[LEAPSECS] Synchronization requirement

[Gerard Ashton]

There have been requests on this list to gather requirements
for civil time keeping. I would like to suggest one. Anyone
who has ever participated in an EBay auction will have noticed
that all the savvy bidders wait to the very end to submit bids.
However, mismatches between the bidder's clock and EBay's clock
could cause some of these bidders to miss the bidding deadline.
I doubt this is an isolated example; my intuition is that there
are and will be many such instances where there are advantages
to waiting until a deadline approaches before acting.

It would be futile to try to regulate this at the microsecond
or nanosecond level. But I think a real requirement exists
that a person operating a keyboard or mouse be able to depend
on the civil time-of-day to within human reaction time,
which is often taken to be 0.1 s. This would make the current
civil time definitions inadequate, because at least one country,
the UK, specifies Greenwich Mean Time as their basis of civil time
and failed to address proposals to clarify whether this means
UT1 or UTC. Let me summarize my requirement:

   The legal definition of time shall be sufficiently
   unambiguous that those with adequate equipment will
   be able to determine the correct time to an accuracy
   of 0.1 s or better.

Such a requirement would also put those who require better
time accuracy that they are outside the realm of legally
defined time and need to negotiate an agreement with their
partners.

Gerry Ashton