One document matched: draft-thomson-geopriv-held-capabilities-04.txt

Differences from draft-thomson-geopriv-held-capabilities-03.txt




GEOPRIV                                                       M. Thomson
Internet-Draft                                           J. Winterbottom
Intended status: Standards Track                                  Andrew
Expires: January 4, 2009                                    July 3, 2008


 Device Capability Negotiation for Device-Based Location Determination
                   and Location Measurements in HELD
               draft-thomson-geopriv-held-capabilities-04

Status of This Memo

   By submitting this Internet-Draft, each author represents that any
   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
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   This Internet-Draft will expire on January 4, 2009.

Abstract

   A framework for the exchange of capabilities in HELD is described.
   Capabilities for enabling device-based measurements and device-based
   location generation are described.











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Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
   2.  Conventions used in this document  . . . . . . . . . . . . . .  3
   3.  Capabilities Exchange Overview . . . . . . . . . . . . . . . .  3
     3.1.  Capabilities Exchange  . . . . . . . . . . . . . . . . . .  5
   4.  The Capability Indication  . . . . . . . . . . . . . . . . . .  6
     4.1.  Retrieving Data from the Device  . . . . . . . . . . . . .  8
     4.2.  Capability Definitions . . . . . . . . . . . . . . . . . .  8
   5.  The Location Capability  . . . . . . . . . . . . . . . . . . .  9
     5.1.  Location Capability Summary  . . . . . . . . . . . . . . . 10
   6.  Location Measurement Capability  . . . . . . . . . . . . . . . 10
     6.1.  HELD Measurement Request . . . . . . . . . . . . . . . . . 11
     6.2.  Location Measurement Capability Summary  . . . . . . . . . 11
   7.  XML Schema . . . . . . . . . . . . . . . . . . . . . . . . . . 12
     7.1.  Capabilities Schema  . . . . . . . . . . . . . . . . . . . 12
     7.2.  HELD Measurement Request Schema  . . . . . . . . . . . . . 14
   8.  Security Considerations  . . . . . . . . . . . . . . . . . . . 14
   9.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 15
     9.1.  URN Sub-Namespace Registration for
           urn:ietf:params:xml:ns:held:cap  . . . . . . . . . . . . . 15
     9.2.  URN Sub-Namespace Registration for
           urn:ietf:params:xml:ns:held:cap:location . . . . . . . . . 16
     9.3.  URN Sub-Namespace Registration for
           urn:ietf:params:xml:ns:held:cap:lm . . . . . . . . . . . . 17
     9.4.  XML Schema Registration for HELD Capabilities  . . . . . . 18
     9.5.  URN Sub-Namespace Registration for
           urn:ietf:params:xml:ns:held:mr . . . . . . . . . . . . . . 18
     9.6.  XML Schema Registration for HELD Measurement Request
           and Response . . . . . . . . . . . . . . . . . . . . . . . 19
   10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 19
     10.1. Normative References . . . . . . . . . . . . . . . . . . . 19
     10.2. Informative References . . . . . . . . . . . . . . . . . . 20


















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1.  Introduction

   A device is a good source of information about its location.  Even
   where a device is unable to independently determine its location, it
   can often make observations about its environment and network
   attachment that are of use in determining its position.  Making this
   information available to the Location Information Server (LIS) in the
   access network can improve the quality of location estimates for the
   device.

   Requests that retrieve location information by value are largely
   covered by the measurement information and data formats described in
   [I-D.thomson-geopriv-held-measurements].  However, location
   information provided through location URIs cannot utilise this
   information.

   This document outlines a method whereby a device indicates
   capabilities to a LIS during the creation of a HELD context (see
   [I-D.winterbottom-geopriv-held-context]).  The LIS is able to then
   exercise those capabilities to assist it in the generation of
   location information, or to acquire location information from the
   device.

2.  Conventions used in this document

   This document relies on definitions from a range of specification.
   Use of the terms LIS and Device is consistent with
   [I-D.ietf-geopriv-http-location-delivery].  Location measurement is
   defined in [I-D.thomson-geopriv-held-measurements] and location
   estimate is defined in [I-D.thomson-geopriv-uncertainty].  The term
   context is used as defined in
   [I-D.winterbottom-geopriv-held-context].

