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GEOPRIV                                                       M. Thomson
Internet-Draft                                           J. Winterbottom
Intended status: Standards Track                                  Andrew
Expires: November 28, 2010                                  May 27, 2010


    Using Device-provided Location-Related Measurements in Location
                        Configuration Protocols
               draft-thomson-geopriv-held-measurements-06

Abstract

   A method is described by which a Device is able to provide location-
   related measurement data to a LIS within a request for location
   information.  Location-related measurement information are
   observations concerning properties related to the position of a
   Device, which could be data about network attachment or about the
   physical environment.  When a LIS generates location information for
   a Device, information from the Device can improve the accuracy of the
   location estimate.  A basic set of location-related measurements are
   defined, including common modes of network attachment as well as
   assisted Global Navigation Satellite System (GNSS) parameters.

Status of this Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
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   Drafts is at http://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
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   This Internet-Draft will expire on November 28, 2010.

Copyright Notice

   Copyright (c) 2010 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of



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   publication of this document.  Please review these documents
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   it for publication as an RFC or to translate it into languages other
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Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  5
   2.  Conventions used in this document  . . . . . . . . . . . . . .  5
   3.  Location-Related Measurements in LCPs  . . . . . . . . . . . .  6
   4.  Location-Related Measurement Data Types  . . . . . . . . . . .  7
     4.1.  Measurement Container  . . . . . . . . . . . . . . . . . .  8
       4.1.1.  Time of Measurement  . . . . . . . . . . . . . . . . .  8
       4.1.2.  Expiry Time on Location-Related Measurement Data . . .  8
     4.2.  RMS Error and Number of Samples  . . . . . . . . . . . . .  9
       4.2.1.  Time RMS Error . . . . . . . . . . . . . . . . . . . .  9
     4.3.  Measurement Request  . . . . . . . . . . . . . . . . . . . 10
     4.4.  Identifying Location Provenance  . . . . . . . . . . . . . 11
   5.  Location-Related Measurement Data Types  . . . . . . . . . . . 13
     5.1.  LLDP Measurements  . . . . . . . . . . . . . . . . . . . . 13
     5.2.  DHCP Relay Agent Information Measurements  . . . . . . . . 13
     5.3.  802.11 WLAN Measurements . . . . . . . . . . . . . . . . . 14
       5.3.1.  Wifi Measurement Requests  . . . . . . . . . . . . . . 16
     5.4.  Cellular Measurements  . . . . . . . . . . . . . . . . . . 17
       5.4.1.  Cellular Measurement Requests  . . . . . . . . . . . . 20
     5.5.  GNSS Measurements  . . . . . . . . . . . . . . . . . . . . 20
       5.5.1.  GNSS System and Signal . . . . . . . . . . . . . . . . 22
       5.5.2.  Time . . . . . . . . . . . . . . . . . . . . . . . . . 23
       5.5.3.  Per-Satellite Measurement Data . . . . . . . . . . . . 23
       5.5.4.  GNSS Measurement Requests  . . . . . . . . . . . . . . 24
     5.6.  DSL Measurements . . . . . . . . . . . . . . . . . . . . . 24
       5.6.1.  L2TP Measurements  . . . . . . . . . . . . . . . . . . 25
       5.6.2.  RADIUS Measurements  . . . . . . . . . . . . . . . . . 25
       5.6.3.  Ethernet VLAN Tag Measurements . . . . . . . . . . . . 26
       5.6.4.  ATM Virtual Circuit Measurements . . . . . . . . . . . 26
   6.  Measurement Schemas  . . . . . . . . . . . . . . . . . . . . . 26
     6.1.  Measurement Container Schema . . . . . . . . . . . . . . . 27
     6.2.  Measurement Source Schema  . . . . . . . . . . . . . . . . 29
     6.3.  Base Type Schema . . . . . . . . . . . . . . . . . . . . . 29
     6.4.  LLDP Measurement Schema  . . . . . . . . . . . . . . . . . 32
     6.5.  DHCP Measurement Schema  . . . . . . . . . . . . . . . . . 33
     6.6.  WiFi Measurement Schema  . . . . . . . . . . . . . . . . . 35
     6.7.  Cellular Measurement Schema  . . . . . . . . . . . . . . . 37
     6.8.  GNSS Measurement Schema  . . . . . . . . . . . . . . . . . 39
     6.9.  DSL Measurement Schema . . . . . . . . . . . . . . . . . . 41
   7.  Privacy Considerations . . . . . . . . . . . . . . . . . . . . 43
     7.1.  Measurement Data Privacy Model . . . . . . . . . . . . . . 43
     7.2.  LIS Privacy Requirements . . . . . . . . . . . . . . . . . 44
     7.3.  Measurement Data and Location URIs . . . . . . . . . . . . 44
     7.4.  Third-Party-Provided Measurement Data  . . . . . . . . . . 44
   8.  Security Considerations  . . . . . . . . . . . . . . . . . . . 45
     8.1.  Threat Model . . . . . . . . . . . . . . . . . . . . . . . 45
       8.1.1.  Acquiring Location Information Without



