[ntpwg] Comments on NTP draft -06

[Rob Seaman]

To expand on Steve's comments, note:

1) Leap seconds have indeed also been issued at the end of June (but  
not 2007).

2) Just announced, there will be NO leap second at the end of  
December 2007.

3) Current IERS policy limits the introduction of leap seconds to the  
end of June and December, but the UTC standard (good for many  
centuries yet) has always been the end of any month.

See:  http://hpiers.obspm.fr/iers/bul/bulc/bulletinc.dat

Rob Seaman
NOAO
-----

On Jun 28, 2007, at 9:12 AM, Steve Allen wrote:

> On Thu 2007-06-28T10:11:49 -0400, Danny Mayer hath writ:
>>>    LI Leap Indicator (leap): 2-bit integer warning of an  
>>> impending leap
>>>    second to be inserted or deleted in the last minute of the  
>>> current
>>>    month with values defined in Figure 10.
>>>
>>>            +------- 
>>> +-------------------------------------------------+
>>>            | Value |  
>>> Meaning                                         |
>>>            +------- 
>>> +-------------------------------------------------+
>>>            | 0     | no  
>>> warning                                      |
>>>            | 1     | last minute of the day has 61  
>>> seconds           |
>>>            | 2     | last minute of the day has 59  
>>> seconds           |
>>> SB> surely last minute of the last day of the month has X seconds?
>>
>> Not exactly. It's actually the last day of a specific quarter  
>> though I
>> don't think it's ever happened yet on any day but the last day of  
>> the year.
>
> No, not the quarter.  The text is right to use "month".  ITU-R TF.460
> allows for a leap second on the last day of *any* month.  That's
> another point in favor of including a reference to the official
> document.
>
> Perhaps the original point was that when the LI is 0 then the last
> minute of the month should default to 60 seconds?
>
> --
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