draft-ietf-geopriv-pdif-lo-profile-09.txt   draft-ietf-geopriv-pdif-lo-profile-10.txt 
Geopriv J. Winterbottom Geopriv J. Winterbottom
Internet-Draft M. Thomson Internet-Draft M. Thomson
Updates: 4119 (if approved) Andrew Corporation Updates: 4119 (if approved) Andrew Corporation
Intended status: Standards Track H. Tschofenig Intended status: Standards Track H. Tschofenig
Expires: April 3, 2008 Nokia Siemens Networks Expires: April 12, 2008 Nokia Siemens Networks
October 1, 2007 October 10, 2007
GEOPRIV PIDF-LO Usage Clarification, Considerations and Recommendations GEOPRIV PIDF-LO Usage Clarification, Considerations and Recommendations
draft-ietf-geopriv-pdif-lo-profile-09.txt draft-ietf-geopriv-pdif-lo-profile-10.txt
Status of this Memo Status of this Memo
By submitting this Internet-Draft, each author represents that any By submitting this Internet-Draft, each author represents that any
applicable patent or other IPR claims of which he or she is aware applicable patent or other IPR claims of which he or she is aware
have been or will be disclosed, and any of which he or she becomes have been or will be disclosed, and any of which he or she becomes
aware will be disclosed, in accordance with Section 6 of BCP 79. aware will be disclosed, in accordance with Section 6 of BCP 79.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that Task Force (IETF), its areas, and its working groups. Note that
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and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
The list of current Internet-Drafts can be accessed at The list of current Internet-Drafts can be accessed at
http://www.ietf.org/ietf/1id-abstracts.txt. http://www.ietf.org/ietf/1id-abstracts.txt.
The list of Internet-Draft Shadow Directories can be accessed at The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html. http://www.ietf.org/shadow.html.
This Internet-Draft will expire on April 3, 2008. This Internet-Draft will expire on April 12, 2008.
Copyright Notice Copyright Notice
Copyright (C) The IETF Trust (2007). Copyright (C) The IETF Trust (2007).
Abstract Abstract
The Presence Information Data Format Location Object (PIDF-LO) The Presence Information Data Format Location Object (PIDF-LO)
specification provides a flexible and versatile means to represent specification provides a flexible and versatile means to represent
location information. There are, however, circumstances that arise location information. There are, however, circumstances that arise
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5
3. Using Location Information . . . . . . . . . . . . . . . . . . 6 3. Using Location Information . . . . . . . . . . . . . . . . . . 6
3.1. Single Civic Location Information . . . . . . . . . . . . 9 3.1. Single Civic Location Information . . . . . . . . . . . . 9
3.2. Civic and Geospatial Location Information . . . . . . . . 9 3.2. Civic and Geospatial Location Information . . . . . . . . 9
3.3. Manual/Automatic Configuration of Location Information . . 10 3.3. Manual/Automatic Configuration of Location Information . . 10
3.4. Multiple Location Objects in a Single PIDF-LO . . . . . . 11 3.4. Multiple Location Objects in a Single PIDF-LO . . . . . . 11
4. Geodetic Coordinate Representation . . . . . . . . . . . . . . 12 4. Geodetic Coordinate Representation . . . . . . . . . . . . . . 13
5. Geodetic Shape Representation . . . . . . . . . . . . . . . . 13 5. Geodetic Shape Representation . . . . . . . . . . . . . . . . 14
5.1. Polygon Restrictions . . . . . . . . . . . . . . . . . . . 14 5.1. Polygon Restrictions . . . . . . . . . . . . . . . . . . . 15
5.2. Shape Examples . . . . . . . . . . . . . . . . . . . . . . 15 5.2. Shape Examples . . . . . . . . . . . . . . . . . . . . . . 16
5.2.1. Point . . . . . . . . . . . . . . . . . . . . . . . . 15 5.2.1. Point . . . . . . . . . . . . . . . . . . . . . . . . 16
5.2.2. Polygon . . . . . . . . . . . . . . . . . . . . . . . 16 5.2.2. Polygon . . . . . . . . . . . . . . . . . . . . . . . 17
5.2.3. Circle . . . . . . . . . . . . . . . . . . . . . . . . 18 5.2.3. Circle . . . . . . . . . . . . . . . . . . . . . . . . 19
5.2.4. Ellipse . . . . . . . . . . . . . . . . . . . . . . . 19 5.2.4. Ellipse . . . . . . . . . . . . . . . . . . . . . . . 20
5.2.5. Arc Band . . . . . . . . . . . . . . . . . . . . . . . 21 5.2.5. Arc Band . . . . . . . . . . . . . . . . . . . . . . . 21
5.2.6. Sphere . . . . . . . . . . . . . . . . . . . . . . . . 22 5.2.6. Sphere . . . . . . . . . . . . . . . . . . . . . . . . 23
5.2.7. Ellipsoid . . . . . . . . . . . . . . . . . . . . . . 23 5.2.7. Ellipsoid . . . . . . . . . . . . . . . . . . . . . . 24
5.2.8. Prism . . . . . . . . . . . . . . . . . . . . . . . . 25 5.2.8. Prism . . . . . . . . . . . . . . . . . . . . . . . . 26
6. Security Considerations . . . . . . . . . . . . . . . . . . . 28 6. Security Considerations . . . . . . . . . . . . . . . . . . . 28
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 29 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 29
8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 30 8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 30
9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 31 9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 31
9.1. Normative references . . . . . . . . . . . . . . . . . . . 31 9.1. Normative references . . . . . . . . . . . . . . . . . . . 31
9.2. Informative References . . . . . . . . . . . . . . . . . . 31 9.2. Informative References . . . . . . . . . . . . . . . . . . 31
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 32 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 32
Intellectual Property and Copyright Statements . . . . . . . . . . 33 Intellectual Property and Copyright Statements . . . . . . . . . . 33
1. Introduction 1. Introduction
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nodes if sent over the network. nodes if sent over the network.