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [RFC2119].

3.  Capabilities Exchange Overview

   Acquiring location measurements or information from a device is made
   difficult by the nature of the relationship between the LIS, or
   access network, and the device.  The relationship between a LIS and
   the devices that it serves is often transient.  A device is not
   necessarily a permanent part of an access network.

   HELD [I-D.ietf-geopriv-http-location-delivery] provides a basis for
   the relationship between device and LIS.  LIS Discovery
   [I-D.ietf-geopriv-lis-discovery] provides a means for the device to



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   initiate the relationship.  The relationship is extended to include
   stateful information at the LIS in the form of a context
   [I-D.winterbottom-geopriv-held-context].  This document relies on the
   concept of a HELD context and provides a means for the LIS to acquire
   information from the device.

   This document describes how the context can be used as the basis for
   cooperative location determination.  A device provides the LIS with a
   capabilities indication when it creates or updates its context data.
   The LIS responds with a reciprocal indication, that includes which of
   these capabilities it might use.

   Depending on the specific capabilities that were shared and thereby
   agreed upon, the LIS is able to retrieve location information or
   location measurements from the device.  Device capabilities include
   the ability to generate or acquire location information, or the
   ability to make observations about the mode of network attachment or
   environment.  For instance, a device with GNSS-capable hardware can
   determine its own position by taking a set of measurements and
   performing a calculation, or it can provide the raw measurement data.

   This document defines a set of capabilities that a device can use to
   indicate that it is able to provide location measurements.  The form
   of location measurements is described in
   [I-D.thomson-geopriv-held-measurements].  A device is able to use
   these capabilities to indicate to the LIS the types of measurements
   that it can observe and the means by which the LIS can acquire these
   measurements when needed.  Figure 1 shows a simple scenario where the
   LIS uses a device-provided measurement to service a request to a
   location URI.





















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     +--------+              +-------+          +-----------+
     |        |              |       |          | Location  |
     | Device |              |  LIS  |          | Recipient |
     +--------+              +-------+          +-----------+
         |                       |                    |
         +-----createContext---->|                    |
         |     (capabilities)    |                    |
         |                       |                    |
         |<----contextResponse---+                    |
         |     (capabilities)    |                    |
         |                       |                    |
         | ~ ~ ~ ~ ~ ~ (convey location URI) ~ ~ ~ ~ >|
         |                       |                    |
         |                       |<--locationRequest--+
         |                       |                    |
         |<--measurementRequest--+                    |
         |                       |                    |
         +--measurementResponse->|                    |
         |                       |                    |
         |                       +--locationResponse->|
         |                       |                    |

                         Figure 1: Basic Operation

   This document also defines a location capability, which indicates
   that the device is able to determine its own location.  Guidelines
   for the definition of other capabilities are also included.

3.1.  Capabilities Exchange

   At its core, the capabilities exchange is simple.  The device sends a
   set of capabilities, each identified by a URN, to the LIS inside a
   HELD "createContext" request.  The LIS selects those capabilities
   that it is able to make use of and includes those in the
   "contextResponse" message.

     +--------+                +-------+
     | Device |                |  LIS  |
     +--------+                +-------+
         |                         |
         +------createContext----->|
         |   (capability A, B, C)  |
         |                         |
         |<-----contextResponse----+
         |     (capability A, C)   |
         |                         |

                      Figure 2: Capabilities Exchange



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   The set of capabilities that the LIS includes in the response are a
   subset of the capabilities advertised by the Device.

   Capabilities are related to a single context.  The LIS MUST restrict
   its use of capabilities to requests relating to the context where the
   capabilities are provided by the Device.  The LIS MUST remove and
   pre-existing capabilities from a context when it receives a
   capabilities indication.  Therefore, a Device is able to remove
   capabilities from a context by providing an empty capabilities set.

   Once a common set of capabilities are agreed upon, the LIS is able to
   make use of these capabilities to generate location information.
   This might be an ability to generate geodetic location information at
   the device, or the device might be able provide the LIS with location
   measurements.  The LIS invokes capabilities in response to a request
   for location information, which can be initiated by either the
   device, or a Location Recipient (LR).

