Re: [tz] Theory - proposal to delete the reference to population
On Sun, May 13, 2012 at 1:46 AM, Paul Eggert <eggert@cs.ucla.edu> wrote:
On 05/12/2012 04:08 AM, Tobias Conradi wrote:
If two ships enter territorial waters of HM
They'll continue to do what they've always done, which is keep their own times at the discretion of their captains. Do you have any source, international treaty or so, to support your claim?
If they get on land, would that change your claim, or would they observe what has been reported as official time for HM by Australian agencies? -- Tobias Conradi Rheinsberger Str. 18 10115 Berlin Germany http://tobiasconradi.com/
I cannot give a treaty or anything, but a lot of my work is for shipping, and I can confirm that ships may maintain whatever time the captain wants. For example, on cross-channel ferries between Dover and Calais where the trip takes much less than an hour, they do not adjust ship's time by an hour every time they go between UK (GMT) and French (+1) times. Tim Smartcom Software Ltd Portsmouth Technopole Kingston Crescent Portsmouth PO2 8FA United Kingdom www.smartcomsoftware.com Smartcom Software is a limited company registered in England and Wales, registered number 05641521. -----Original Message----- From: tz-bounces@iana.org [mailto:tz-bounces@iana.org] On Behalf Of Tobias Conradi Sent: 18 May 2012 17:03 To: tz@iana.org Subject: Re: [tz] Theory - proposal to delete the reference to population On Sun, May 13, 2012 at 1:46 AM, Paul Eggert <eggert@cs.ucla.edu> wrote:
On 05/12/2012 04:08 AM, Tobias Conradi wrote:
If two ships enter territorial waters of HM
They'll continue to do what they've always done, which is keep their own times at the discretion of their captains. Do you have any source, international treaty or so, to support your claim?
If they get on land, would that change your claim, or would they observe what has been reported as official time for HM by Australian agencies? -- Tobias Conradi Rheinsberger Str. 18 10115 Berlin Germany http://tobiasconradi.com/
On Fri, May 18, 2012 at 6:28 PM, Tim Thornton <tt@smartcomsoftware.com> wrote:
I cannot give a treaty or anything, but a lot of my work is for shipping, and I can confirm that ships may maintain whatever time the captain wants. For example, on cross-channel ferries between Dover and Calais where the trip takes much less than an hour, they do not adjust ship's time by an hour every time they go between UK (GMT) and French (+1) times.
Does this apply to communication with the respective ports, and between ships? -- Tobias Conradi Rheinsberger Str. 18 10115 Berlin Germany http://tobiasconradi.com/
http://home.tiscali.nl/~t876506/Multizones.html says "As soon as the territorial waters of a nation is reached, the clock is set to the local time of that (part of the) nation." -- Tobias Conradi Rheinsberger Str. 18 10115 Berlin Germany http://tobiasconradi.com/
" The information on this page is by no means authoritative. " Dafydd Rhys-Jones | Platform Test Engineer F5 Networks www.f5.com Our Kung fu is Stronger P 206.272. 5555 D 206.272.6280 F 206.272.5556 M 206.291.0706 -----Original Message----- From: tz-bounces@iana.org [mailto:tz-bounces@iana.org] On Behalf Of Tobias Conradi Sent: Friday, May 18, 2012 11:21 AM To: tz@iana.org Subject: Re: [tz] Theory - proposal to delete the reference to population http://home.tiscali.nl/~t876506/Multizones.html says "As soon as the territorial waters of a nation is reached, the clock is set to the local time of that (part of the) nation." -- Tobias Conradi Rheinsberger Str. 18 10115 Berlin Germany http://tobiasconradi.com/
On Fri, May 18, 2012 at 8:26 PM, Dafydd Rhys-Jones <D.Rhys-Jones@f5.com> wrote:
" The information on this page is by no means authoritative. " This doesn't change the statement.