3.2. Civic and Geospatial Location Information 3.2. Civic and Geospatial Location Information
Mike is visiting his Seattle office and connects his laptop into the Mike is visiting his Seattle office and connects his laptop into the
Ethernet port in a spare cube. In this case location information is Ethernet port in a spare cube. In this case location information is
geodetic location, with the altitude represented as a building floor geodetic location, with the altitude represented as a building floor
number. Mike's main location is the point specified by the geodetic number. Mike's main location is the point specified by the geodetic
coordinates. Further, Mike is on the second floor of the building coordinates. Further, Mike is on the second floor of the building
located at these coordinates. Applying rules #6 and #7, the located at these coordinates. Applying rules #6 and #7, the
resulting compound location information is shown below. resulting compound location information is shown in Figure 2.
<?xml version="1.0" encoding="UTF-8"?> <?xml version="1.0" encoding="UTF-8"?>
<presence xmlns="urn:ietf:params:xml:ns:pidf" <presence xmlns="urn:ietf:params:xml:ns:pidf"
xmlns:dm="urn:ietf:params:xml:ns:pidf:data-model" xmlns:dm="urn:ietf:params:xml:ns:pidf:data-model"
xmlns:gp="urn:ietf:params:xml:ns:pidf:geopriv10" xmlns:gp="urn:ietf:params:xml:ns:pidf:geopriv10"
xmlns:cl="urn:ietf:params:xml:ns:pidf:geopriv10:civicAddr"
xmlns:gml="http://www.opengis.net/gml" xmlns:gml="http://www.opengis.net/gml"
xmlns:cl="urn:ietf:params:xml:ns:pidf:geopriv10:civicAddr"
entity="pres:mike@seattle.example.com"> entity="pres:mike@seattle.example.com">
<device id="sg89ab"> <dm:device id="mikepc">
<status> <status>
<gp:geopriv> <gp:geopriv>
<gp:location-info> <gp:location-info>
<gml:Point srsName="urn:ogc:def:crs:EPSG::4326" <gml:Point srsName="urn:ogc:def:crs:EPSG::4326">
<gml:pos>-43.5723 153.21760</gml:pos> <gml:pos>-43.5723 153.21760</gml:pos>
</gml:Point> </gml:Point>
<cl:civicAddress> <cl:civicAddress>
<cl:FLR>2</cl:FLR> <cl:FLR>2</cl:FLR>
</cl:civicAddress> </cl:civicAddress>
</gp:location-info> </gp:location-info>
<gp:usage-rules/> <gp:usage-rules/>
</gp:geopriv> </gp:geopriv>
</status> </status>
<timestamp>2003-06-22T20:57:29Z</timestamp> <timestamp>2007-06-22T20:57:29Z</timestamp>
<dm:deviceID>mac:8asd7d7d70</dm:deviceID> <dm:deviceID>mac:8asd7d7d70cf</dm:deviceID>
</device> </dm:device>
</presence> </presence>
Figure 2
3.3. Manual/Automatic Configuration of Location Information 3.3. Manual/Automatic Configuration of Location Information
Loraine has a predefined civic location stored in her laptop, since Loraine has a predefined civic location stored in her laptop, since
she normally lives in Sydney, the address is for her Sydney-based she normally lives in Sydney, the address is for her Sydney-based
apartment. Loraine decides to visit sunny San Francisco, and when apartment. Loraine decides to visit sunny San Francisco, and when
she gets there she plugs in her laptop and makes a call. Loraine's she gets there she plugs in her laptop and makes a call. Loraine's
laptop receives a new location from the visited network in San laptop receives a new location from the visited network in San
Francisco. As this system cannot be sure that the pre-existing, and Francisco. As this system cannot be sure that the pre-existing, and
new location, both describe the same place, Loraine's computer new location, both describe the same place, Loraine's computer
generates a new PIDF-LO and will use this to represent Loraine's generates a new PIDF-LO and will use this to represent Loraine's
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information may still be interpreted by the Location Recipient information may still be interpreted by the Location Recipient
providing Loraine's system applies rule #9. In this case the providing Loraine's system applies rule #9. In this case the
resulting order of location information in the PIDF document should resulting order of location information in the PIDF document should
be San Francisco first, followed by Sydney. Since the information is be San Francisco first, followed by Sydney. Since the information is
provided by different sources, rule #8 should also be applied and the provided by different sources, rule #8 should also be applied and the
information placed in different tuples with the tuple containing the information placed in different tuples with the tuple containing the
San Francisco location first. San Francisco location first.
3.4. Multiple Location Objects in a Single PIDF-LO 3.4. Multiple Location Objects in a Single PIDF-LO
Vanessa has her PC with her at the park, but to avoid being disturbed Vanessa has her PC with her at the park, but due to a
she reports her location as being in the office. The resulting misconfiguration, her PC reports her location as being in the office.
PIDF-LO will have a <device> element showing the location of The resulting PIDF-LO will have a <device> element showing the
Vanessa's PC as the park, and a <person> element saying that Vanessa location of Vanessa's PC as the park, and a <person> element saying
is in her office. that Vanessa is in her office.
