Re: [Tzdist] Next step

Jonathan Lennox <lennox@cs.columbia.edu> Mon, 19 October 2015 15:05 UTC

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Date: Mon, 19 Oct 2015 11:05:03 -0400
From: Jonathan Lennox <lennox@cs.columbia.edu>
To: Cyrus Daboo <cyrus@daboo.name>
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Cc: tzdist@ietf.org, Ken Murchison <murch@andrew.cmu.edu>
Subject: Re: [Tzdist] Next step
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On Monday, October 19 2015, "Cyrus Daboo" wrote to "Ken Murchison, tzdist@ietf.org"; saying:

> Hi Ken,
> 
> --On October 19, 2015 at 10:14:28 AM -0400 Ken Murchison 
> <murch@andrew.cmu.edu>; wrote:
> 
> > Actually, would this be a mapping from something like "Pittsburgh, PA" ->
> > "America/New_York", or from GPS coordinates to a tzid, or both?
> 
> I would prefer just geo URI -> tzid, and leave address->geo to some other 
> service (since that is useful in a number of other situations - not just 
> tzdist).

It's a separate protocol, and might be more heaviweight than folks would
prefer, but I'd recommend looking at the Location-to-Service-Translation
protocol (LoST), RFC 5222.  It was originally engineered to let people find
the appropriate emergency call center (i.e. 911, 112, 999, etc.) for their
current location.  It's designed to work for both geo and civic addresses.

I'm inclined *not* to say that only geographic coordinates should be
handled, because usually, the semantic of TZIDs maps to civic location
(i.e. "In Tennessee, Roane County uses America/New_York, Cumberland County
uses America/Chicago"), and round-tripping this through geo location can
introduce error.

-- 
Jonathan Lennox
lennox@cs.columbia.edu