Not authoritative too is: ftp://ftp.iana.org/tz/data too. Authoritative is a government website as far as government rules are involved. -- Tobias Conradi Rheinsberger Str. 18 10115 Berlin Germany http://tobiasconradi.com/
Correct, and I see no entry in maritime law that requires time zone changes underway. Have you found one? Thanks, Dafydd Dafydd Rhys-Jones | Platform Test Engineer F5 Networks www.f5.com Our Kung fu is Stronger P 206.272. 5555 D 206.272.6280 F 206.272.5556 M 206.291.0706 -----Original Message----- From: tz-bounces@iana.org [mailto:tz-bounces@iana.org] On Behalf Of Tobias Conradi Sent: Friday, May 18, 2012 11:30 AM To: tz@iana.org Subject: Re: [tz] Theory - proposal to delete the reference to population On Fri, May 18, 2012 at 8:26 PM, Dafydd Rhys-Jones <D.Rhys-Jones@f5.com> wrote:
" The information on this page is by no means authoritative. " This doesn't change the statement.
Not authoritative too is: ftp://ftp.iana.org/tz/data too. Authoritative is a government website as far as government rules are involved. -- Tobias Conradi Rheinsberger Str. 18 10115 Berlin Germany http://tobiasconradi.com/
That said, while serving in the US Navy, we honored Time Zone changes while underway, so it may very well be dependent on the shipping organization. D Dafydd Rhys-Jones | Platform Test Engineer F5 Networks www.f5.com Our Kung fu is Stronger P 206.272. 5555 D 206.272.6280 F 206.272.5556 M 206.291.0706 -----Original Message----- From: tz-bounces@iana.org [mailto:tz-bounces@iana.org] On Behalf Of Tobias Conradi Sent: Friday, May 18, 2012 11:30 AM To: tz@iana.org Subject: Re: [tz] Theory - proposal to delete the reference to population On Fri, May 18, 2012 at 8:26 PM, Dafydd Rhys-Jones <D.Rhys-Jones@f5.com> wrote:
" The information on this page is by no means authoritative. " This doesn't change the statement.
Not authoritative too is: ftp://ftp.iana.org/tz/data too. Authoritative is a government website as far as government rules are involved. -- Tobias Conradi Rheinsberger Str. 18 10115 Berlin Germany http://tobiasconradi.com/
http://www.iana.org/time-zones/repository/tz-link.html says: "A ship within the territorial waters of any nation uses that nation's time." contradicts Paul Eggert "May 13, 2012 at 1:46 AM"
If two ships enter territorial waters of HM They'll continue to do what they've always done, which is keep their own times at the discretion of their captains.
-- Tobias Conradi Rheinsberger Str. 18 10115 Berlin Germany http://tobiasconradi.com/
Thanks for the very, very cool refs! Having been on a Newport to Bermuda racing sailboat, I can testify from firsthand experience that there isn't any enforcement backing regulations about how clocks must be set aboard ships at sea. Natural Timezones and Territorial Waters are cool as can be, but our race start was noted in America/New_York, the finish was recorded in Bermuda local time (UTC-4?), and all we really cared about was the interval, plus restaurant closing times after we arrived. Whether ship's time is constrained by anything other than the whim of the skipper is very dependent on circumstance. We didn't shift our watches mid-race to reflect the change.
International law says that any nation has the right to enfoce its own laws within its own territorial waters (12 nautical miles?), which implies that a nation COULD enforce timezone laws within its territorial waters. Many nations encourage it, but don't enforce it. For signatories of the UN Law of the Sea, which is almost everyone except the USA, nations can ENCOURAGE that that their laws be applied as far as 200 nautical miles. But whether any nations enforce timezone laws within territorial waters is up to each nation. But it is certainly common practice to use port time when docked at port. See also: http://en.wikipedia.org/wiki/Territorial_waters
On Fri, May 18, 2012 at 9:35 PM, David Patte <dpatte@relativedata.com> wrote:
International law says that any nation has the right to enfoce its own laws within its own territorial waters (12 nautical miles?), which implies that a nation COULD enforce timezone laws within its territorial waters. Many nations encourage it, but don't enforce it. How is time offset observation enforced? It is used by government agencies, but people are mostly free to do what they want. If several people use a single different offset than is specified in law, then the IANA time zone database records these.
For HM there is no report of such (systematic) deviation. In absence Australian laws/regulations would apply. But Paul Eggert does not want to incorporate them, giving as reason that this tract of land and surrounding water has not permanent population. Same for Bouvet Island, which belongs to the Kingdom of Norway and is located ~3° east of the Greenwich Meridian. -------- http://www.lovdata.no/all/hl-20070126-004.html § 6. Norsk normaltid Normaltiden i Norge er én time foran koordinert universaltid (UTC+1). -------- Removing the provision referring to population and creating zones for BV and HM would solve the above issues and also help people that want to have at least one zone per ISO 3166-1 alpha-2 code. -- Tobias Conradi Rheinsberger Str. 18 10115 Berlin Germany http://tobiasconradi.com/
How is time offset observation enforced?