<?xml version="1.0" encoding="UTF-8"?> <?xml version="1.0" encoding="UTF-8"?>
<presence xmlns="urn:ietf:params:xml:ns:pidf" <presence xmlns="urn:ietf:params:xml:ns:pidf"
xmlns:dm="urn:ietf:params:xml:ns:pidf:data-model" xmlns:dm="urn:ietf:params:xml:ns:pidf:data-model"
xmlns:gp="urn:ietf:params:xml:ns:pidf:geopriv10" xmlns:gp="urn:ietf:params:xml:ns:pidf:geopriv10"
xmlns:cl="urn:ietf:params:xml:ns:pidf:geopriv10:civicAddr" xmlns:cl="urn:ietf:params:xml:ns:pidf:geopriv10:civicAddr"
xmlns:gml="http://www.opengis.net/gml" xmlns:gml="http://www.opengis.net/gml"
entity="pres:mike@seattle.example.com"> xmlns:gs="http://www.opengis.net/pidflo/1.0"
<device id="nesspc-1"> entity="pres:ness@example.com">
<dm:device id="nesspc-1">
<status> <status>
<gp:geopriv> <gp:geopriv>
<gp:location-info> <gp:location-info>
<gml:Point srsName="urn:ogc:def:crs:EPSG::4326" <civicAddress xml:lang="en-AU">
<gml:pos>-43.5723 153.21760</gml:pos> <country>AU</country>
</gml:Point> <A1>NSW</A1>
<cl:civicAddress> <A3> Wollongong
<cl:FLR>2</cl:FLR> </A3><A4>North Wollongong
</cl:civicAddress> </A4>
<RD>Flinders</RD><STS>Street</STS>
<RDBR>Campbell Street</RDBR>
<LMK>
Gilligan's Island
</LMK> <LOC>Corner</LOC>
<NAM> Video Rental Store </NAM>
<PC>2500</PC>
<ROOM> Westerns and Classics </ROOM>
<PLC>store</PLC>
<POBOX>Private Box 15</POBOX>
</civicAddress>
</gp:location-info> </gp:location-info>
<gp:usage-rules/> <gp:usage-rules/>
</gp:geopriv> </gp:geopriv>
</status> </status>
<timestamp>2003-06-22T20:57:29Z</timestamp> <timestamp>2007-06-22T20:57:29Z</timestamp>
<dm:deviceID>mac:8asd7d7d70</dm:deviceID> <dm:deviceID>mac:1234567890ab</dm:deviceID>
</device> </dm:device>
<dm:person id="ness">
<status>
<gp:geopriv>
<gp:location-info>
<gs:Circle srsName="urn:ogc:def:crs:EPSG::4326">
<gml:pos>-34.410649 150.87651</gml:pos>
<gml:radius uom="urn:ogc:def:uom:EPSG::9001">
30
</gml:radius>
</gs:Circle>
</gp:location-info>
<gp:usage-rules/>
</gp:geopriv>
</status>
<timestamp>2007-06-24T12:28:04Z</timestamp>
</dm:person>
</presence> </presence>
Figure 3
4. Geodetic Coordinate Representation 4. Geodetic Coordinate Representation
The geodetic examples provided in RFC 4119 [RFC4119] are illustrated The geodetic examples provided in RFC 4119 [RFC4119] are illustrated
using the <gml:location> element, which uses the <gml:coordinates> using the <gml:location> element, which uses the <gml:coordinates>
element inside the <gml:Point> element and this representation has element inside the <gml:Point> element and this representation has
several drawbacks. Firstly, it has been deprecated in later versions several drawbacks. Firstly, it has been deprecated in later versions
of GML (3.1 and beyond) making it inadvisable to use for new of GML (3.1 and beyond) making it inadvisable to use for new
applications. Secondly, the format of the coordinates type is opaque applications. Secondly, the format of the coordinates type is opaque
and so can be difficult to parse and interpret to ensure consistent and so can be difficult to parse and interpret to ensure consistent
results, as the same geodetic location can be expressed in a variety results, as the same geodetic location can be expressed in a variety
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identified by the URN urn:ogc:def:uom:EPSG::9101 identified by the URN urn:ogc:def:uom:EPSG::9101
Implementations MUST specify the CRS using the srsName attribute on Implementations MUST specify the CRS using the srsName attribute on
the outermost geometry element. The CRS MUST NOT be respecified or the outermost geometry element. The CRS MUST NOT be respecified or
changed for any sub-elements. The srsDimension attribute SHOULD be changed for any sub-elements. The srsDimension attribute SHOULD be
omitted, since the number of dimensions in these CRSs is known. A omitted, since the number of dimensions in these CRSs is known. A
CRS MUST be specified using the above URN notation only; CRS MUST be specified using the above URN notation only;
implementations do not need to support user-defined CRSs. implementations do not need to support user-defined CRSs.
It is RECOMMENDED that where uncertainty is included, a confidence of It is RECOMMENDED that where uncertainty is included, a confidence of
68% (or one standard deviation) is used. Specifying a convention for 95% is used. Specifying a convention for confidence enables better
confidence enables better use of uncertainty values. use of uncertainty values.
5.1. Polygon Restrictions 5.1. Polygon Restrictions
The Polygon shape type defined in [GeoShape] intentionally does not The Polygon shape type defined in [GeoShape] intentionally does not
place any constraints on the number of vertices that may be included place any constraints on the number of vertices that may be included
to define the bounds of a polygon. This allows arbitrarily complex to define the bounds of a polygon. This allows arbitrarily complex
shapes to be defined and conveyed in a PIDF-LO. However, where shapes to be defined and conveyed in a PIDF-LO. However, where
location information is to be used in real-time processing location information is to be used in real-time processing
applications, such as location dependent routing, having arbitrarily applications, such as location dependent routing, having arbitrarily
complex shapes consisting of tens or even hundreds of points could complex shapes consisting of tens or even hundreds of points could
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shapes are used, how they are determined, and how they are shapes are used, how they are determined, and how they are
represented in a PIDF-LO. Complete details on all of the GeoShape represented in a PIDF-LO. Complete details on all of the GeoShape
types are provided in [GeoShape]. types are provided in [GeoShape].
5.2.1. Point 5.2.1. Point
The point shape type is the simplest form of geodetic LI, which is The point shape type is the simplest form of geodetic LI, which is
natively supported by GML. The gml:Point element is used when there natively supported by GML. The gml:Point element is used when there
is no known uncertainty. A point also forms part of a number of is no known uncertainty. A point also forms part of a number of
other geometries. A point may be specified using either WGS 84 other geometries. A point may be specified using either WGS 84
(latitude, longitude) or WGS 84 (latitude, longitude, altitude). The (latitude, longitude) or WGS 84 (latitude, longitude, altitude).