     +--------+              +-------+          +-----------+
     |        |              |       |          | Location  |
     | Device |              |  LIS  |          | Recipient |
     +--------+              +-------+          +-----------+
         |                       |                    |
         |                       |<--locationRequest--+
         |                       |                    |
         |<--measurementRequest--+                    |
         |                       |                    |
         +--measurementResponse->|                    |
         |                       |                    |
         |                       +--locationResponse->|
         |                       |                    |


                     Figure 3: Exercising Capabilities

   A capabilities exchange may contain additional information that is
   specific to the associated measurement acquisition method.  This
   additional information allows the Device and LIS to provide more
   information about capabilities.  Agreed capabilities and associated
   parameters can be stored in the context created for the device at the
   LIS for later use.

4.  The Capability Indication

   A "capabilities" element is added to the create context or update
   context HELD requests.  The device initiates the exchange, including
   the "capabilities" element in the request message.  The response from
   the LIS includes a similar element that indicates which of these



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   capabilities might be used.

   A "capabilities" element contains a set of capability indications.  A
   single capability is represented by a "capind" element.  Each
   "capind" element has a mandatory "uri" attribute that contains a URI
   that identifies the capability.

   The "capind" element may also contain arbitrary content, which means
   that the element is able to carry supplementary information that is
   specific to the capability.  This supplementary information could
   include addressing information, protocol selection, authentication
   details, or any data necessary for the successful retrieval of
   information.  Different supplementary information is provided by the
   Device and LIS.

   The "capind" element has an additional optional parameter that
   indicates the expected time that exercising that particular
   capability takes.  This information assists the LIS in a decision on
   whether or not to use this particular capability to serve a request
   for location information.  Note that the Device is only able to
   quantify the time for its own involvement in the process; additional
   delays from network transmission and LIS processing need to be
   included in any decision to exercise a device capability.  The
   "responseTime" attribute is specified as a time in milliseconds.  The
   "responseTime" attribute SHOULD NOT be specified in a response from a
   LIS.

   The following figure shows a capabilities indication that might be
   made by a device with GNSS capabilities.  This uses the location
   capability defined in Section 5, as well as a second capability that
   includes additional parameters.

     <capabilities xmlns="urn:ietf:params:xml:ns:geopriv:held:cap">
       <capind uri="urn:ietf:params:xml:ns:geopriv:held:cap:location"
               responseTime="45000">
         <url>held://192.0.2.55:46743/location/</url>
       </capind>
       <capind uri="urn:ietf:params:xml:ns:geopriv:held:cap:lm"
               responseTime="30">
         <url>held://192.0.2.55:46743/gnss/</url>
         <lm xmlns:gnss="urn:ietf:params:xml:ns:geopriv:lm:gnss">
           gnss:gnss
         </lm>
       </capind>
     </capabilities>






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4.1.  Retrieving Data from the Device

   The capabilities described in this document both rely on the Device
   providing a URL.  The LIS is able to dereference this URL in order to
   retrieve information from the device.  The "url" element is included
   by the Device to indicate where (and how) the information is
   retrieved.

   Although HELD can theoretically be bound to session protocols other
   than HTTP, in effect, HELD capabilities use the questionable practice
   of HTTP callbacks.  For this particular application the drawbacks
   (primarily the fact that it doesn't work very reliably, aside from
   the general disdain it attracts) are considered acceptable for the
   following reasons:

   o  The LIS is expected to exist in close proximity to the device in
      the network, thereby reducing the probability that an intermediate
      node exists that could block the callback.

   o  The LIS is expected to hold a privileged position in the access
      network and may be able to resolve some of the shortcomings of
      this method.

   o  The benefit gained by acquiring measurements might be considered
      worthwhile despite a low probability of success.

4.2.  Capability Definitions

   Capabilities can be defined for access network or location
   measurement technologies as required.  No special registration is
   required to define a capability; each capability is identified by a
   namespace URI.  A capability definition includes the following
   information:

   URI:  A capability is identified by a URI, which need only be unique
      and persistent.  Common practice is to use an "http:" URI for a
      domain that is under the author's control.  An IETF document MUST
      use a URN [RFC2141] that is registered with the IANA.