The Time Zone Police, naturally. I think they're headquartered on Cape Cod. You know, having followed this thread intently for the last couple of days, I think we might be onto something. Clearly the tzinfo database needs to reflect the wall-clock time of every clock on the planet. Just glancing around my office, I count at least ten clocks, with offsets ranging from UTC+00:00:05 to UTC-05:02:10. Some of these clocks are on servers and use some approximation of UTC (it changes as the BIOS clocks lose or gain time over time), some are on laptops at UTC-05:something, and there's an antique clock permanently stuck at 7:03. (Or 19:03...I can't tell.) Of course, the servers and laptops occasionally reach out to NTP servers, so I'll have to capture exactly when they do this to make sure tzinfo maintains an accurate history. If someone would volunteer to go through all the system logs, we can probably piece together some of it, but unfortunately some of the logs have been overwritten. This logically requires substantial updates to the gazetteer. As I'm on the third floor of this building, we'll have to expand the locales/places/areas list to three dimensions. Oh--and my servers are stacked up five in a rack, so right there we've got five new time zones overlaying one square meter of Chicago. I almost forgot, I'm wearing a wristwatch, and I have a mobile phone, two digital cameras, and a handheld GPS receiver, all of which have (or are) clocks of some sort. We can ignore the GPS receiver, since GPS is pretty much the most accurate clock generally available. But still, I'm excited by the possibilities of creating a new zone for each of the mobile devices. Especially the wristwatches. We'll need to get everyone on the planet a notebook to write down when they adjust their watches, else the database just won't be complete. But how will we represent the watches/mobile phones/cameras moving through space? I'll be on an airplane tomorrow, traveling from the America/Chicago zone to America/Los_Angeles. I usually change my watch after takeoff. So we'll need to find some way to represent when that happens, because obviously that creates a new time zone right in seat 9F. I'll explain this to the flight attendants so all 150 of us can change at the same time, just to keep things simple. So look forward to an update tomorrow: + Rule Flight581 2012 only - May 19 14:25 -2:00 F + Zone America/Chicago/Flight581 -7:00 - PDT 2012 May 19 14:25 Ah, but wait, I'm over-reaching. The key is "wall clock time." That rules out every clock not attached to a wall. It turns out, none of my clocks is attached to a wall, so never mind. It's still a vexing problem, though: how do we represent a time zone with no clocks in it? Wow. We've got a lot of work to do. Let's to it, then. Or, in the alternative, we can just do our best to capture the general rules for approximate areas of the planet's surface that have both people and clocks, and call it "good enough."
I believe a navigator, sailing to an island, would like to know its recomended timezone, without having to prove it has any people currently living on the island first. On 2012-05-18 17:22, David Braverman wrote:
How is time offset observation enforced? The Time Zone Police, naturally. I think they're headquartered on Cape Cod.
You know, having followed this thread intently for the last couple of days, I think we might be onto something. Clearly the tzinfo database needs to reflect the wall-clock time of every clock on the planet.
Just glancing around my office, I count at least ten clocks, with offsets ranging from UTC+00:00:05 to UTC-05:02:10. Some of these clocks are on servers and use some approximation of UTC (it changes as the BIOS clocks lose or gain time over time), some are on laptops at UTC-05:something, and there's an antique clock permanently stuck at 7:03. (Or 19:03...I can't tell.) Of course, the servers and laptops occasionally reach out to NTP servers, so I'll have to capture exactly when they do this to make sure tzinfo maintains an accurate history. If someone would volunteer to go through all the system logs, we can probably piece together some of it, but unfortunately some of the logs have been overwritten.
This logically requires substantial updates to the gazetteer. As I'm on the third floor of this building, we'll have to expand the locales/places/areas list to three dimensions. Oh--and my servers are stacked up five in a rack, so right there we've got five new time zones overlaying one square meter of Chicago.
I almost forgot, I'm wearing a wristwatch, and I have a mobile phone, two digital cameras, and a handheld GPS receiver, all of which have (or are) clocks of some sort. We can ignore the GPS receiver, since GPS is pretty much the most accurate clock generally available. But still, I'm excited by the possibilities of creating a new zone for each of the mobile devices. Especially the wristwatches. We'll need to get everyone on the planet a notebook to write down when they adjust their watches, else the database just won't be complete.
