <zefram at fysh.org> writes:

: Steve Allen wrote:

: >100 of them, just before the leap

: 

: This is essentially the same technique as Markus Kuhn's UTC-SLS (UTC

: with Smoothed Leap Seconds), but over a shorter period.  One might well

: suppose that if they'd heard of UTC-SLS then they'd have used it, and so

: this is probably an independent invention.  Presumably they're working

: with the same objective: to provide a timescale that usually matches UTC

: exactly but also does not violate the fixed 60-seconds-per-minute model.

: 

: Interesting that they're only doing that for some users (those connecting

: by copper, apparently).  Users connecting by fibre get a visible (well,

: audible) leap.  Assumptions about the precision required by different

: classes of user?


I imagine that the fiber folks derive their clock from the fiber
carrier frequency, which can't be off by 1e-2.  The usual specs for
those start closer to 1e-12...

Warner