Re: [Ntp] WGLC: draft-ietf-ntp-packet-timestamps

[Daniel Franke <[e-mail]>]

On Wed, Dec 19, 2018 at 3:26 PM Watson Ladd <[e-mail]> wrote:
> What you want is TAI which is in the spec. Why introduce a new kind of time? Why count days and seconds and have a strange multiple representation issue?
>
> UTC is UTC. It is defined by BIPM. Your timescale is not UTC. It is not a different timestamp format but a different timescale. Intercalcary nanoseconds need to be added in ways you have not defined. For one thing what's a day and when is midnight? Siderial, solar, or mean?
>
> If you want every second to be unique use TAI. That's what it is for.

I think you're confused. TAI, as defined by BIPM, is canonically
expressed as Gregorian date, hours, minutes, and seconds, but since
every day consists of exactly 86400 SI seconds, it can equivalently be
expressed as a real number of seconds since some fixed epoch. "What's
a day?" and "When is midnight?" are questions that BIPM will answer
for you. UTC is defined by the ITU
(https://www.itu.int/dms_pubrec/itu-r/rec/tf/R-REC-TF.460-6-200202-I!!PDF-E.pdf)
and is also canonically expressed as Gregorian date, hours, minutes,
and seconds, but days are sometimes 86401 SI seconds long; time time
half a second before the end of one of these days is 23:59:60.5.
Because of this variation in day length, you can't unambiguously
represent UTC as a scalar; you need separate fields for representing
date and time of day

Your accusation of introducing a new kind of time that is not UTC
should not be directed at me; it *should* be directed at virtually
every computer time standard currently out there, except for ISO 8601
which gets it right.