But how will we represent the watches/mobile phones/cameras moving through space? I'll be on an airplane tomorrow, traveling from the America/Chicago zone to America/Los_Angeles. I usually change my watch after takeoff. So we'll need to find some way to represent when that happens, because obviously that creates a new time zone right in seat 9F. I'll explain this to the flight attendants so all 150 of us can change at the same time, just to keep things simple. So look forward to an update tomorrow:
+ Rule Flight581 2012 only - May 19 14:25 -2:00 F + Zone America/Chicago/Flight581 -7:00 - PDT 2012 May 19 14:25
Ah, but wait, I'm over-reaching. The key is "wall clock time." That rules out every clock not attached to a wall. It turns out, none of my clocks is attached to a wall, so never mind. It's still a vexing problem, though: how do we represent a time zone with no clocks in it?
Wow. We've got a lot of work to do. Let's to it, then.
Or, in the alternative, we can just do our best to capture the general rules for approximate areas of the planet's surface that have both people and clocks, and call it "good enough."
--
David Patte <dpatte@relativedata.com> writes:
I believe a navigator, sailing to an island, would like to know its recomended timezone, without having to prove it has any people currently living on the island first.
Why? Of what possible use is the "local time" of an uninhabited island? What, *specifically*, would the navigator use that time to do? Time zones are fundamentally about coordination with other people; for technical and scientific purposes, UTC and similar time standards serve just fine. Governments create enough work for database maintenance without pursuing undefined concepts in the name of an unrealistic sense of completeness. -- Russ Allbery (rra@stanford.edu) <http://www.eyrie.org/~eagle/>
On Sat, May 19, 2012 at 12:12 AM, Russ Allbery <rra@stanford.edu> wrote:
David Patte <dpatte@relativedata.com> writes:
I believe a navigator, sailing to an island, would like to know its recomended timezone, without having to prove it has any people currently living on the island first.
Why? Of what possible use is the "local time" of an uninhabited island? What, *specifically*, would the navigator use that time to do?
Time zones are fundamentally about coordination with other people;
Exactly. http://mm.icann.org/pipermail/tz/2012-May/017817.html May 12 Tobias Conradi asked: "If two ships enter territorial waters of HM would the Olson-Eggert-IANA time zone database give them advice for how to set their clocks?" -- Tobias Conradi Rheinsberger Str. 18 10115 Berlin Germany http://tobiasconradi.com/
On 05/18/2012 06:34 PM, Tobias Conradi wrote:
"If two ships enter territorial waters of HM would the Olson-Eggert-IANA time zone database give them advice for how to set their clocks?"
Set them exactly as if the islands were not there. Which is the correct answer: the rule that the Australian government imposes gives an identical result.
On Sat, May 19, 2012 at 1:24 AM, Kevin Kenny <kkenny2@nycap.rr.com> wrote:
On 05/18/2012 06:34 PM, Tobias Conradi wrote:
"If two ships enter territorial waters of HM would the Olson-Eggert-IANA time zone database give them advice for how to set their clocks?"
Set them exactly as if the islands were not there. But it is reported that they do exist.
Which is the correct answer: the rule that the Australian government imposes gives an identical result. It doesn't. It only may agree in offset from UTC and also that only as long as the Australian offset rule for HM doesn't change.
-- Tobias Conradi Rheinsberger Str. 18 10115 Berlin Germany http://tobiasconradi.com/
On 19/05/12 01:16, Tobias Conradi wrote:
On Sat, May 19, 2012 at 1:24 AM, Kevin Kenny<kkenny2@nycap.rr.com> wrote:
On 05/18/2012 06:34 PM, Tobias Conradi wrote:
"If two ships enter territorial waters of HM would the Olson-Eggert-IANA time zone database give them advice for how to set their clocks?"
Set them exactly as if the islands were not there. But it is reported that they do exist.
Which is the correct answer: the rule that the Australian government imposes gives an identical result. It doesn't. It only may agree in offset from UTC and also that only as long as the Australian offset rule for HM doesn't change.
