Subject: Re: Geographic location representations?

From: Andrew Daviel <[email-masked]>
Date: Sat, 07 Jul 2001 02:25:48 -0700 (PDT)

On Tue, 26 Jun 2001, Paul Knight wrote:

> Glad to see the WG chartered.
>
> I see the plan is that "the working group will select an already
> standardized format to recommend for use in representing location per se."
> I am working on an I-D which uses location information, and am very
> interested in the candidate formats.
>
> Is there a list of known formats?  pointers?

I wrote a somewhat reductionist draft which is mentioned in the charter,
viz.
http://geotags.com/geo/draft-daviel-html-geo-tag-05.html

This is intended for adding location data to legacy HTML documents using
META elements familiar to most Web authors. The number of elements and
options is deliberately small in order to minimize errors when coding by
hand. XML is probably an appropriate encapsulation for new applications.

Other formats I have come across include:
DublinCore (coverage) http://dublincore.org/documents/1998/09/dces
FGDC http://www.fgdc.gov/
ISO/TC211 http://www.statkart.no/isotc211/
NMEA 0183 http://vancouver-webpages.com/peter/nmeafaq.txt etc.
vCard RFC2445 http://www.alternic.org/rfcs/rfc2400/rfc2426.txt
RFC1876 http://www.alternic.org/rfcs/rfc1800/rfc1876.txt
ISO6709 ftp://ftp.informatik.uni-erlangen.de/pub/doc/ISO/ISO-6709-summary

Many of the available formats are created for specific purposes and
may not be suitable for this WG. For instance, NMEA is designed for
connecting marine autopilots to navigation sets such as GPS.
FGDC and other GIS data formats I believe are created to describe
objects such as maps or satellite images, typically rectangular
areas aligned North-South.

I suggest adopting WGS-84, because that is what the GPS system uses and
GPS chips are becoming ubiquitious. Converting between different datums
is a big headache in my opinion.
There are some issues concerning altitude using WGS-4 (altitude is not
intuitive, since the datum is not
"ground level", or "sea level" for coastal areas, but a geometric
construct) but it satisfies the requirement of a single universal
measurement grid for location-based devices.

-- 
Andrew Daviel
Vancouver Webpages

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From: Bobby Sardana <[email-masked]>
Date: Sat, 07 Jul 2001 10:28:50 -0700

Greetings:

I remember reading something on the lines of 'location' & HTML in one of the
OPES drafts (www.extproxy.org).

Regards,

Bobby Sardana.
[email-masked]

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From: Andrew Daviel <[email-masked]>
Date: Sun, 08 Jul 2001 17:00:40 -0700 (PDT)

> OPES drafts (www.extproxy.org).

http://search.ietf.org/internet-drafts/draft-maciocco-opes-omml-00.txt
4.4.2 "location" element

   The "location" element specifies the proxyletÆs fully qualified name
   where the domain name might be different from the "id" element. For
   example company A owns and develops the proxylet and so the "id"
   element will be <id>A.com</id> but company A makes this proxylet

Doesn't seem to be relevant. More like the HTTP Location header which
is used in a redirect

Andrew Daviel

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From: "James M. Polk" <[email-masked]>
Date: Fri, 13 Jul 2001 13:30:44 -0500

Andrew

I agree with using WGS84 here

>measurement grid for location-based devices.

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