From: Miguel Cruz on
Mxsmanic <mxsmanic(a)gmail.com> wrote:
> Miguel Cruz writes:
>> If you know where you are then you can synchronize with microsecond
>> accuracy against other devices that also know where they are, using
>> freely-available time-of-day sources.
>
> It's not that easy, because of propagation delays and variation
> therein.
>
>> Hint: Cell towers are not using NTP.
>
> Whatever they use, the principle is the same.

No, the only thing they have to worry about are delays and echoes
introduced by radio reflection.

>> No, because the point is to get the clocks at multiple locations
>> synchronized with each other.
>
> There aren't too many protocols that require that, and even of those
> that do, often propagation delay is ignored. The stations are
> synchronized after allowing for delays, but they aren't necessarily
> synchronized with an absolute time of day.

The easiest way to synchronize them is using a common time source.

> It's possible to synchronize with time of day with accuracies of tens
> of milliseconds without too much trouble, but below that threshold
> things get complicated and expensive. Even NTP is a complicated
> protocol, specifically because it is so hard to make it highly
> accurate.

NTP has to deal with problems that fixed-position radio receivers don't.
All of its problems and hurdles are irrelevant.

miguel
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From: Dave Frightens Me on
On 14 Aug 2006 18:18:12 -0700, "Tchiowa" <tchiowa2(a)hotmail.com> wrote:

>
>Miguel Cruz wrote:

>> Contrast this with Athens and Berlin. A tiny minority of the people have
>> shared fluency in any language.
>
>Almost all speak English.

*chuckle*

You would be one of those ignorant yanks if you believe this!

>> They share a handful of TV channels,
>> mostly the channels that are available in New York and New Orleans as
>> well. Popular music and films are different, the cuisines have less
>> overlap,
>
>You think New Orleans food is similar to what you get in NYC?

It's a hell of a lot closer than Greek salad and Sauerkraut.
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DFM - http://www.deepfriedmars.com
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From: Hatunen on
On Tue, 15 Aug 2006 10:34:10 +0100, The Reid
<dontuse(a)fell-walker.co.uk> wrote:

>Following up to Hatunen
>
>>>> Nonsense. The difference in culture between New York City, San
>>>> Francisco, Miami, New Orleans are every bit as great.
>>>
>>>No, they're not.
>>
>>In many ways they really are. For instance, if you spend any time
>>in Miami you will quickly realize it is a Caribbean city.
>
>are different parts of US more different than the Basques from
>the Galicians from the Catalans from the gypsies from the
>madrilanos?

I think the Mexicans here in southern Arizona are different from
your ordinary Phoenician, and certainly the Navajos are different
from anyone else in the USA. The naarby Pascua Yaqui are quite
different, from Kansans, and from Navajos and Mexicans, and from
their neighbs, the Tohono O'odham.

Yes I think we can claim quite a few different and distinct
cultures. We even have Basques in some areas.

************* DAVE HATUNEN (hatunen(a)cox.net) *************
* Tucson Arizona, out where the cacti grow *
* My typos & mispellings are intentional copyright traps *
From: Hatunen on
On Tue, 15 Aug 2006 09:51:11 -0400, Miguel Cruz <spam(a)admin.u.nu>
wrote:

>Mxsmanic <mxsmanic(a)gmail.com> wrote:
>> Miguel Cruz writes:
>>> If you know where you are then you can synchronize with microsecond
>>> accuracy against other devices that also know where they are, using
>>> freely-available time-of-day sources.
>>
>> It's not that easy, because of propagation delays and variation
>> therein.
>>
>>> Hint: Cell towers are not using NTP.
>>
>> Whatever they use, the principle is the same.
>
>No, the only thing they have to worry about are delays and echoes
>introduced by radio reflection.
>
>>> No, because the point is to get the clocks at multiple locations
>>> synchronized with each other.
>>
>> There aren't too many protocols that require that, and even of those
>> that do, often propagation delay is ignored. The stations are
>> synchronized after allowing for delays, but they aren't necessarily
>> synchronized with an absolute time of day.
>
>The easiest way to synchronize them is using a common time source.

But there will always be propagation time differences from that
source to the devices being synched.


************* DAVE HATUNEN (hatunen(a)cox.net) *************
* Tucson Arizona, out where the cacti grow *
* My typos & mispellings are intentional copyright traps *
From: Dave Frightens Me on
On 14 Aug 2006 18:09:13 -0700, "Tchiowa" <tchiowa2(a)hotmail.com> wrote:

>
>Jordi wrote:

>> No, they're not.
>
>Spoken like a true Euro who have never been to the US.
>
>Before you come up with the "smart" response, I've been to Europe
>probably 100 times and visited a large number of European countries.

Nice one. How come you have such an odd view of Europe? Is it because
you are lying?

>> There's history, you see. Are you by any chance pretending the US is
>> exempt from those?
>
>No. Just pointing out the fact that the reason so many Euros have
>passports is due to hatred and bigotry, not some cultural superiority
>as has been implied.

Very bizzare response.

>> > > No, we're talking two completely different things. All this came after
>> > > you said more or less 'what's the use of holidays if people don't have
>> > > money to spend', Europeans do have enough money to keep a... say
>> > > 'western' lifestyle without having to work 51 weeks a year, that's all.
>> >
>> > But their "western" lifestyle is lower than American's.
>>
>> In what sense? 1.0 litre less of engine?, 4 less inches on a flat TV?
>> Having some real vacation weighs substantially more on overal quality
>> of life.
>
>As do a lot of other things. Most Americans have "real" vacations and
>most have more to spend on their vacations that Euros do.

That is meaningless, as you included "real", which could mean
anything.

>> If you are talking on an international level, you will see many of
>> these allegedly burdened employers competing hand to hand with other
>> 'unburdened' ones.
>
>With a whole lot less employees which is demonstrated by the high
>unemployment rates in Europe.

You are talking about just which countries out of the forty or so?
--
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DFM - http://www.deepfriedmars.com
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