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               Authorization  . . . . . . . . . . . . . . . . . . . . 45
       8.1.2.  Extracting Network Topology Data . . . . . . . . . . . 46
       8.1.3.  Lying By Proxy . . . . . . . . . . . . . . . . . . . . 47
       8.1.4.  Measurement Replay . . . . . . . . . . . . . . . . . . 48
     8.2.  Mitigation . . . . . . . . . . . . . . . . . . . . . . . . 48
       8.2.1.  Measurement Validation . . . . . . . . . . . . . . . . 49
       8.2.2.  Location Validation  . . . . . . . . . . . . . . . . . 50
       8.2.3.  Supporting Observations  . . . . . . . . . . . . . . . 51
       8.2.4.  Attribution  . . . . . . . . . . . . . . . . . . . . . 53
       8.2.5.  Stateful Correlation of Location Requests  . . . . . . 54
   9.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 54
     9.1.  IANA Registry for GNSS Types . . . . . . . . . . . . . . . 54
     9.2.  URN Sub-Namespace Registration for
           urn:ietf:params:xml:ns:pidf:geopriv10:lmsrc  . . . . . . . 55
     9.3.  URN Sub-Namespace Registration for
           urn:ietf:params:xml:ns:geopriv:lm  . . . . . . . . . . . . 56
     9.4.  URN Sub-Namespace Registration for
           urn:ietf:params:xml:ns:geopriv:lm:basetypes  . . . . . . . 57
     9.5.  URN Sub-Namespace Registration for
           urn:ietf:params:xml:ns:geopriv:lm:lldp . . . . . . . . . . 57
     9.6.  URN Sub-Namespace Registration for
           urn:ietf:params:xml:ns:geopriv:lm:dhcp . . . . . . . . . . 58
     9.7.  URN Sub-Namespace Registration for
           urn:ietf:params:xml:ns:geopriv:lm:wifi . . . . . . . . . . 59
     9.8.  URN Sub-Namespace Registration for
           urn:ietf:params:xml:ns:geopriv:lm:cell . . . . . . . . . . 59
     9.9.  URN Sub-Namespace Registration for
           urn:ietf:params:xml:ns:geopriv:lm:gnss . . . . . . . . . . 60
     9.10. URN Sub-Namespace Registration for
           urn:ietf:params:xml:ns:geopriv:lm:dsl  . . . . . . . . . . 61
     9.11. XML Schema Registration for Measurement Source Schema  . . 61
     9.12. XML Schema Registration for Measurement Container
           Schema . . . . . . . . . . . . . . . . . . . . . . . . . . 62
     9.13. XML Schema Registration for Base Types Schema  . . . . . . 62
     9.14. XML Schema Registration for LLDP Schema  . . . . . . . . . 62
     9.15. XML Schema Registration for DHCP Schema  . . . . . . . . . 62
     9.16. XML Schema Registration for WiFi Schema  . . . . . . . . . 63
     9.17. XML Schema Registration for Cellular Schema  . . . . . . . 63
     9.18. XML Schema Registration for GNSS Schema  . . . . . . . . . 63
     9.19. XML Schema Registration for DSL Schema . . . . . . . . . . 64
   10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 64
   11. References . . . . . . . . . . . . . . . . . . . . . . . . . . 64
     11.1. Normative References . . . . . . . . . . . . . . . . . . . 64
     11.2. Informative References . . . . . . . . . . . . . . . . . . 65
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 66






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1.  Introduction

   A location configuration protocol (LCP) provides a means for a Device
   to request information about its physical location from an access
   network.  A location information server (LIS) is the server that
   provides location information; information that is available due to
   the knowledge about the network and physical environment that is
   available to the LIS.