next example shows a 2d point: Figure 4 shows a 2d point:
<?xml version="1.0" encoding="UTF-8"?> <?xml version="1.0" encoding="UTF-8"?>
<presence xmlns="urn:ietf:params:xml:ns:pidf" <presence xmlns="urn:ietf:params:xml:ns:pidf"
xmlns:dm="urn:ietf:params:xml:ns:pidf:data-model"
xmlns:gp="urn:ietf:params:xml:ns:pidf:geopriv10" xmlns:gp="urn:ietf:params:xml:ns:pidf:geopriv10"
xmlns:cl="urn:ietf:params:xml:ns:pidf:geopriv10:civicAddr" xmlns:cl="urn:ietf:params:xml:ns:pidf:geopriv10:civicAddr"
xmlns:gs="http://www.opengis.net/pidflo/1.0"
xmlns:gml="http://www.opengis.net/gml" xmlns:gml="http://www.opengis.net/gml"
entity="pres:point2d@example.com"> entity="pres:point2d@example.com">
<device id="sg89abcd"> <dm:device id="point2d">
<status> <status>
<gp:geopriv> <gp:geopriv>
<gp:location-info> <gp:location-info>
<gml:Point srsName="urn:ogc:def:crs:EPSG::4326" <gml:Point srsName="urn:ogc:def:crs:EPSG::4326">
xmlns:gml="http://www.opengis.net/gml">
<gml:pos>-34.407 150.883</gml:pos> <gml:pos>-34.407 150.883</gml:pos>
</gml:Point> </gml:Point>
</gp:location-info> </gp:location-info>
<gp:usage-rules/> <gp:usage-rules/>
</gp:geopriv> </gp:geopriv>
</status> </status>
<timestamp>2007-06-22T20:57:29Z</timestamp> <timestamp>2007-06-22T20:57:29Z</timestamp>
</device> <dm:deviceID>mac:1234567890ab</dm:deviceID>
</dm:device>
</presence> </presence>
The next example shows a 3d point: Figure 4
Figure 5 shows a 3d point:
<?xml version="1.0" encoding="UTF-8"?> <?xml version="1.0" encoding="UTF-8"?>
<presence xmlns="urn:ietf:params:xml:ns:pidf" <presence xmlns="urn:ietf:params:xml:ns:pidf"
xmlns:dm="urn:ietf:params:xml:ns:pidf:data-model"
xmlns:gp="urn:ietf:params:xml:ns:pidf:geopriv10" xmlns:gp="urn:ietf:params:xml:ns:pidf:geopriv10"
xmlns:cl="urn:ietf:params:xml:ns:pidf:geopriv10:civicAddr"
xmlns:gs="http://www.opengis.net/pidflo/1.0"
xmlns:gml="http://www.opengis.net/gml" xmlns:gml="http://www.opengis.net/gml"
entity="pres:point3d@example.com"> entity="pres:point3d@example.com">
<device id="sg89ab5"> <dm:device id="point3d">
<status> <status>
<gp:geopriv> <gp:geopriv>
<gp:location-info> <gp:location-info>
<gml:Point srsName="urn:ogc:def:crs:EPSG::4979" <gml:Point srsName="urn:ogc:def:crs:EPSG::4979"
xmlns:gml="http://www.opengis.net/gml"> xmlns:gml="http://www.opengis.net/gml">
<gml:pos>-34.407 150.883 24.8</gml:pos> <gml:pos>-34.407 150.883 24.8</gml:pos>
</gml:Point> </gml:Point>
</gp:location-info> </gp:location-info>
<gp:usage-rules/> <gp:usage-rules/>
</gp:geopriv> </gp:geopriv>
</status> </status>
<timestamp>2007-06-22T20:57:29Z</timestamp> <timestamp>2007-06-22T20:57:29Z</timestamp>
</device> <dm:deviceID>mac:1234567890ab</dm:deviceID>
</dm:device>
</presence> </presence>
Figure 5
5.2.2. Polygon 5.2.2. Polygon
The polygon shape may be used to represent a building outline or The polygon shape may be used to represent a building outline or
coverage area. The first and last points of the polygon have to be coverage area. The first and last points of the polygon have to be
the same. For example, looking at the hexagon below with vertices, the same. For example, looking at the hexagon in Figure 6 with
A, F, E, D, C, B, A. The resulting polygon will be defined with 7 vertices, A, B, C, D, E, and F. The resulting polygon will be defined
points, with the first and last points both having the coordinates of with 7 points, with the first and last points both having the
point A. coordinates of point A.
B-------------C F--------------E
/ \ / \
/ \ / \
/ \ / \
A D A D
\ / \ /
\ / \ /
\ / \ /
F--------------E B--------------C
Figure 6
<?xml version="1.0" encoding="UTF-8"?> <?xml version="1.0" encoding="UTF-8"?>
<presence xmlns="urn:ietf:params:xml:ns:pidf" <presence xmlns="urn:ietf:params:xml:ns:pidf"
xmlns:gp="urn:ietf:params:xml:ns:pidf:geopriv10" xmlns:gp="urn:ietf:params:xml:ns:pidf:geopriv10"
xmlns:cl="urn:ietf:params:xml:ns:pidf:geopriv10:civicAddr"
xmlns:gs="http://www.opengis.net/pidflo/1.0"
xmlns:gml="http://www.opengis.net/gml" xmlns:gml="http://www.opengis.net/gml"
entity="pres:octagon@example.com"> entity="pres:hexagon@example.com">
<tuple id="sg89ab"> <tuple id="polygon-pos">
<status> <status>
<gp:geopriv> <gp:geopriv>
<gp:location-info> <gp:location-info>
<gml:Polygon srsName="urn:ogc:def:crs:EPSG::4326"> <gml:Polygon srsName="urn:ogc:def:crs:EPSG::4326">
<gml:exterior> <gml:exterior>
<gml:LinearRing> <gml:LinearRing>
<gml:pos>43.311 -73.422</gml:pos> <!--A--> <gml:pos>43.311 -73.422</gml:pos> <!--A-->
<gml:pos>43.111 -73.322</gml:pos> <!--F--> <gml:pos>43.111 -73.322</gml:pos> <!--B-->
<gml:pos>43.111 -73.222</gml:pos> <!--E--> <gml:pos>43.111 -73.222</gml:pos> <!--C-->
<gml:pos>43.311 -73.122</gml:pos> <!--D--> <gml:pos>43.311 -73.122</gml:pos> <!--D-->
<gml:pos>43.411 -73.222</gml:pos> <!--C--> <gml:pos>43.411 -73.222</gml:pos> <!--E-->
<gml:pos>43.411 -73.322</gml:pos> <!--B--> <gml:pos>43.411 -73.322</gml:pos> <!--F-->
<gml:pos>43.311 -73.422</gml:pos> <!--A--> <gml:pos>43.311 -73.422</gml:pos> <!--A-->
</gml:LinearRing> </gml:LinearRing>
</gml:exterior> </gml:exterior>
</gml:Polygon> </gml:Polygon>
</gp:location-info> </gp:location-info>
<gp:usage-rules/> <gp:usage-rules/>
</gp:geopriv> </gp:geopriv>
</status> </status>
<timestamp>2007-06-22T20:57:29Z</timestamp> <timestamp>2007-06-22T20:57:29Z</timestamp>
</tuple> </tuple>
skipping to change at page 18, line 8 skipping to change at page 19, line 8
Figure 7 Figure 7
In addition to the form shown in Figure 7 GML supports a posList In addition to the form shown in Figure 7 GML supports a posList
which provides a more compact representation for the coordinates of which provides a more compact representation for the coordinates of
the Polygon vertices than the discrete pos elements. The more the Polygon vertices than the discrete pos elements. The more
compact form is shown in Figure 8. Both forms are permitted. compact form is shown in Figure 8. Both forms are permitted.
