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RE: Draft for review: Working with Time Zones

From: Phillips, Addison <addison@lab126.com>
Date: Sun, 20 Feb 2011 19:34:15 -0500
To: CE Whitehead <cewcathar@hotmail.com>
CC: "www-international@w3.org" <www-international@w3.org>
Message-ID: <C7A5719F1E562149BA9171F58BEE2CA412CBA78211@EX-IAD6-B.ant.amazon.com>
I have replied to the non-editorial comments below. Editorial comments I will consider separately.


Addison Phillips
Globalization Architect (Lab126)
Chair (W3C I18N, IETF IRI WGs)

Internationalization is not a feature.
It is an architecture.

How many time zones are in Russia?  It is not on the list of countries with more than one time zone (maybe there is something I do not understand).

AP> It is listed in the list of countries with multiple time zones. You quote the relevant paragraph in your message and it's listed there.

* * * COMMENTS * * *
What About Daylight Saving (Summer) Time: UTC Offset  (2nd par 1rst bullet)

"In addition, some time zones fall outside a single 24-hour span. "

{ How do they?  I'm a bit confused.  No need to clarify this but I guessed that
you meant for example that if we went from Greenwich back to Greenwich there could be more than 24 hours traversed -- because of daylight saving time or something? I guess I would like an example. }

AP> Time zones run from the international date line around to the international date line. And some time zones at or near the international date line observe daylight savings time. In addition, one country has a time zone whose UTC offset is -14:00. So the span of all time zones in the world exceeds a single 24-hour span.

* * *

[ NOT IMPORTANT? Floating Time, last par

{ COMMENT:  This may be a stupid question, but I did not understand the following: I think the day should only go to GMT-12:00?  For a twenty-four hour clock I mean. }
"That "day" can begin as early as midnight GMT-14:00 and end as late as midnight of January 2 GMT+12:00, depending on local time. This covers an incremental time range of fifty hours. "

AP> You might think that the day should only go to GMT-12:00, but as pointed about above, this isn't the case. In fact, it is called out here on purpose because it isn't "logical" that time zones should cover more than that. However, some time zones just west of the international date line do observe DST. And a few time zones that would normally fall east of the international date line have chosen to be west of it with an unusual offset. This helps some of the island nations of the Pacific all be on the same day at the same time, for example.

 * *
Identifying Zone from Offset and Country, par 1

" Only twenty countries have more than one observed time zone. These countries are:
Argentina, Australia, Brazil, Canada, Chile, Democratic Republic of the Congo, Ecuador, France, Greenland, Indonesia, Kazakhstan, Kiribati, Mexico, Micronesia, Mongolia, New Zealand, Portugal, Russia, Spain, and the United States. "

{ COMMENT ON CONTENT:  I don't see Russia; am I mistaken and does it only have one time zone or is there an omission?
I pulled up Russian time quickly in Wikipedia: http://en.wikipedia.org/wiki/Time_in_Russia }

AP> Russia is listed between Portugal and Spain in the list. See your own quote above.

* * *
Identifying Zone from Offset and Country, last par

"Within each of the countries that observe multiple time zones, knowing the current offset and current time will usually allow you to determine the time zone accurately. An exception to this is the United States: there exist some regions, such as Arizona, whose time zone cannot be determined strictly from country and offset, although an inferred time zone will always work for current time applications (not future and past times). "

{ COMMENT: regarding clarity, the comment about Arizona is confusing -- I assume you are talking about the fact that it does not go on daylight time in the summers and thus it's time is one hour behind the rest of the Mountain Time Zone in the summer; that's all I can think that you mean.  The rest of the year its time works fine. }

AP> That's what is meant. And actually time works fine year around in Arizona. However, knowing the offset and current time doesn't tell you whether you are in Arizona or in a neighboring region that *does* observe DST or not. Note that there are other examples besides Arizona. I will add additional information to the example to make this clear.
Received on Monday, 21 February 2011 00:34:49 UTC

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