   As a part of the access network, the LIS is able to acquire
   measurement results from network Devices within the network that are
   related to Device location.  The LIS also has access to information
   about the network topology that can be used to turn measurement data
   into location information.  However, this information can be enhanced
   with information acquired from the Device itself.

   A Device is able to make observations about its network attachment,
   or its physical environment.  The location-related measurement data
   might be unavailable to the LIS; alternatively, the LIS might be able
   to acquire the data, but at a higher cost in time or otherwise.
   Providing measurement data gives the LIS more options in determining
   location, which could improve the quality of the service provided by
   the LIS.  Improvements in accuracy are one potential gain, but
   improved response times and lower error rates are also possible.

   This document describes a means for a Device to report location-
   related measurement data to the LIS.  Examples based on the HELD
   [I-D.ietf-geopriv-http-location-delivery] location configuration
   protocol are provided.


2.  Conventions used in this document

   The terms LIS and Device are used in this document in a manner
   consistent with the usage in
   [I-D.ietf-geopriv-http-location-delivery].

   This document also uses the following definitions:

   Location Measurement:  An observation about the physical properties
      of a particular Device's network access.  The result of a location
      measurement--"location-related measurement data", or simply
      "measurement data" given sufficient context--can be used to
      determine the location of a Device.  Location-related measurement
      data does not identify a Device; measurement data can change with
      time if the location of the Device also changes.

      Location-related measurement data does not necessarily contain



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      location information directly, but it can be used in combination
      with contextual knowledge of the network, or algorithms to derive
      location information.  Examples of location-related measurement
      data are: radio signal strength or timing measurements, Ethernet
      switch and port identifiers.

      Location-related measurement data can be considered sighting
      information, based on the definition in [RFC3693].

   Location Estimate:  The result of location determination, a location
      estimate is an approximation of where the Device is located.
      Location estimates are subject to uncertainty, which arise from
      errors in measurement results.

   GNSS:  Global Navigation Satellite System.  A satellite-based system
      that provides positioning and time information.  For example, the
      US Global Positioning System (GPS) or the European Galileo system.

   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.  Location-Related Measurements in LCPs

   This document defines a standard container for the conveyance of
   location-related measurement parameters in location configuration
   protocols.  This is an XML container that identifies parameters by
   type and allows the Device to provide the results of any measurement
   it is able to perform.  A set of measurement schemas are also defined
   that can be carried in the generic container.

   The simplest example of measurement data conveyance is illustrated by
   the example message in Figure 1.  This shows a HELD location request
   message with an Ethernet switch and port measurement taken using LLDP
   [IEEE.8021AB].

     <locationRequest xmlns="urn:ietf:params:xml:ns:geopriv:held">
       <locationType exact="true">civic</locationType>
       <measurements xmlns="urn:ietf:params:xml:ns:geopriv:lm"
                     time="2008-04-29T14:33:58">
         <lldp xmlns="urn:ietf:params:xml:ns:geopriv:lm:lldp">
           <chassis type="4">0a01003c</chassis>
           <port type="6">c2</port>
         </lldp>
       </measurements>
     </locationRequest>




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           Figure 1: HELD Location Request with Measurement Data

   Measurement data that the LIS does not support or understand can be
   ignored.  The measurements defined in this document follow this rule;
   extensions that could result in backward incompatibility MUST be
   added as new measurement definitions rather than extensions to
   existing types.

   Multiple sets of measurement data, either of the same type or from
   different sources can be included in the "measurements" element.  See
   Section 4.1.1 for details on repetition of this element.

   Use of location-related measurement data is at the discretion of the
   LIS, but the "method" parameter in the PIDF-LO SHOULD be adjusted to
   reflect the method used.

   Location-related measurement data need not be provided exclusively by
   Devices.  A third party location requester can request location
   information using measurement data, if they are able and authorized.
   There are privacy considerations relating to the use of measurements
   by third parties, which are discussed in Section 7.4.