<?xml version="1.0" encoding="UTF-8"?> <?xml version="1.0" encoding="UTF-8"?>
<presence xmlns="urn:ietf:params:xml:ns:pidf" <presence xmlns="urn:ietf:params:xml:ns:pidf"
xmlns:gp="urn:ietf:params:xml:ns:pidf:geopriv10" xmlns:gp="urn:ietf:params:xml:ns:pidf:geopriv10"
xmlns:cl="urn:ietf:params:xml:ns:pidf:geopriv10:civicAddr"
xmlns:gs="http://www.opengis.net/pidflo/1.0"
xmlns:gml="http://www.opengis.net/gml" xmlns:gml="http://www.opengis.net/gml"
entity="pres:octagon@example.com"> entity="pres:hexagon@example.com">
<tuple id="sg89ab"> <tuple id="polygon-poslist">
<status> <status>
<gp:geopriv> <gp:geopriv>
<gp:location-info> <gp:location-info>
<gml:Polygon srsName="urn:ogc:def:crs:EPSG::4326"> <gml:Polygon srsName="urn:ogc:def:crs:EPSG::4326">
<gml:exterior> <gml:exterior>
<gml:LinearRing> <gml:LinearRing>
<gml:posList>43.311 -73.422 43.111 -73.322 <gml:posList>
43.311 -73.422 43.111 -73.322
43.111 -73.222 43.311 -73.122 43.111 -73.222 43.311 -73.122
43.411 -73.222 43.411 -73.322 43.411 -73.222 43.411 -73.322
43.311 -73.422 43.311 -73.422
</gml:posList> </gml:posList>
</gml:LinearRing> </gml:LinearRing>
</gml:exterior> </gml:exterior>
</gml:Polygon> </gml:Polygon>
</gp:location-info> </gp:location-info>
<gp:usage-rules/> <gp:usage-rules/>
</gp:geopriv> </gp:geopriv>
skipping to change at page 19, line 8 skipping to change at page 20, line 8
one-dimensional geometry in GML, gml:CircleByCenterPoint. The centre one-dimensional geometry in GML, gml:CircleByCenterPoint. The centre
point of a circular area is specified by using a two dimensional CRS; point of a circular area is specified by using a two dimensional CRS;
in three dimensions, the orientation of the circle cannot be in three dimensions, the orientation of the circle cannot be
specified correctly using this representation. A point with specified correctly using this representation. A point with
uncertainty that is specified in three dimensions should use the uncertainty that is specified in three dimensions should use the
Sphere shape type. Sphere shape type.
<?xml version="1.0" encoding="UTF-8"?> <?xml version="1.0" encoding="UTF-8"?>
<presence xmlns="urn:ietf:params:xml:ns:pidf" <presence xmlns="urn:ietf:params:xml:ns:pidf"
xmlns:gp="urn:ietf:params:xml:ns:pidf:geopriv10" xmlns:gp="urn:ietf:params:xml:ns:pidf:geopriv10"
xmlns:cl="urn:ietf:params:xml:ns:pidf:geopriv10:civicAddr"
xmlns:gs="http://www.opengis.net/pidflo/1.0"
xmlns:gml="http://www.opengis.net/gml" xmlns:gml="http://www.opengis.net/gml"
xmlns:gs="http://www.opengis.net/pidflo/1.0"
entity="pres:circle@example.com"> entity="pres:circle@example.com">
<tuple id="sg89ab1"> <tuple id="circle">
<status> <status>
<gp:geopriv> <gp:geopriv>
<gp:location-info> <gp:location-info>
<gs:Circle srsName="urn:ogc:def:crs:EPSG::4326"> <gs:Circle srsName="urn:ogc:def:crs:EPSG::4326">
<gml:pos> <gml:pos>42.5463 -73.2512</gml:pos>
42.5463 -73.2512
</gml:pos>
<gml:radius uom="urn:ogc:def:uom:EPSG::9001"> <gml:radius uom="urn:ogc:def:uom:EPSG::9001">
850.24 850.24
</gml:radius> </gml:radius>
</gs:Circle> </gs:Circle>
</gp:location-info> </gp:location-info>
<gp:usage-rules/>
</gp:geopriv> </gp:geopriv>
</status> </status>
</tuple> </tuple>
</presence> </presence>
Figure 9
5.2.4. Ellipse 5.2.4. Ellipse
An elliptical area describes an ellipse in two dimensional space. An elliptical area describes an ellipse in two dimensional space.
The ellipse is described by a center point, the length of its semi- The ellipse is described by a center point, the length of its semi-
major and semi-minor axes, and the orientation of the semi-major major and semi-minor axes, and the orientation of the semi-major
axis. Like the circular area (Circle), the ellipse MUST be specified axis. Like the circular area (Circle), the ellipse MUST be specified
using the two dimensional CRS. using the two dimensional CRS.