   Capability Parameters:  Each capability may require additional
      information to be passed between LIS and device in order for it to
      be exercised.  This information must be described and defined as
      XML elements for inclusion in the "capind" element.  Separate
      descriptions and definitions SHOULD be provided for the Device to
      LIS indications and LIS to Device responses.






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   Procedures for Exercising Capabilities:  Each capability MUST also
      include a description of how it can be exercised.  This includes
      the protocol that is used for any network exchanges, the impact of
      each parameter.

   Security and Privacy Implications:  A discussion of the security and
      the privacy implications associated with using the capability MUST
      be included with each definition.

   Author Contact:  Details on how to contact the individual or
      organization responsible for the capability definition.

5.  The Location Capability

   The ability to locate itself is a trait that is applicable to devices
   in a range of networks.  This includes automated location
   determination, like Global Navigation Satellite Systems (GNSS), user
   input, an alternative location service, or a range of location
   techniques.  Because the device produces complete location
   information, there is no need for technology- or network-specific
   features in messages.  Therefore, this section describes how a device
   may advertise its capability to source its own location.

   This section defines a location capability, identified by the URN
   "urn:ietf:params:xml:ns:geopriv:held:cap:location".  This capability
   indicates that the device is able to provide location information to
   the LIS.

   The location capability includes a URI parameter that is passed in
   the request from Device to LIS.  This URI indicates where the LIS can
   retrieve location information.  Any URI scheme that can be trivially
   resolved may be used when expressing this capability.  When using the
   HTTP binding of HELD, it is recommended that this be an "https:" or
   "held:" URI.  The URI should use the same HELD binding as is being
   used for the initial HELD exchange.

   The URI provided by the Device should resolve to a PIDF-LO document
   [RFC4119] containing the location of the Device.  The PIDF-LO MUST be
   current at the time that is requested.  Only the "location-info"
   element of the PIDF-LO SHALL be used by the LIS; therefore, other
   fields of the PIDF-LO MAY be minimally populated.

   If the provided URI is an "http:" URL, a GET request MUST yield a
   PIDF-LO in the response.  If the URI is a "held:" URI, the LIS MUST
   follow the rules in [I-D.winterbottom-geopriv-deref-protocol] when
   requesting information.  The Device includes the PIDF-LO in a
   location response message.  In the HELD request, the LIS SHOULD NOT
   request a specific location type; in particular, the LIS MUST NOT



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   request a location URI from the Device.

   In providing location information in this manner, the Device
   implicitly grants the LIS the ability to redistribute location
   information under the same conditions that apply to the HELD context.

5.1.  Location Capability Summary

   The following summarizes the location capability following the
   outline from Section 4.2:

   URI:  urn:ietf:params:xml:ns:geopriv:held:cap:location

   Capability Parameters:  This capability has a single parameter, a URL
      that is included in a "url" element.  The "url" element is only
      used in the Device to LIS capabilities indication.

   Procedures for Exercising Capabilities:  This capability is exercised
      by resolving and dereferencing a URL.

   Security and Privacy Implications:  See Section 8 of this document.

   Author Contact:  The authors of this document.

6.  Location Measurement Capability

   Like the ability to generate location information, acquiring
   measurement data from the Device can be invaluable to the LIS.
   Measurement information from a device can improve the accuracy of
   location estimates or enable positioning methods that would not
   otherwise be available.  See [I-D.thomson-geopriv-held-measurements]
   for more information on location measurements.

   The measurement capability is identified by the URN
   "urn:ietf:params:xml:ns:geopriv:held:cap:lm".  In addition to this
   URN, the Device also needs to indicate which measurements it can
   provide in the capability indication.  This is done by identifying
   the location measurement element.

   The "lm" element includes a qualified element name (using the
   namespace context of the enclosing document).  This name identifies a
   measurement element, as defined by the guidelines in
   [I-D.thomson-geopriv-held-measurements].

   When the LIS dereferences the provided URL, the Device acquires
   location measurements and provides these in response.  If an HTTP URI
   is provided, the response is an "appplication/xml" document
   containing a "measurements" element.  If a HELD URI is used, the HELD



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   measurement request and measurement response are used, as defined in
   Section 6.1.

