Subject: Re: Last Call: Date and Time on the Internet: Timestamps to Proposed Standard

From: Keith Moore <[email-masked]>
Date: Fri, 09 Nov 2001 17:16:09 -0500

basically I approve of publication of this document, with the following
caveat about scope

This representation is appropriate for dates and times for which the 
GMT offset as of the date and time specified is reliably known.  The
is usually the case for noting the current time (timestamping), or
representing the times of events in the past or the near future.

However, many events are actually specified relative to a particular 
timezone, and timezone offsets occasionally change with little advance
warning.  As such, this representation may not be sufficient for 
specifying dates and times of some kinds of events, particularly
future events.

In such cases it is necessary to include a representation of the timezone
(not merely the GMT offset) along with the date of the event.  This
specification does not provide such a facility, and is therefore
inappropriate for representation of (for example) events on a calendar.

Keith

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From: Joe Abley <[email-masked]>
Date: Fri, 9 Nov 2001 17:59:07 -0500

> inappropriate for representation of (for example) events on a calendar.

Is this not covered in section 1?

  o  All times expressed have a stated relationship (offset) to
     Coordinated Universal Time (UTC).  (This is distinct from some
     usage in scheduling applications where a local time and location
     may be known, but the actual relationship to UTC may be dependent
     on the unknown or unknowable actions of politicians or
     administrators.  The UTC time corresponding to 17:00 on 23rd March
     2005 in New York may depend on administrative decisions about
     daylight savings time.  This specification steers well clear of
     such considerations.)

Joe

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From: Keith Moore <[email-masked]>
Date: Fri, 09 Nov 2001 19:12:26 -0500

>      daylight savings time.  This specification steers well clear of

yes, that appears to be sufficient.  sorry I missed it.

Keith

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From: Frank Strauss <[email-masked]>
Date: 09 Nov 2001 23:48:18 +0100

Hi!

The IESG writes:

> The IESG has received a request from the Instant Messaging and Presence
> Protocol Working Group to consider Date and Time on the Internet:
> Timestamps <draft-ietf-impp-datetime-05.txt> as a Proposed Standard.

> The IESG plans to make a decision in the next few weeks, and solicits
> final comments on this action.  Please send any comments to the
> [email-masked] or [email-masked] mailing lists by November 23, 2001.

> Files can be obtained via
> http://www.ietf.org/internet-drafts/draft-ietf-impp-datetime-05.txt

I like to see this document and thank the authors for this piece of work!

I have two comments:

1. I've used Harald Alvestrand's abfn-parser to check the two grammars
   (the main one, and the one in Appendix A). The second one uses the
   token `date-time' which is only defined in the other grammer. I guess,
   this should be fixed.

2. I don't like to read things like this in a standards track document
   (Appendix A):

      This information is based on the 1988 version of ISO 8601.
      There may be some changes in the 2000 revision.  [...]  This is
      informational only and may contain errors.

   I understand, that this Appendix is just informational. However, under
   the mentioned conditions, I wonder what the purpose of this Appendix
   is. To avoid people refering to it, I would suggest to simply remove it.
   But I would prefer to see the Appendix keep part of the document and
   ensured that the contents are correct and up to date, before it enters
   the standards track.

 -frank

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From: Doug Royer <[email-masked]>
Date: Fri, 09 Nov 2001 16:35:59 -0700

Why not just specify that dates/times are RFC2445 compliant?
The calsch WG spent a long time debating these issues.

In addition the date-time format used in RFC2445 is also
ISO-8601 based.

In addition the calsch WG has a plan (don't laugh too hard)
for the usage of time zones. This draft only mentions they exist.

Why does there need to be another date-time standard?
Why did this not go through the calsch working group (at least
cc the working group before final proposal?). This draft
acknowledges the calsch WG, but the chairs (I called Pat) never
saw this - nor did I. Was it sent and debated as assumed by
reading the acknowledgements?

   6. Acknowledgements

      ... Thanks are also due
      to participants of the IETF Calendaring/Scheduling working group
      mailing list, and participants of the time zone mailing list.

The iCalendar date-time format is restricted to exactly one
representation of date-time (not optional spaces, dashes, ...).
There was a large debate on this before rfc2445 came out.
We decided on ONE format for date time based on ISO-8601

	YYYYMMDDTHHMMSS [+/- ...]

If the intent is to be human readable - both loose.
If the intent is to be machine readable - why another similar format?

-Doug

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From: Doug Royer <[email-masked]>
Date: Fri, 09 Nov 2001 16:38:59 -0700

Joe Abley wrote:
>  ....

No - not at all.

This is a BIG issue - if you want to understand it, go
to the calsch archives. Or send email to the [email-masked]
mailing list.

-Doug