<?xml version="1.0" encoding="UTF-8"?> <?xml version="1.0" encoding="UTF-8"?>
<presence xmlns="urn:ietf:params:xml:ns:pidf" <presence xmlns="urn:ietf:params:xml:ns:pidf"
xmlns:gp="urn:ietf:params:xml:ns:pidf:geopriv10" xmlns:gp="urn:ietf:params:xml:ns:pidf:geopriv10"
xmlns:cl="urn:ietf:params:xml:ns:pidf:geopriv10:civicAddr"
xmlns:gs="http://www.opengis.net/pidflo/1.0"
xmlns:gml="http://www.opengis.net/gml" xmlns:gml="http://www.opengis.net/gml"
xmlns:gs="http://www.opengis.net/pidflo/1.0"
entity="pres:Ellipse@somecell.example.com"> entity="pres:Ellipse@somecell.example.com">
<tuple id="sg89ab7"> <tuple id="ellipse">
<status> <status>
<gp:geopriv> <gp:geopriv>
<gp:location-info> <gp:location-info>
<gs:Ellipse srsName="urn:ogc:def:crs:EPSG::4326"> <gs:Ellipse srsName="urn:ogc:def:crs:EPSG::4326">
<gml:pos> <gml:pos>42.5463 -73.2512</gml:pos>
42.5463 -73.2512
</gml:pos>
<gs:semiMajorAxis uom="urn:ogc:def:uom:EPSG::9001"> <gs:semiMajorAxis uom="urn:ogc:def:uom:EPSG::9001">
1275 1275
</gs:semiMajorAxis> </gs:semiMajorAxis>
<gs:semiMinorAxis uom="urn:ogc:def:uom:EPSG::9001"> <gs:semiMinorAxis uom="urn:ogc:def:uom:EPSG::9001">
670 670
</gs:semiMinorAxis> </gs:semiMinorAxis>
<gs:orientation uom="urn:ogc:def:uom:EPSG::9102"> <gs:orientation uom="urn:ogc:def:uom:EPSG::9102">
43.2 43.2
</gs:orientation> </gs:orientation>
</gs:Ellipse> </gs:Ellipse>
</gp:location-info> </gp:location-info>
<gp:usage-rules/> <gp:usage-rules/>
</gp:geopriv> </gp:geopriv>
</status> </status>
<timestamp>2003-06-22T20:57:29Z</timestamp> <timestamp>2007-06-22T20:57:29Z</timestamp>
</tuple> </tuple>
</presence> </presence>
Figure 10
The gml:pos element indicates the position of the center, or origin, The gml:pos element indicates the position of the center, or origin,
of the ellipse. The gs:semiMajorAxis and gs:semiMinorAxis elements of the ellipse. The gs:semiMajorAxis and gs:semiMinorAxis elements
are the length of the semi-major and semi-minor axes respectively. are the length of the semi-major and semi-minor axes respectively.
The gs:orientation element is the angle by which the semi-major axis The gs:orientation element is the angle by which the semi-major axis
is rotated from the first axis of the CRS towards the second axis. is rotated from the first axis of the CRS towards the second axis.
For WGS 84, the orientation indicates rotation from Northing to For WGS 84, the orientation indicates rotation from Northing to
Easting, which, if specified in degrees, is roughly equivalent to a Easting, which, if specified in degrees, is roughly equivalent to a
compass bearing (if magnetic north were the same as the WGS north compass bearing (if magnetic north were the same as the WGS north
pole). Note: An ellipse with equal major and minor axis lengths is a pole). Note: An ellipse with equal major and minor axis lengths is a
circle. circle.
skipping to change at page 21, line 23 skipping to change at page 22, line 17
the location of the cell tower, the two radii are determined by the the location of the cell tower, the two radii are determined by the
extent of the timing advance, and the two angles are generally extent of the timing advance, and the two angles are generally
provisioned information. provisioned information.
For example, Paul is using a cellular wireless device and is 7 timing For example, Paul is using a cellular wireless device and is 7 timing
advance symbols away from the cell tower. For a GSM-based network advance symbols away from the cell tower. For a GSM-based network
this would place Paul roughly between 3,594 meters and 4,148 meters this would place Paul roughly between 3,594 meters and 4,148 meters
from the cell tower, providing the inner and outer radius values. If from the cell tower, providing the inner and outer radius values. If
the start angle is 20 degrees from north, and the opening angle is the start angle is 20 degrees from north, and the opening angle is
120 degrees, an arc band representing Paul's location would look 120 degrees, an arc band representing Paul's location would look
similar to the figure below. similar to Figure 11.
N ^ ,.__ N ^ ,.__
| a(s) / `-. | a(s) / `-.
| 20 / `-. | 20 / `-.
|--. / `. |--. / `.
| `/ \ | `/ \
| /__ \ | /__ \
| . `-. \ | . `-. \
| . `. \ | . `. \
|. \ \ . |. \ \ .
skipping to change at page 21, line 46 skipping to change at page 22, line 40
| . / ' | . / '
| . / ; | . / ;
.,' / .,' /
r(i)`. / r(i)`. /
(3594m) `. / (3594m) `. /
`. ,' `. ,'
`. ,' `. ,'
r(o)`' r(o)`'
(4148m) (4148m)
The resulting PIDF-LO is reflected below. Figure 11
The resulting PIDF-LO is shown in Figure 12.