So nothing needs to be done until then. -- -=( Ian Abbott @ MEV Ltd. E-mail: <abbotti@mev.co.uk> )=- -=( Tel: +44 (0)161 477 1898 FAX: +44 (0)161 718 3587 )=-
On Sat, May 19, 2012 at 9:07 AM, Ian Abbott <abbotti@mev.co.uk> wrote:
On 19/05/12 01:16, Tobias Conradi wrote:
On Sat, May 19, 2012 at 1:24 AM, Kevin Kenny<kkenny2@nycap.rr.com> wrote:
On 05/18/2012 06:34 PM, Tobias Conradi wrote:
"If two ships enter territorial waters of HM would the Olson-Eggert-IANA time zone database give them advice for how to set their clocks?"
Set them exactly as if the islands were not there.
But it is reported that they do exist.
Which is the correct answer: the rule that the Australian government imposes gives an identical result.
It doesn't.
So nothing needs to be done until then. Depends on the definition of need.
If no zone for HM is created the bug remains. -- Tobias Conradi Rheinsberger Str. 18 10115 Berlin Germany http://tobiasconradi.com/
Date: Sat, 19 May 2012 12:13:43 +0200 From: Tobias Conradi <tobias.conradi@gmail.com> Message-ID: <CAAGevbWdJf_Gr7cbZdYzhkrDbTQn7cZTdWkrKgOfZ-tz5=x=Mg@mail.gmail.com> | If no zone for HM is created the bug remains. Have you considered the possibility that the "bug" is in ISO3166, which has issued a country code for an object that meets no rational criteria for being a country? If they'd just delete HM (and BV), then there would be no argument at all for us to do anything, right? Please turn your attention to the people who set the contents of ISO3166, inform them of the problem they've caused by defining a country code (or two), and so, apparently, demanding that timezone data be created for an object(s) with no clocks, and so no time (or zones) and demand that they fix t. Report back here when you've finished that. kre
On Sat, May 19, 2012 at 1:39 PM, Robert Elz <kre@munnari.oz.au> wrote:
Date: Sat, 19 May 2012 12:13:43 +0200 From: Tobias Conradi <tobias.conradi@gmail.com> Message-ID: <CAAGevbWdJf_Gr7cbZdYzhkrDbTQn7cZTdWkrKgOfZ-tz5=x=Mg@mail.gmail.com>
| If no zone for HM is created the bug remains.
Have you considered the possibility that the "bug" is in ISO3166, No. Since Theory imports the ISO 3166-1 definition to define a country in the IANA time zone database.
which has issued a country code for an object that meets no rational criteria for being a country? That is your personal point of view.
If they'd just delete HM (and BV), then there would be no argument at all for us to do anything, right? If the territories currently covered by HM and BV is covered by any zone this would be correct. I don't see this to be true.
Please turn your attention to the people who set the contents of ISO3166, inform them of the problem they've caused by defining a country code (or two), and so, apparently, demanding that timezone data be created for an object(s) with no clocks, The objects have "clocks" if "clocks" means officially defined time and objects means the territories of HM and BV.
and so no time (or zones) and demand that they fix t.
Report back here when you've finished that. I do want I want to do. If you have slave like behavior and let other people command you, this is fine.
-- Tobias Conradi Rheinsberger Str. 18 10115 Berlin Germany http://tobiasconradi.com/
On Sat, May 19, 2012 at 3:06 PM, Tobias Conradi <tobias.conradi@gmail.com> wrote:
On Sat, May 19, 2012 at 1:39 PM, Robert Elz <kre@munnari.oz.au> wrote:
Date: Sat, 19 May 2012 12:13:43 +0200 From: Tobias Conradi <tobias.conradi@gmail.com> Message-ID: <CAAGevbWdJf_Gr7cbZdYzhkrDbTQn7cZTdWkrKgOfZ-tz5=x=Mg@mail.gmail.com>
| If no zone for HM is created the bug remains.
Have you considered the possibility that the "bug" is in ISO3166, No. Since Theory imports the ISO 3166-1 definition to define a country in the IANA time zone database.
which has issued a country code for an object that meets no rational criteria for being a country? That is your personal point of view.
If they'd just delete HM (and BV), then there would be no argument at all for us to do anything, right? If the territories currently covered by HM and BV is covered by any zone this would be correct. I don't see this to be true.
Please turn your attention to the people who set the contents of ISO3166, inform them of the problem they've caused by defining a country code (or two), and so, apparently, demanding that timezone data be created for an object(s) with no clocks, The objects have "clocks" if "clocks" means officially defined time and objects means the territories of HM and BV.
and so no time (or zones) and demand that they fix t.