6.1.  HELD Measurement Request

   A HELD measurement request is defined by a "measurementRequest"
   element.  A HELD measurement request has a single parameter,
   "responseTime", which has the same semantics as the response time
   parameter on a location request (see
   [I-D.ietf-geopriv-http-location-delivery]).  Figure 4 contains an
   example measurement request message.

     <measurementRequest xmlns="urn:ietf:params:xml:ns:geopriv:held:mr"
                         responseTime="3000"/>

                   Figure 4: Example Measurement Request

   The measurement response contains measurements, in the form of a
   "measurements" element (see [I-D.thomson-geopriv-held-measurements]).
   Figure 5 contains an example measurement response message.

     <measurementResponse
         xmlns="urn:ietf:params:xml:ns:geopriv:held:mr">
          <wifi xmlns="urn:ietf:params:xml:ns:geopriv:lm:wifi">
            <servingWap>
              <ssid>wlan-home</ssid>
              <bssid>00-12-F0-A0-80-EF</bssid>
            </servingWap>
          </wifi>
       </measurements>
     </measurementResponse>

                  Figure 5: Example Measurement Response

   The HELD measurement request and response are defined in the
   "urn:ietf:params:xml:ns:geopriv:held:mr" namespace and use the
   "application/held+xml" MIME type.

   For privacy purposes, the Device implicitly grants the LIS the
   ability to redistribute location information derived from the
   location measurements it provides under the same conditions that
   apply to the HELD context.

6.2.  Location Measurement Capability Summary

   The following summarizes the location measurement capability
   following the outline from Section 4.2:




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   URI:  urn:ietf:params:xml:ns:geopriv:held:cap:lm

   Capability Parameters:  This capability has two parameters: a URL
      that is included in a "url" element; and a qualified element name
      that is included in the "lm" element.  These parameters are only
      used in the Device to LIS capabilities indication.

   Procedures for Exercising Capabilities:  This capability is exercised
      by resolving and dereferencing a URL.  If the URL is a "held:"
      URL, a HELD measurement request (see Section 6.1) is used.

   Security and Privacy Implications:  See Section 8 of this document.

   Author Contact:  The authors of this document.

7.  XML Schema

   This section includes a definition for the capabilities exchange
   element (Section 7.1) and a definition of HELD measurement request
   and response messages (Section 7.2).

7.1.  Capabilities Schema

   <?xml version="1.0"?>
   <xs:schema
        xmlns:cap="urn:ietf:params:xml:ns:geopriv:held:cap"
        xmlns:xs="http://www.w3.org/2001/XMLSchema"
        targetNamespace="urn:ietf:params:xml:ns:geopriv:held:cap"
        elementFormDefault="qualified"
        attributeFormDefault="unqualified">

     <xs:annotation>
       <xs:appinfo
           source="urn:ietf:params:xml:schema:geopriv:held:cap">
         HELD Capabilities
       </xs:appinfo>
       <xs:documentation source="http://www.ietf.org/rfc/rfcXXXX.txt">
   <!-- [[NOTE TO RFC-EDITOR: Please replace above URL with URL of
                          published RFC and remove this note.]] -->
         This schema defines a framework for capabilities negotiation
         in HELD.
       </xs:documentation>
     </xs:annotation>

     <xs:element name="capabilities">
       <xs:complexType>
         <xs:complexContent>
           <xs:restriction base="xs:anyType">



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             <xs:sequence>
               <xs:element ref="cap:capind"
                           minOccurs="0" maxOccurs="unbounded"/>
               <xs:any namespace="##other" processContents="lax"
                       minOccurs="0" maxOccurs="unbounded"/>
             </xs:sequence>
             <xs:anyAttribute namespace="##any" processContents="lax"/>
           </xs:restriction>
         </xs:complexContent>
       </xs:complexType>
     </xs:element>

     <xs:element name="capind">
       <xs:complexType>
         <xs:complexContent>
           <xs:restriction base="xs:anyType">
             <xs:sequence>
               <xs:any namespace="##any" processContents="lax"
                       minOccurs="0" maxOccurs="unbounded"/>
             </xs:sequence>
             <xs:attribute name="uri" type="xs:anyURI" use="required"/>
             <xs:attribute name="responseTime" type="cap:durationType"
                           use="optional"/>
             <xs:anyAttribute namespace="##any" processContents="lax"/>
           </xs:restriction>
         </xs:complexContent>
       </xs:complexType>
     </xs:element>