<?xml version="1.0" encoding="UTF-8"?> <?xml version="1.0" encoding="UTF-8"?>
<presence xmlns="urn:ietf:params:xml:ns:pidf" <presence xmlns="urn:ietf:params:xml:ns:pidf"
xmlns:gp="urn:ietf:params:xml:ns:pidf:geopriv10" xmlns:gp="urn:ietf:params:xml:ns:pidf:geopriv10"
xmlns:cl="urn:ietf:params:xml:ns:pidf:geopriv10:civicAddr"
xmlns:gs="http://www.opengis.net/pidflo/1.0"
xmlns:gml="http://www.opengis.net/gml" xmlns:gml="http://www.opengis.net/gml"
xmlns:gs="http://www.opengis.net/pidflo/1.0"
entity="pres:paul@somecell.example.com"> entity="pres:paul@somecell.example.com">
<tuple id="sg89ab"> <tuple id="arcband">
<status> <status>
<gp:geopriv> <gp:geopriv>
<gp:location-info> <gp:location-info>
<gs:ArcBand srsName="urn:ogc:def:crs:EPSG::4326"> <gs:ArcBand srsName="urn:ogc:def:crs:EPSG::4326">
<gml:pos> <gml:pos>-43.5723 153.21760</gml:pos>
-43.5723 153.21760
</gml:pos>
<gs:innerRadius uom="urn:ogc:def:uom:EPSG::9001"> <gs:innerRadius uom="urn:ogc:def:uom:EPSG::9001">
3594 3594
</gs:innerRadius> </gs:innerRadius>
<gs:outerRadius uom="urn:ogc:def:uom:EPSG::9001"> <gs:outerRadius uom="urn:ogc:def:uom:EPSG::9001">
4148 4148
</gs:outerRadius> </gs:outerRadius>
<gs:startAngle uom="urn:ogc:def:uom:EPSG::9102"> <gs:startAngle uom="urn:ogc:def:uom:EPSG::9102">
20 20
</gs:startAngle> </gs:startAngle>
<gs:openingAngle uom="urn:ogc:def:uom:EPSG::9102"> <gs:openingAngle uom="urn:ogc:def:uom:EPSG::9102">
20 20
</gs:openingAngle> </gs:openingAngle>
</gs:ArcBand> </gs:ArcBand>
</gp:location-info> </gp:location-info>
<gp:usage-rules/> <gp:usage-rules/>
</gp:geopriv> </gp:geopriv>
</status> </status>
<timestamp>2003-06-22T20:57:29Z</timestamp> <timestamp>2007-06-22T20:57:29Z</timestamp>
</tuple> </tuple>
</presence> </presence>
Figure 12
An important note to make on the arc band is that the center point An important note to make on the arc band is that the center point
used in the definition of the shape is not included in resulting used in the definition of the shape is not included in resulting
enclosed area, and that Target may be anywhere in the defined area of enclosed area, and that Target may be anywhere in the defined area of
the arc band. the arc band.
5.2.6. Sphere 5.2.6. Sphere
The sphere is a volume that provides the same information as a circle The sphere is a volume that provides the same information as a circle
in three dimensions. The sphere has to be specified using a three in three dimensions. The sphere has to be specified using a three
dimensional CRS. The following example shows a sphere shape, which dimensional CRS. Figure 13 shows the sphere shape, which is
is identical to the circle example, except for the addition of an identical to the circle example, except for the addition of an
altitude in the provided coordinates. altitude in the provided coordinates.
<?xml version="1.0" encoding="UTF-8"?> <?xml version="1.0" encoding="UTF-8"?>
<presence xmlns="urn:ietf:params:xml:ns:pidf" <presence xmlns="urn:ietf:params:xml:ns:pidf"
xmlns:gp="urn:ietf:params:xml:ns:pidf:geopriv10" xmlns:gp="urn:ietf:params:xml:ns:pidf:geopriv10"
xmlns:cl="urn:ietf:params:xml:ns:pidf:geopriv10:civicAddr"
xmlns:gs="http://www.opengis.net/pidflo/1.0"
xmlns:gml="http://www.opengis.net/gml" xmlns:gml="http://www.opengis.net/gml"
xmlns:gs="http://www.opengis.net/pidflo/1.0"
entity="pres:circle@example.com"> entity="pres:circle@example.com">
<tuple id="sg89ab1"> <tuple id="sphere">
<status> <status>
<gp:geopriv> <gp:geopriv>
<gp:location-info> <gp:location-info>
<gs:Sphere srsName="urn:ogc:def:crs:EPSG::4979"> <gs:Sphere srsName="urn:ogc:def:crs:EPSG::4979">
<gml:pos> <gml:pos>42.5463 -73.2512 26.3</gml:pos>
42.5463 -73.2512 26.3
</gml:pos>
<gs:radius uom="urn:ogc:def:uom:EPSG::9001"> <gs:radius uom="urn:ogc:def:uom:EPSG::9001">
850.24 850.24
</gs:radius> </gs:radius>
</gs:Sphere> </gs:Sphere>
</gp:location-info> </gp:location-info>
<gp:usage-rules/>
</gp:geopriv> </gp:geopriv>
</status> </status>
</tuple> </tuple>
</presence> </presence>
Figure 13
5.2.7. Ellipsoid 5.2.7. Ellipsoid
The ellipsoid is the volume most commonly produced by GPS systems. The ellipsoid is the volume most commonly produced by GPS systems.
It is used extensively in navigation systems and wireless location It is used extensively in navigation systems and wireless location
networks. The ellipsoid is constructed around a central point networks. The ellipsoid is constructed around a central point
specified in three dimensions, and three axies perpendicular to one specified in three dimensions, and three axies perpendicular to one
another are extended outwards from this point. These axies are another are extended outwards from this point. These axies are
defined as the semi-major (M) axis, the semi-minor (m) axis, and the defined as the semi-major (M) axis, the semi-minor (m) axis, and the
vertical (v) axis respectively. An angle is used to express the vertical (v) axis respectively. An angle is used to express the
orientation of the ellipsoid. The orientation angle is measured in orientation of the ellipsoid. The orientation angle is measured in
skipping to change at page 24, line 16 skipping to change at page 25, line 16
_.-\""""^"""""-._ _.-\""""^"""""-._
.' \ | `. .' \ | `.
/ v m \ / v m \
| \ | | | \ | |
| -c ----M---->| | -c ----M---->|
| | | |
\ / \ /
`._ _.' `._ _.'
`-...........-' `-...........-'
A PIDF-LO containing an ellipsoid would like something like the Figure 14
sample below.
A PIDF-LO containing an ellipsoid appears as shown in Figure 15.
