[LEAPSECS] private smear goes public

[Stephen Scott]

Hello Brooks, Stephen;

What's all this discussion about precision?

The smear has tossed the precision of the second SI out the window.
This is totally unacceptable for an application that requires a precise 
and stable frequency reference (telecommunications and broadcast for 
example).

Further, this is not the only smear algorithm.
A proliferation of smears could be the best reason for getting rid of 
the leap second.

The time community is not monolithic and there are different 
requirements of users.
No single approach is likely to satisfy all.
There is a requirement for a minimal set of standardized approaches.

-Stephen


On 2016-12-01 12:39, Brooks Harris wrote:
> Hi Stephen,
> On 2016-12-01 02:49 AM, Stephen Colebourne wrote:
>> More details on the developer site:
>> https://developers.google.com/time/
>>
>> Notably this page:
>> https://developers.google.com/time/smear
>>
>> which include "Our proposed standard smear" - "We would like to
>> propose to the community, as the best practice for leap seconds in the
>> future, a 24-hour linear smear from noon to noon UTC"
>>
>> Hip hip hooray! De facto standards for the win!
>>
>> Stephen
> Ah, this is good. I'd missed that page yesterday.
>
> I might suggest you good go a little further.
>
> You say "Each second of time marked by Google's servers will be about 
> 13.9 μs longer than an SI second. "
>
> Some developers may probably need to know exactly, or as exactly as 
> possible, the ratio.
>
> If I've got this right:
>
> 20 hours = 20 * 60 * 60 = 72000 seconds
> Plus the Leap Second = 72001 second
> So the ratio is 72001 / 72000 = 1.000013889 (rounded to 10-9th 
> precision, nanoseconds)
> This a repeating decimal number which may be denoted 1.000013(8).
> Applications should be careful to provide adequate precision for the 
> purpose.
>
> -Brooks
>
>
>
>
>
>
>>
>>
>> On 30 November 2016 at 21:05, Tom Van Baak <tvb at leapsecond.com> wrote:
>>> I'm surprised no one has posted this news yet:
>>>
>>> "Making every (leap) second count with our new public NTP servers"
>>> https://cloudplatform.googleblog.com/2016/11/making-every-leap-second-count-with-our-new-public-NTP-servers.html 
>>>
>>>
>>> /tvb
>>>
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>>
>>
>
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