     <xs:simpleType name="durationType">
       <xs:restriction base="xs:decimal">
         <xs:minInclusive value="0.0"/>
       </xs:restriction>
     </xs:simpleType>

     <!-- Location measurement element -->
     <xs:element name="lm" type="cap:lmType"/>
     <xs:complexType name="lmType">
       <xs:simpleContent>
         <xs:extension base="xs:Name">
           <xs:anyAttribute namespace="##any" processContents="lax"/>
         </xs:extension>
       </xs:simpleContent>
     </xs:complexType>

     <!-- Callback URI element -->
     <xs:element name="url" type="xs:anyURI"/>




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   </xs:schema>

7.2.  HELD Measurement Request Schema

   <?xml version="1.0"?>
   <xs:schema
        xmlns:mr="urn:ietf:params:xml:ns:geopriv:held:mr"
        xmlns:held="urn:ietf:params:xml:ns:geopriv:held"
        xmlns:xs="http://www.w3.org/2001/XMLSchema"
        targetNamespace="urn:ietf:params:xml:ns:geopriv:held:mr"
        elementFormDefault="qualified"
        attributeFormDefault="unqualified">

     <xs:annotation>
       <xs:appinfo
           source="urn:ietf:params:xml:schema:geopriv:held:mr">
         HELD Capabilities
       </xs:appinfo>
       <xs:documentation source="http://www.ietf.org/rfc/rfcXXXX.txt">
   <!-- [[NOTE TO RFC-EDITOR: Please replace above URL with URL of
                          published RFC and remove this note.]] -->
         This schema defines the HELD measurement request and response.
       </xs:documentation>
     </xs:annotation>

     <xs:import namespace="urn:ietf:params:xml:ns:geopriv:held"/>

     <xs:element name="measurementRequest" type="held:baseRequestType"/>
     <xs:element name="measurementResponse" type="xs:anyType"/>

   </xs:schema>

8.  Security Considerations

   Giving the LIS additional information about the location of a Device
   might consititute a compromise of privacy.  The LIS is able to
   resolve the location of the Device with greater accuracy than would
   be otherwise possible without this assistance.  Information about the
   capabilities of a Device could also be considered sensitive.  A
   Device SHOULD offer a user the option to suppress the capability
   exchange and all associated functions.

   Capabilities MUST only be exchanged with the LIS in the scope of a
   context.  This precaution provides the Device with a means to void
   access to these capabilities at any time.  This can be done by
   deleting the context, or by indicating an empty set of capabilities
   to the LIS.




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   Any information that is provided to the LIS by the Device increases
   the impact of LIS impersonation.  Measures that mitigate the
   possibility of impersonation, as outlined in
   [I-D.ietf-geopriv-lis-discovery], are more important for a Device
   that provides capability information to a LIS.  Protocols used for
   the exchange of location information or location measurements should
   also provide protection from eavesdropping.

   When the LIS contacts the Device, the Device SHOULD authenticate the
   LIS using the same credentials provided by the LIS after discovery
   (see [I-D.ietf-geopriv-lis-discovery]).  This ensures that other
   entities are not able to retrieve location information or
   measurements from the Device.  Requiring client authentication on a
   TLS connection and then matching this authentication to the server
   authentication provided by the LIS can achieve this.

   The LIS is responsible for the veracity of location information it
   provides, even when it relies on information that comes from the
   Device.  However, the LIS is not necessarily able to establish
   grounds for trust in this information.  A Device could provide
   erroneous measurements in an attempt to make the LIS provide
   incorrect or fraudulent location information.  The LIS should take
   measures to verify the information that is provided to it before
   acting on those data.  The LIS can use information from the network,
   or other trusted sources, to check that information provided by the
   Device is valid.

9.  IANA Considerations

   This section registers URNs for XML namespaces of capabilities
   (Section 9.1) and the HELD measurement request and response
   (Section 9.5).  Corresponding schemas are also registered
   (Section 9.4, Section 9.6).  URNs are registered for the location
   (Section 9.2) and location measurement (Section 9.3) capability URIs.