<?xml version="1.0" encoding="UTF-8"?> <?xml version="1.0" encoding="UTF-8"?>
<presence xmlns="urn:ietf:params:xml:ns:pidf" <presence xmlns="urn:ietf:params:xml:ns:pidf"
xmlns:gp="urn:ietf:params:xml:ns:pidf:geopriv10" xmlns:gp="urn:ietf:params:xml:ns:pidf:geopriv10"
xmlns:cl="urn:ietf:params:xml:ns:pidf:geopriv10:civicAddr"
xmlns:gs="http://www.opengis.net/pidflo/1.0"
xmlns:gml="http://www.opengis.net/gml" xmlns:gml="http://www.opengis.net/gml"
xmlns:gs="http://www.opengis.net/pidflo/1.0"
entity="pres:somone@gpsreceiver.example.com"> entity="pres:somone@gpsreceiver.example.com">
<tuple id="sg89ab"> <tuple id="ellipsoid">
<status> <status>
<gp:geopriv> <gp:geopriv>
<gp:location-info> <gp:location-info>
<gs:Ellipsoid srsName="urn:ogc:def:crs:EPSG::4979"> <gs:Ellipsoid srsName="urn:ogc:def:crs:EPSG::4979">
<gml:pos> <gml:pos>42.5463 -73.2512 26.3</gml:pos>
42.5463 -73.2512 26.3
</gml:pos>
<gs:semiMajorAxis uom="urn:ogc:def:uom:EPSG::9001"> <gs:semiMajorAxis uom="urn:ogc:def:uom:EPSG::9001">
7.7156 7.7156
</gs:semiMajorAxis> </gs:semiMajorAxis>
<gs:semiMinorAxis uom="urn:ogc:def:uom:EPSG::9001"> <gs:semiMinorAxis uom="urn:ogc:def:uom:EPSG::9001">
3.31 3.31
</gs:semiMinorAxis> </gs:semiMinorAxis>
<gs:verticalAxis uom="urn:ogc:def:uom:EPSG::9001"> <gs:verticalAxis uom="urn:ogc:def:uom:EPSG::9001">
28.7 28.7
</gs:verticalAxis> </gs:verticalAxis>
<gs:orientation uom="urn:ogc:def:uom:EPSG::9102"> <gs:orientation uom="urn:ogc:def:uom:EPSG::9102">
90 90
</gs:orientation> </gs:orientation>
</gs:Ellipsoid> </gs:Ellipsoid>
</gp:location-info> </gp:location-info>
<gp:usage-rules/> <gp:usage-rules/>
</gp:geopriv> </gp:geopriv>
</status> </status>
<timestamp>2003-06-22T20:57:29Z</timestamp> <timestamp>2007-06-22T20:57:29Z</timestamp>
</tuple> </tuple>
</presence> </presence>
Figure 15
5.2.8. Prism 5.2.8. Prism
A prism may be used to represent a section of a building or range of A prism may be used to represent a section of a building or range of
floors of building. The prism extrudes a polygon by providing a floors of building. The prism extrudes a polygon by providing a
height element. It consists of a base made up of coplanar points height element. It consists of a base made up of coplanar points
defined in 3 dimensions all at the same altitude. The prism is then defined in 3 dimensions all at the same altitude. The prism is then
an extrusion from this base to the value specified in the height an extrusion from this base to the value specified in the height
element. If the height is negative, then the prism is extruded from element. If the height is negative, then the prism is extruded from
the top down, while a positive height extrudes from the bottom up. the top down, while a positive height extrudes from the bottom up.
The first and last points of the polygon have to be the same. The first and last points of the polygon have to be the same.
For example, looking at the cube below. If the prism is extruded For example, looking at the cube in Figure 16. If the prism is
from the bottom up, then the polygon forming the base of the prism is extruded from the bottom up, then the polygon forming the base of the
defined with the points A, B, C, D, A. The height of the prism is the prism is defined with the points A, B, C, D, A. The height of the
distance between point A and point E in meters. The resulting prism is the distance between point A and point E in meters.
PIDF-LO is provided below.
G-----F G-----F
/| /| /| /|
/ | / | / | / |
H--+--E | H--+--E |
| C--|--B | C--|--B
| / | / | / | /
|/ |/ |/ |/
D-----A D-----A
Figure 16
The resulting PIDF-LO is shown in Figure 17.
<?xml version="1.0" encoding="UTF-8"?> <?xml version="1.0" encoding="UTF-8"?>
<presence xmlns="urn:ietf:params:xml:ns:pidf" <presence xmlns="urn:ietf:params:xml:ns:pidf"
xmlns:gp="urn:ietf:params:xml:ns:pidf:geopriv10" xmlns:gp="urn:ietf:params:xml:ns:pidf:geopriv10"
xmlns:cl="urn:ietf:params:xml:ns:pidf:geopriv10:civicAddr"
xmlns:gs="http://www.opengis.net/pidflo/1.0"
xmlns:gml="http://www.opengis.net/gml" xmlns:gml="http://www.opengis.net/gml"
xmlns:gs="http://www.opengis.net/pidflo/1.0"
entity="pres:mike@someprism.example.com"> entity="pres:mike@someprism.example.com">
<tuple id="sg89ab"> <tuple id="prism">
<status> <status>
<gp:geopriv> <gp:geopriv>
<gp:location-info> <gp:location-info>
<gs:Prism srsName="urn:ogc:def:crs:EPSG::4979"> <gs:Prism srsName="urn:ogc:def:crs:EPSG::4979">
<gs:base> <gs:base>
<gml:Polygon> <gml:Polygon>
<gml:exterior> <gml:exterior>
<gml:LinearRing> <gml:LinearRing>
<gml:posList> <gml:posList>
42.556844 -73.248157 36.6 <!--A--> 42.556844 -73.248157 36.6 <!--A-->
skipping to change at page 28, line 5 skipping to change at page 27, line 43
</gs:height> </gs:height>
</gs:Prism> </gs:Prism>
</gp:location-info> </gp:location-info>
<gp:usage-rules/> <gp:usage-rules/>
</gp:geopriv> </gp:geopriv>
</status> </status>
<timestamp>2007-06-22T20:57:29Z</timestamp> <timestamp>2007-06-22T20:57:29Z</timestamp>
</tuple> </tuple>
</presence> </presence>
Figure 17
6. Security Considerations 6. Security Considerations
The primary security considerations relate to how location The primary security considerations relate to how location
information is conveyed and used, which are outside the scope of this information is conveyed and used, which are outside the scope of this
document. This document is intended to serve only as a set of document. This document is intended to serve only as a set of
guidelines as to which elements MUST or SHOULD be implemented by guidelines as to which elements MUST or SHOULD be implemented by
systems wishing to perform location dependent routing. The systems wishing to perform location dependent routing. The
ramification of such recommendations is that they extend to devices ramification of such recommendations is that they extend to devices
and clients that wish to make use of such services. and clients that wish to make use of such services.
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