   Location-related measurement data and its use presents a number of
   security challenges.  These are described in more detail in
   Section 8.


4.  Location-Related Measurement Data Types

   A common container is defined for the expression of location
   measurement data, as well as a simple means of identifying specific
   types of measurement data for the purposes of requesting them.

   The following example shows a measurement container with measurement
   time and expiration time included.  A WiFi measurement is enclosed.

     <lm:measurements xmlns:lm="urn:ietf:params:xml:ns:geopriv:lm"
                      time="2008-04-29T14:33:58"
                      expires="2008-04-29T17:33:58">
       <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>
     </lm:measurements>

                       Figure 2: Measurement Example



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4.1.  Measurement Container

   The "measurement" element is used to encapsulate measurement data
   that is collected at a certain point in time.  It contains time-based
   attributes that are common to all forms of measurement data, and
   permits the inclusion of arbitrary measurement data.

   This container can be added to any request for location information,
   such as a HELD location request
   [I-D.ietf-geopriv-http-location-delivery].

4.1.1.  Time of Measurement

   The "time" attribute records the time that the measurement or
   observation was made.  This time can be different to the time that
   the measurement information was reported.  Time information can be
   used to populate a timestamp on the location result, or to determine
   if the measurement information is used.

   The "time" attribute is optional to avoid forcing an arbitrary choice
   of timestamp for relatively static types of measurement (for
   instance, the DSL measurements in Section 5.6) and for legacy Devices
   that don't record time information (such as the Home Location
   Register/Home Subscriber Server for cellular).  However, time SHOULD
   be provided whenever possible.

   The "time" attribute is attached to the root "measurement" element.
   If it is necessary to provide multiple sets of measurement data with
   different times, multiple "measurement" elements SHOULD be provided.

4.1.2.  Expiry Time on Location-Related Measurement Data

   A Device is able to indicate an expiry time in the location
   measurement using the "expires" attribute.  Nominally, this attribute
   indicates how long information is expected to be valid for, but it
   can also indicate a time limit on the retention and use of the
   measurement data.  A Device can use this attribute to prevent the LIS
   from retaining measurement data or limit the time that a LIS retains
   this information.

   Note:  Movement of a Device might result in the measurement data
      being invalidated before the expiry time.

   The LIS MUST NOT keep location-related measurement data beyond the
   time indicated in the "expires" attribute.






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4.2.  RMS Error and Number of Samples

   Often a measurement is taken more than once over a period of time.
   Reporting the average of a number of measurement results mitigates
   the effects of random errors that occur in the measurement process.
   Typically, a mean value is reported at the end of the measurement
   interval, but additional information about the distribution of the
   results can be useful in determining location uncertainty.

   Two optional attributes are provided for certain measurement values:

   rmsError:  The root-mean-squared (RMS) error of the set of
      measurement values used in calculating the result.  RMS error is
      expressed in the same units as the measurement, unless otherwise
      stated.  If an accurate value for RMS error is not known, this
      value can be used to indicate an upper bound for the RMS error.

   samples:  The number of samples that were taken in determining the
      measurement value.  If omitted, this value can be assumed to be a
      very large value, so that the RMS error is an indication of the
      standard deviation of the sample set.

   For some measurement techniques, measurement error is largely
   dependent on the measurement technique employed.  In these cases,
   measurement error is largely a product of the measurement technique
   and not the specific circumstances, so RMS error does not need to be
   actively measured.  A fixed value MAY be provided for RMS error where
   appropriate.

   The "rmsError" and "samples" elements are added as attributes of
   specific measurement data types.

4.2.1.  Time RMS Error

   Measurement of time can be significant in certain circumstances.  The
   GNSS measurements included in this document are one such case where a
   small error in time can result in a large error in location.  Factors
   such as clock drift and errors in time sychronization can result in
   small, but significant, time errors.  Including an indication of the
   quality of the time can be helpful.

   An optional "timeError" attribute can be added to the "measurement"
   element to indicate the RMS error in time. "timeError" indicates an
   upper bound on the time RMS error in seconds.

   The "timeError" attribute does not apply where multiple samples of a
   measurement is taken over time.  If multiple samples are taken, each
   SHOULD be included in a different "measurement" element.



