Subject: Re: Geopriv WG - meeting 5-6 Jun, other news

From: Randall Gellens <[email-masked]>
Date: Tue, 21 May 2002 16:33:06 -0700

At 4:28 PM -0400 5/16/02, Richard Shockey wrote:

>   It strikes me there are two key requirements here which is 1. a 
> Location Object which is the semantic expression of location data 
> and other useful information ( raw or other ) of the Target that 
> can be interpreted by Location Seeker in order to act upon it and 
> 2. A Location Privacy Object that presumably under the control Rule 
> Maker ( perhaps the Target ) that expresses what information can be 
> transferred and under what conditions.  Both of these objects 
> reside in this "Location Server" that can be queried by some 
> undefined and presumably out of scope application mechanism keyed 
> on by some identifier ( phone number for instance).
>
>   I submit that any discussion of transport of geopriv objects be 
> deemed out of scope and those discussions are best left to the 
> applications that need geopriv data ...SIP for instance.

It may be worth keeping in mind some example usages.  For instance, 
there is an existing draft on requesting and disclosing location 
information within HTTP.  In that context, a web browser (perhaps on 
a cell phone) requests a document and is asked for its location. 
There is a wide range of possibilities in how it answers that 
request, depending in many ways on what we end up with here in 
geopriv.

For example, the web server could partially fill in some sort of 
geopriv object, to indicate the required precision and age, its 
identity, and perhaps some broad category of use.  If the web knows 
its location but doesn't have the power to process policy, it could 
perhaps fill in its location but encrypt it, and indicate a location 
server to which the web server can go to get the data decrypted 
subject to policy.

Such example uses raise questions about the information that needs to 
be in the object(s), if the policy itself is included or not, and if 
an identifier is included or not.  (In the HTTP example, there is no 
need for a geopriv target identifier.)

---

From: Eric Brunner-Williams in Portland Maine <[email-masked]>
Date: Tue, 21 May 2002 19:37:22 -0400

> information within HTTP.

Are you refering to the daviel drafts, either in -geo-tag- or -geo-header-
form?

---

From: Randall Gellens <[email-masked]>
Date: Tue, 21 May 2002 17:28:17 -0700

>  Are you refering to the daviel drafts, either in -geo-tag- or -geo-header-

Yes, I was referring to the header draft 
(<ftp://ftp.ietf.org/internet-drafts/draft-daviel-http-geo-header-04.txt>), 
and I apologize for not mentioning it my name before, but for my 
purposes here the specifics aren't important, only the intended use.

---

From: Eric Brunner-Williams in Portland Maine <[email-masked]>
Date: Tue, 21 May 2002 21:41:05 -0400

Well, since its -02 incantation it appears to have grown a syntax ("semantics")
section anyone familiar with e.164 syntax would appreciate, but not much else
of note.

2. Coordinate Systems
   ... WGS 84 ...

I've a preference for UTC96. Tastes vary.

3. Implementation
   ... "geo.region" is used for the country subdivision code from ISO 3166-2

Nope. Can't use iso3166.

7. Applicability
   ...
                   ... They may not be used to describe a non-localised,
   moving, or intangible object such as a multinational company, river,
   aircraft or mathematical theory.
               ^^^^^^^^^^^^^^^^^^^
I'm relieved by that last bit.

8. Security Considerations
   This draft raises no security issues.
   This draft raises no significant privacy issues ...

I don't agree.

9. Internationalization consideration
   ... should use US-ASCII or UTF-8.

Nope. Not with that either.

IANA considerations (none).

I looked at Andrew's work two years ago and didn't find it interesting.

>                                                   ... but for my 

Some I-Ds are used to float (temporarily) some marketing ploy or another.
Personally I think the specifics are the only thing important in any I-D.

Cheers,
Eric

---

From: [email-masked]
Date: Wed, 22 May 2002 10:03:17 -0600

Eric -

In terms of coordinate systems, I might refer you and the WG to work being
done in the LIF (Location Interoperability Forum) and the OGC. The OGC has,
through a member driven consensus process, defined a specification for the
expression of coordinate reference systems (CRS) that is applicable to both
tightly coupled and loosely coupled application implementations. LIF has
adopted the use of the OGC approach. The OGC work has been harmonized with
the ISO work related to CRS. You can access the OGC public documents on this
topic at www.opengis.org and then going to the approved specifications page.

Regards

Carl Reed
Exec. Dir. Specification Program
OGC

----- Original Message -----
From: "Eric Brunner-Williams in Portland Maine" <[email-masked]>
To: "Randall Gellens" <[email-masked]>
Cc: "Eric Brunner-Williams in Portland Maine" <[email-masked]>;
"Richard Shockey" <[email-masked]>;
<[email-masked]>; <[email-masked]>
Sent: Tuesday, May 21, 2002 7:41 PM
Subject: Re: Geopriv WG - meeting 5-6 Jun, other news

---

From: Eric Brunner-Williams in Portland Maine <[email-masked]>
Date: Wed, 22 May 2002 13:33:18 -0400

Carl,

Thanks for the pointer.

After 10 minutes mousing around I still don't know anything concret, other
than there are a lot of documents, and there is a pointer back to the SLP
BoF I proposed to Randy and Haitao held, back in November of '00. Kwel.

Could you be more specific? Assume I'm very dumb, and prone to get lost
when I'm not prone. Something one can put in the References section of a
draft.

Tia,
Eric

---

From: [email-masked]
Date: Wed, 22 May 2002 13:40:15 -0600

Eric -

Sorry about that!

There are several references.

The first is from the OGC Abstract Specification (AS). The AS provides the
abstract models as the foundation and reference for the OGC implementation
specifications. The URL for the topic volume on coordinate reference systems
(CRS) is:  http://www.opengis.org/techno/abstract/02-102.pdf . The web page
says that this is version 1. It is actually version 6. It has been vetted by
world known experts in geodesy and spatial reference systems. It is also
synchronized with ISO.

The second is an example of an implementation specification for a "tightly"
coupled implementation. The example used is Java. The URL is:
http://www.opengis.org/techno/implementation.htm

The third is how CRSs are referenced in the world of the Web and Web
Services. The OGC membership has agreed upon a common way to specify a CRS
(also known as an SRS) in OGC interface specifications. An excellent example
of this can be found in the OGC Web Map Server Specification, also found at
the URL: http://www.opengis.org/techno/implementation.htm . The parameter to
look for is SRS.

In all cases, the CRS model is consistent with the ISO TC 211 document. We
use something called the EPSG as the actual authority. However, we also
realize that application developers may wish to specify their own CRS
parameters and not reference the authority. This is also fine.

Hope this all helps!

Regards

Carl

----- Original Message -----
From: "Eric Brunner-Williams in Portland Maine" <[email-masked]>
To: <[email-masked]>
Cc: "Eric Brunner-Williams in Portland Maine" <[email-masked]>;
"Randall Gellens" <[email-masked]>; "Richard Shockey"
<[email-masked]>; <[email-masked]>;
<[email-masked]>
Sent: Wednesday, May 22, 2002 11:33 AM
Subject: Re: Geopriv WG - meeting 5-6 Jun, other news