9.1.  URN Sub-Namespace Registration for urn:ietf:params:xml:ns:held:cap

   This section registers a new XML namespace,
   "urn:ietf:params:xml:ns:held:cap", as per the guidelines in
   [RFC3688].

      URI: urn:ietf:params:xml:ns:held:cap

      Registrant Contact: IETF, GEOPRIV working group,
      (geopriv@ietf.org), Martin Thomson (martin.thomson@andrew.com).

      XML:




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         BEGIN
           <?xml version="1.0"?>
           <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
             "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
           <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">
             <head>
               <title>HELD Capabilities Indication</title>
             </head>
             <body>
               <h1>Namespace for HELD Capabilities Indication</h1>
               <h2>urn:ietf:params:xml:ns:held:cap</h2>
   [[NOTE TO IANA/RFC-EDITOR: Please update RFC URL and replace XXXX
       with the RFC number for this specification.]]
               <p>See <a href="[[RFC URL]]">RFCXXXX</a>.</p>
             </body>
           </html>
         END

9.2.  URN Sub-Namespace Registration for
      urn:ietf:params:xml:ns:held:cap:location

   This section registers a new XML namespace,
   "urn:ietf:params:xml:ns:held:cap:location", as per the guidelines in
   [RFC3688].

      URI: urn:ietf:params:xml:ns:held:cap:location

      Registrant Contact: IETF, GEOPRIV working group,
      (geopriv@ietf.org), Martin Thomson (martin.thomson@andrew.com).

      XML:




















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         BEGIN
           <?xml version="1.0"?>
           <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
             "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
           <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">
             <head>
               <title>HELD Capabilities - Location Capability</title>
             </head>
             <body>
               <h1>Namespace for HELD Capabilities
                   - Location Capability</h1>
               <h2>urn:ietf:params:xml:ns:held:cap:location</h2>
   [[NOTE TO IANA/RFC-EDITOR: Please update RFC URL and replace XXXX
       with the RFC number for this specification.]]
               <p>See <a href="[[RFC URL]]">RFCXXXX</a>.</p>
             </body>
           </html>
         END

9.3.  URN Sub-Namespace Registration for
      urn:ietf:params:xml:ns:held:cap:lm

   This section registers a new XML namespace,
   "urn:ietf:params:xml:ns:held:cap:lm", as per the guidelines in
   [RFC3688].

      URI: urn:ietf:params:xml:ns:held:cap:lm

      Registrant Contact: IETF, GEOPRIV working group,
      (geopriv@ietf.org), Martin Thomson (martin.thomson@andrew.com).

      XML:



















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         BEGIN
           <?xml version="1.0"?>
           <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
             "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
           <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">
             <head>
               <title>HELD Capabilities
                      - Location Measurement Capability</title>
             </head>
             <body>
               <h1>Namespace for HELD Capabilities
                   - Location Measurement Capability</h1>
               <h2>urn:ietf:params:xml:ns:held:cap:lm</h2>
   [[NOTE TO IANA/RFC-EDITOR: Please update RFC URL and replace XXXX
       with the RFC number for this specification.]]
               <p>See <a href="[[RFC URL]]">RFCXXXX</a>.</p>
             </body>
           </html>
         END

9.4.  XML Schema Registration for HELD Capabilities

   This section registers an XML schema as per the guidelines in
   [RFC3688].

   URI:  urn:ietf:params:xml:schema:held:cap

   Registrant Contact:  IETF, GEOPRIV working group, (geopriv@ietf.org),
      Martin Thomson (martin.thomson@andrew.com).

   Schema:  The XML for this schema can be found as the entirety of
      Section 7.1 of this document.

9.5.  URN Sub-Namespace Registration for urn:ietf:params:xml:ns:held:mr

   This section registers a new XML namespace,
   "urn:ietf:params:xml:ns:held:mr", as per the guidelines in [RFC3688].

      URI: urn:ietf:params:xml:ns:held:mr

      Registrant Contact: IETF, GEOPRIV working group,
      (geopriv@ietf.org), Martin Thomson (martin.thomson@andrew.com).