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4.3.  Measurement Request

   A measurement request is used by a protocol peer to describe a set of
   measurement data that it desires.  A "measurementRequest" element is
   defined that can be included in a protocol exchange.

   For instance, a LIS can use a measurement request in HELD responses.
   If the LIS is unable to provide location information, but it believes
   that a particular measurement type would enable it to provide a
   location, it can include a measurement request in an error response.

   The "measurement" element of the measurement request identifies the
   type of measurement that is requested.  The "type" attribute of this
   element indicates the type of measurement, as identified by an XML
   qualified name.  An optional "samples" attribute indicates how many
   samples of the identified measurement are requested.

   The "measurement" element can be repeated to request multiple (or
   alternative) measurement types.

   Additional XML content might be defined for a particular measurement
   type that is used to further refine a request.  These elements either
   constrain what is requested or specify optional components of the
   measurement data that are needed.  These are defined along with the
   specific measurement type.

   In the HELD protocol, the inclusion of a measurement request in a
   error response with a code of "locationUnknown" indicates that the
   LIS believes that providing the indicated measurements would increase
   the likelihood of a subsequent request being successful.

   The following example shows a HELD error response that indicates that
   WiFi measurement data would be useful if a later request were made.
   Additional elements indicate that received signal strength for an
   802.11n access point is requested.

     <error xmlns="urn:ietf:params:xml:ns:geopriv:held"
            code="locationUnknown">
       <message xml:lang="en">Insufficient measurement data</message>
       <measurementRequest
           xmlns="urn:ietf:params:xml:ns:geopriv:lm"
           xmlns:wifi="urn:ietf:params:xml:ns:geopriv:lm:wifi">
         <measurement type="wifi:wifi">
           <wifi:type>n</wifi:type>
           <wifi:parameters>wifi:rssi</wifi:parameters>
         </measurement>
       </measurementRequest>
     </error>



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                                 Figure 3

   A measurement request that is included in other HELD messages has
   undefined semantics and can be safely ignored.  Other specifications
   might define semantics for measurement requests under other
   conditions.

4.4.  Identifying Location Provenance

   An extension is made to the PIDF-LO [RFC4119] that allows a location
   recipient to identify the source (or sources) of location information
   and the measurement data that was used to determine that location
   information.

   The "source" element is added to the "geopriv" element of the
   PIDF-LO.  This element does not identify specific entities.  Instead,
   it identifies the type of source.

   The following types of measurement source are identified:

   lis:  Location information is based on measurement data that the LIS
      or sources that it trusts have acquired.  This label might be used
      if measurement data provided by the Device has been completely
      validated by the LIS.

   device:  Location information is based on measurement data that the
      Device has provided to the LIS.

   other:  Location information is based on measurement data that a
      third party has provided.  This might be an authorized third party
      that uses identity parameters
      [I-D.ietf-geopriv-held-identity-extensions] or any other entity.

   No assertion is made about the veracity of the measurement data from
   sources other than the LIS.  A combination of tags MAY be included to
   indicate that measurement data from both sources was used.















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   For example, the first tuple of the following PIDF-LO indicates that
   measurement data from a LIS and a device was combined to produce the
   result, the second tuple was produced by the LIS alone.

     <presence xmlns="urn:ietf:params:xml:ns:pidf"
               xmlns:gp="urn:ietf:params:xml:ns:pidf:geopriv10"
               xmlns:gml="http://www.opengis.net/gml"
               xmlns:gs="http://www.opengis.net/pidflo/1.0"
               xmlns:lmsrc="urn:ietf:params:xml:ns:pidf:geopriv10:lmsrc"
               entity="pres:lm@example.com">
       <tuple id="deviceLoc">
         <status>
           <gp:geopriv>
             <gp:location-info>
               <gs:Circle srsName="urn:ogc:def:crs:EPSG::4326">
                 <gml:pos>7.34324 134.47162</gml:pos>
                 <gs:radius uom="urn:ogc:def:uom:EPSG::9001">
                   850.24
                 </gs:radius>
               </gs:Circle>
             </gp:location-info>
             <gp:usage-rules/>
             <gp:method>OTDOA</gp:method>
             <lmsrc:source>lis device</lmsrc:source>
           </gp:geopriv>
         </status>
       </tuple>
       <tuple id="lisLoc">
         <status>
           <gp:geopriv>
             <gp:location-info>
               <gs:Circle srsName="urn:ogc:def:crs:EPSG::4326">
                 <gml:pos>7.34379 134.46484</gml:pos>
                 <gs:radius uom="urn:ogc:def:uom:EPSG::9001">
                   9000
                 </gs:radius>
               </gs:Circle>
             </gp:location-info>
             <gp:usage-rules/>
             <gp:method>Cell</gp:method>
             <lmsrc:source>lis</lmsrc:source>
           </gp:geopriv>
         </status>
       </tuple>
     </presence>