Report back here when you've finished that. I do want I want to do. If you have slave like behavior and let other people command you, this is fine. typo:
I do want I want to do.-> I do what I want to do. -- Tobias Conradi Rheinsberger Str. 18 10115 Berlin Germany http://tobiasconradi.com/
Tobias Conradi <tobias.conradi@gmail.com> writes:
"If two ships enter territorial waters of HM would the Olson-Eggert-IANA time zone database give them advice for how to set their clocks?"
This is not a sufficiently specified scenario to be analyzable. Missing data includes why they're setting their clocks and what they're trying to coordinate with each other. Have you been captaining a ship entering those territorial waters and had a specific problem around time zones? If so, please do explain; that would be useful information to have in deciding what the database should do. If not, I would suggest that this is an artificial, invented problem that may never have occurred and may never become real, at which point the standard best practices of software development kick in. Adding prospective, theoretical database entries to solve problems that we don't fully understand and that have never been specified by someone who is attempting to solve that problem is a bad idea. Such code or data is almost guaranteed to be buggy and wrong when the situation actually arises, since the real world rarely behaves like our preliminary guesses. Of equal or greater importance as completeness is to decline to state a rule when there is no known rule to state. Artificial accuracy can cause as many problems as missing data. -- Russ Allbery (rra@stanford.edu) <http://www.eyrie.org/~eagle/>
On Sat, May 19, 2012 at 2:03 AM, Russ Allbery <rra@stanford.edu> wrote:
Tobias Conradi <tobias.conradi@gmail.com> writes:
"If two ships enter territorial waters of HM would the Olson-Eggert-IANA time zone database give them advice for how to set their clocks?"
This is not a sufficiently specified scenario to be analyzable. Maybe for you.
Have you been captaining a ship entering those territorial waters and had a specific problem around time zones? If so, please do explain; that would be useful information to have in deciding what the database should do.
If not, I would suggest that this is an artificial, invented problem That doesn't remove the bug.
-- Tobias Conradi Rheinsberger Str. 18 10115 Berlin Germany http://tobiasconradi.com/
I personally _have_ been captain of a ship crossing the Pacific Ocean several years ago. Shipboard clocks were always set to reflect local time when entering territorial waters. And, while we were in international waters, as captain I ordered clocks to be adjusted as we crossed each "natural" longitude-based tz border. Ship-board watches followed official ship's time as ordered by me. (If anyone actually cares, I do have a mini-blog of the trip on- line at http://www.sailblogs.com/member/gentle-wind/ )
-----Original Message----- From: tz-bounces@iana.org [mailto:tz-bounces@iana.org] On Behalf Of Russ Allbery Sent: Friday, May 18, 2012 5:04 PM To: tz@iana.org Subject: Re: [tz] Theory - proposal to delete the reference to population
Tobias Conradi <tobias.conradi@gmail.com> writes:
"If two ships enter territorial waters of HM would the Olson-Eggert- IANA time zone database give them advice for how to set their clocks?"
This is not a sufficiently specified scenario to be analyzable. Missing data includes why they're setting their clocks and what they're trying to coordinate with each other.
Have you been captaining a ship entering those territorial waters and had a specific problem around time zones? If so, please do explain; that would be useful information to have in deciding what the database should do.
If not, I would suggest that this is an artificial, invented problem that may never have occurred and may never become real, at which point the standard best practices of software development kick in. Adding prospective, theoretical database entries to solve problems that we don't fully understand and that have never been specified by someone who is attempting to solve that problem is a bad idea. Such code or data is almost guaranteed to be buggy and wrong when the situation actually arises, since the real world rarely behaves like our preliminary guesses.
Of equal or greater importance as completeness is to decline to state a rule when there is no known rule to state. Artificial accuracy can cause as many problems as missing data.
-- Russ Allbery (rra@stanford.edu) <http://www.eyrie.org/~eagle/>
Paul Goyette <pgoyette@juniper.net> wrote: |I personally _have_ been captain of a ship crossing the Pacific |Ocean several years ago. I've used the formal way to ask the German »Bundesmarine« to let a qualified specialist add the Navy point of view. Maybe they will answer. (On a working day.) --steffen Forza Figa!