      XML:







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         BEGIN
           <?xml version="1.0"?>
           <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
             "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
           <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">
             <head>
               <title>HELD Measurement Request/Response</title>
             </head>
             <body>
               <h1>Namespace for HELD Request/Response</h1>
               <h2>urn:ietf:params:xml:ns:held:mr</h2>
   [[NOTE TO IANA/RFC-EDITOR: Please update RFC URL and replace XXXX
       with the RFC number for this specification.]]
               <p>See <a href="[[RFC URL]]">RFCXXXX</a>.</p>
             </body>
           </html>
         END

9.6.  XML Schema Registration for HELD Measurement Request and Response

   This section registers an XML schema as per the guidelines in
   [RFC3688].

   URI:  urn:ietf:params:xml:schema:held:mr

   Registrant Contact:  IETF, GEOPRIV working group, (geopriv@ietf.org),
      Martin Thomson (martin.thomson@andrew.com).

   Schema:  The XML for this schema can be found as the entirety of
      Section 7.2 of this document.

10.  References

10.1.  Normative References

   [RFC2119]                                  Bradner, S., "Key words
                                              for use in RFCs to
                                              Indicate Requirement
                                              Levels", BCP 14, RFC 2119,
                                              March 1997.

   [I-D.ietf-geopriv-http-location-delivery]  Barnes, M., Winterbottom,
                                              J., Thomson, M., and B.
                                              Stark, "HTTP Enabled
                                              Location Delivery (HELD)",
                                              draft-ietf-geopriv-http-
                                              location-delivery-07 (work
                                              in progress), April 2008.



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   [I-D.ietf-geopriv-lis-discovery]           Thomson, M. and J.
                                              Winterbottom, "Discovering
                                              the Local Location
                                              Information Server (LIS)",
                                              draft-ietf-geopriv-lis-
                                              discovery-01 (work in
                                              progress), June 2008.

   [I-D.winterbottom-geopriv-held-context]    Winterbottom, J.,
                                              Tschofenig, H., and M.
                                              Thomson, "HELD Protocol
                                              Context Management
                                              Extensions", draft-
                                              winterbottom-geopriv-held-
                                              context-02 (work in
                                              progress), February 2008.

   [I-D.thomson-geopriv-held-measurements]    Thomson, M. and J.
                                              Winterbottom, "Using
                                              Device-provided Location-
                                              Related Measurements in
                                              HELD", draft-thomson-
                                              geopriv-held-measurements-
                                              02 (work in progress),
                                              May 2008.

   [I-D.winterbottom-geopriv-deref-protocol]  Winterbottom, J.,
                                              Tschofenig, H.,
                                              Schulzrinne, H., Thomson,
                                              M., and M. Dawson, "An
                                              HTTPS Location
                                              Dereferencing Protocol
                                              Using HELD", draft-
                                              winterbottom-geopriv-
                                              deref-protocol-00 (work in
                                              progress), November 2007.

10.2.  Informative References

   [RFC2141]                                  Moats, R., "URN Syntax",
                                              RFC 2141, May 1997.

   [RFC3688]                                  Mealling, M., "The IETF
                                              XML Registry", BCP 81,
                                              RFC 3688, January 2004.

   [RFC4119]                                  Peterson, J., "A Presence-
                                              based GEOPRIV Location



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                                              Object Format", RFC 4119,
                                              December 2005.

   [I-D.thomson-geopriv-uncertainty]          Thomson, M. and J.
                                              Winterbottom,
                                              "Representation of
                                              Uncertainty and Confidence
                                              in PIDF-LO", draft-
                                              thomson-geopriv-
                                              uncertainty-01 (work in
                                              progress), June 2008.

Authors' Addresses

   Martin Thomson
   Andrew
   PO Box U40
   Wollongong University Campus, NSW  2500
   AU

   Phone: +61 2 4221 2915
   EMail: martin.thomson@andrew.com
   URI:   http://www.andrew.com/


   James Winterbottom
   Andrew
   PO Box U40
   Wollongong University Campus, NSW  2500
   AU

   Phone: +61 2 4221 2938
   EMail: james.winterbottom@andrew.com
   URI:   http://www.andrew.com/

















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Full Copyright Statement

   Copyright (C) The IETF Trust (2008).

   This document is subject to the rights, licenses and restrictions
   contained in BCP 78, and except as set forth therein, the authors
   retain all their rights.

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   "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
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   The IETF invites any interested party to bring to its attention any
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