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5.  Location-Related Measurement Data Types

   This document defines location-related measurement data types for a
   range of common network types.

5.1.  LLDP Measurements

   LLDP messages are sent between adjacent nodes in an IEEE 802 network
   (e.g. wired Ethernet, WiFi, 802.16).  These messages all contain
   identification information for the sending node, which can be used to
   determine location information.  A Device that receives LLDP messages
   can report this information as a location-related measurement to the
   LIS, which is then able to use the measurement data in determining
   the location of the Device.

   The Device MUST report the values directly as they were provided by
   the adjacent node.  Attempting to adjust or translate the type of
   identifier is likely to cause the measurement data to be useless.

   Where a Device has received LLDP messages from multiple adjacent
   nodes, it should provide information extracted from those messages by
   repeating the "lldp" element.

   An example of an LLDP measurement is shown in Figure 4.  This shows
   an adjacent node (chassis) that is identified by the IP address
   192.0.2.45 (hexadecimal c000022d) and the port on that node is
   numbered using an agent circuit ID [RFC3046] of 162 (hexadecimal a2).

     <measurements xmlns="urn:ietf:params:xml:ns:geopriv:lm"
                   time="2008-04-29T14:33:58">
       <lldp xmlns="urn:ietf:params:xml:ns:geopriv:lm:lldp">
         <chassis type="4">c000022d</chassis>
         <port type="6">a2</port>
       </lldp>
     </measurements>

                    Figure 4: LLDP Measurement Example

   IEEE 802 Devices that are able to obtain information about adjacent
   network switches and their attachment to them by other means MAY use
   this data type to convey this information.

5.2.  DHCP Relay Agent Information Measurements

   The DHCP Relay Agent Information option [RFC3046] provides
   measurement data about the network attachment of a Device.  This
   measurement data can be included in the "dhcp-rai" element.




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   The elements in the DHCP relay agent information options are opaque
   data types assigned by the DHCP relay agent.  The three items are all
   optional: circuit identifier ("circuit", [RFC3046]), remote
   identifier ("remote", [RFC3046], [RFC4649]) and subscriber identifier
   ("subscriber", [RFC3993], [RFC4580]).  The DHCPv6 remote identifier
   has an associated enterprise number [IANA.enterprise] as an XML
   attribute.

     <measurements xmlns="urn:ietf:params:xml:ns:geopriv:lm"
                   time="2008-04-29T14:33:58">
       <dhcp-rai xmlns="urn:ietf:params:xml:ns:geopriv:lm:dhcp">
         <giaddr>::ffff:192.0.2.158</giaddr>
         <circuit>108b</circuit>
       </dhcp-rai>
     </measurements>

        Figure 5: DHCP Relay Agent Information Measurement Example

   The "giaddr" is specified as a dotted quad IPv4 address or an RFC
   4291 [RFC4291] IPv6 address.  The enterprise number is specified as a
   decimal integer.  All other information is included verbatim from the
   DHCP request in hexadecimal format.

5.3.  802.11 WLAN Measurements

   In WiFi, or 802.11, networks a Device might be able to provide
   information about the wireless access point (WAP) that it is attached
   to, or other WiFi points it is able to see.  This is provided using
   the "wifi" element, as shown in Figure 6.






