Steffen Daode Nurpmeso <sdaoden@gmail.com> wrote: |Paul Goyette <pgoyette@juniper.net> wrote: | | |I personally _have_ been captain of a ship crossing the Pacific | |Ocean several years ago. | |I've used the formal way to ask the German »Bundesmarine« to let |a qualified specialist add the Navy point of view. |Maybe they will answer. (On a working day.) I've been redirected to a different department and sent the new request some minutes ago. Maybe They Answer. Thanks. --steffen Forza Figa!
Do we get a royalty every time someone instantiates a new clock? :)
-----Original Message----- From: tz-bounces@iana.org [mailto:tz-bounces@iana.org] On Behalf Of David Braverman Sent: Friday, May 18, 2012 2:23 PM To: tz@iana.org Subject: Re: [tz] Theory - proposal to delete the reference to population
How is time offset observation enforced?
The Time Zone Police, naturally. I think they're headquartered on Cape Cod.
You know, having followed this thread intently for the last couple of days, I think we might be onto something. Clearly the tzinfo database needs to reflect the wall-clock time of every clock on the planet.
Just glancing around my office, I count at least ten clocks, with offsets ranging from UTC+00:00:05 to UTC-05:02:10. Some of these clocks are on servers and use some approximation of UTC (it changes as the BIOS clocks lose or gain time over time), some are on laptops at UTC- 05:something, and there's an antique clock permanently stuck at 7:03. (Or 19:03...I can't tell.) Of course, the servers and laptops occasionally reach out to NTP servers, so I'll have to capture exactly when they do this to make sure tzinfo maintains an accurate history. If someone would volunteer to go through all the system logs, we can probably piece together some of it, but unfortunately some of the logs have been overwritten.
This logically requires substantial updates to the gazetteer. As I'm on the third floor of this building, we'll have to expand the locales/places/areas list to three dimensions. Oh--and my servers are stacked up five in a rack, so right there we've got five new time zones overlaying one square meter of Chicago.
I almost forgot, I'm wearing a wristwatch, and I have a mobile phone, two digital cameras, and a handheld GPS receiver, all of which have (or are) clocks of some sort. We can ignore the GPS receiver, since GPS is pretty much the most accurate clock generally available. But still, I'm excited by the possibilities of creating a new zone for each of the mobile devices. Especially the wristwatches. We'll need to get everyone on the planet a notebook to write down when they adjust their watches, else the database just won't be complete.
But how will we represent the watches/mobile phones/cameras moving through space? I'll be on an airplane tomorrow, traveling from the America/Chicago zone to America/Los_Angeles. I usually change my watch after takeoff. So we'll need to find some way to represent when that happens, because obviously that creates a new time zone right in seat 9F. I'll explain this to the flight attendants so all 150 of us can change at the same time, just to keep things simple. So look forward to an update tomorrow:
+ Rule Flight581 2012 only - May 19 14:25 -2:00 F + Zone America/Chicago/Flight581 -7:00 - PDT 2012 May 19 14:25
Ah, but wait, I'm over-reaching. The key is "wall clock time." That rules out every clock not attached to a wall. It turns out, none of my clocks is attached to a wall, so never mind. It's still a vexing problem, though: how do we represent a time zone with no clocks in it?
Wow. We've got a lot of work to do. Let's to it, then.
Or, in the alternative, we can just do our best to capture the general rules for approximate areas of the planet's surface that have both people and clocks, and call it "good enough."
On Fri 2012-05-18T19:45:41 +0200, Tobias Conradi hath writ:
Does this apply to communication with the respective ports, and between ships?
In international waters these are regulated by the ITU-R and IMO. In territorial waters those same regulations are usually incorporated by reference into national law along with additional sections on enforcement. Those are thousands of pages of documentation evolved for over a century, but I'm certain that tz already implements a superset of all such use. -- Steve Allen <sla@ucolick.org> WGS-84 (GPS) UCO/Lick Observatory--ISB Natural Sciences II, Room 165 Lat +36.99855 1156 High Street Voice: +1 831 459 3046 Lng -122.06015 Santa Cruz, CA 95064 http://www.ucolick.org/~sla/ Hgt +250 m
participants (13)
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Bennett Todd -
Dafydd Rhys-Jones -
David Braverman -
David Patte -
Ian Abbott -
Kevin Kenny -
Paul Goyette -
Robert Elz -
Russ Allbery -
Steffen Daode Nurpmeso -
Steve Allen -
Tim Thornton -
Tobias Conradi