Re: [Cbor] I-D Action: draft-ietf-cbor-time-tag-04.txt

[Carsten Bormann <[e-mail]>]

On 2023-01-19, at 20:27, Vadim Goncharov <[e-mail]> wrote:
> 
> On Thu, 19 Jan 2023 00:18:25 +0100
> Carsten Bormann <[e-mail]> wrote:
> 
>>> What about the ability to encode a local time having an unspecified
>>> time zone? The C++ std::chrono::local_time duration is computed
>>> from the date time of day the same way as std::chrono::sys_time
>>> (POSIX), except that the time zone is unspecified instead of UTC.
>>> All that would be needed is a "Local" time scale to be added to the
>>> time scale registry. I already understand that you want to launch
>>> the time tag RFC with only the UTC and TAI time scales for now.  
>> 
>> As was discussed over in SEDATE as well, there even are some noises
>> that NTPv5 might adopt such a locally defined time scale (naysayers
>> notwithstanding that argue that NTP can only be used internet-wide
>> where such a locally defined time scale would not apply).
> 
> Sounds like not a very good idea…

That opinion depends a lot on perspectives.
If your job is to make NTP appliances that are used in intranets your perspective will be different from someone who tries to maintain pool.ntp.org.

> BTW, do they have changes in format
> to suport e.g. decimal?

they = NTP?
That certainly will stay binary.

> And what/where is SEDATE ?

WG charter:
https://datatracker.ietf.org/wg/sedate/about/

This is about adding extensibility to RFC 3339 date/time timestamps (the Internet profile of ISO 8601).

Let me cite:
>> Particularly when using times for interval, recurrence, or offset calculations,
>> it is necessary to know the context in which the timepoint exists. It would be
>> valuable to have a standard text serialisation format for this contextual data.
>> This working group will develop and publish a format meeting that requirement,
>> subject to the additional constraints described below.

Current draft:
https://www.ietf.org/archive/id/draft-ietf-sedate-datetime-extended-07.html
Just finished WGLC.

Example of another SDO we are cooperating with on this:
https://tc39.es/proposal-temporal/
https://tc39.es/proposal-temporal/docs/

Grüße, Carsten