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     <measurements xmlns="urn:ietf:params:xml:ns:geopriv:lm"
                   time="2008-04-29T14:33:58">
       <wifi xmlns="urn:ietf:params:xml:ns:geopriv:lm:wifi">
         <nicType>Example WiFi Device</nicType>
         <servingWap>
           <ssid>wlan-home</ssid>
           <bssid>00-12-F0-A0-80-EF</bssid>
           <channel>7</channel>
           <rssi>-55</rssi>
         </servingWap>
         <neighbourWap>
           <ssid>wlan-home</ssid>
           <bssid>00-12-F0-A0-80-F0</bssid>
           <rssi>-65</rssi>
         </neighbourWap>
         <neighbourWap>
           <ssid>vendordefault</ssid>
           <bssid>00-12-F0-A0-80-F1</bssid>
           <rssi>-68</rssi>
         </neighbourWap>
         <neighbourWap>
           <ssid>ironicname</ssid>
           <bssid>00-12-F0-A0-80-F2</bssid>
           <rssi>-75</rssi>
         </neighbourWap>
       </wifi>
     </measurements>

                 Figure 6: 802.11 WLAN Measurement Example

   A wifi element is made up of a serving WAP, zero or more neighbouring
   WAPs, and an optional "nicType" element.  Each WAP element is
   comprised of the following fields:

   ssid:  The service set identifier for the wireless network.  This
      parameter MAY be provided.

   bssid:  The basic service set identifier.  In an Infrastructure BSS
      network, the bssid is the 48 bit MAC address of the wireless
      access point, and it MUST be provided.

   wapname:  The broadcast name for the wireless access point.  This
      element is optional.

   location:  The location of the wireless access point, as reported
      using by the wireless access point.  This optional element
      contains GML geometry, following the restrictions described in
      [RFC5491].



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   type:  The network type for the network access.  This element
      includes the alphabetic suffix of the 802.11 specification that
      defines the radio interface; e.g. "a", "b", "g", or "n".  This
      element is optional.

   channel:  The channel number (frequency) that the wireless access
      point operates on.  This element is optional.

   rssi:  The received signal strength indicator of the WAP as seen by
      the wireless receiver.  This value SHOULD be in units of dBm (with
      RMS error in dB).  If the units are unknown, the "dBm" attribute
      MUST be set to "false".  Signal strength reporting on current
      hardware uses a range of different units; therefore, the value of
      the "nicType" element SHOULD be included if the units are not
      known to be in dBm and the value reported by the hardware should
      be included without modification.  This element is optional and
      includes optional "rmsError" and "samples" attributes.

   snr:  The signal to noise ratio measured by the Device, in dBm.  This
      element is optional and includes optional "rmsError" and "samples"
      attributes.

   rtt:  The total round trip time from the time that a request is sent
      by the Device to the time that it receives the response from the
      access point.  This measurement includes any delays that might
      occur between the time that the access point receives the message
      and the time that it sends the response.  If the delay at an
      access point is known, this value can be used to calculate an
      approximate distance between device and access point.  This
      element is optional and includes optional "rmsError" and "samples"
      attributes.

   The "nicType" element is used to specify the make and model of the
   wireless network interface in the Device.  Different 802.11 chipsets
   report the signal strength in different ways, so the network
   interface type must be specified in order for the LIS to use signal
   strength indicators as part of its location determination process.
   The content of this field is unconstrained and no mechanisms are
   specified to ensure uniqueness.

5.3.1.  Wifi Measurement Requests

   Two elements are defined for requesting WiFi measurements in a
   measurement request:







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   type:  The "type" element identifies the desired type (or types that
      are requested.

   parameter:  The "parameter" element identifies an optional
      measurements are requested for each measured access point.  An
      element is identified by its qualified name.

   Multiple types or parameters can be requested by repeating either
   element.

5.4.  Cellular Measurements

   Cellular Devices are common throughout the world and base station
   identifiers can provide a good source of coarse location information.
   This information can be provided to a LIS run by the cellar operator,
   or may be provided to an alternative LIS operator that has access to
   one of several global cell-id to location mapping databases.

   A number of advanced location determination methods have been
   developed for cellular networks.  For these methods a range of
   measurement parameters can be collected by the network, Device, or
   both in cooperation.  This document includes a basic identifier for
   the wireless transmitter only; future efforts might define additional
   parameters that enable more accurate methods of location
   determination.

   The cellular measurement set allows a Device to report to a LIS any
   LTE (Figure 7), UMTS (Figure 8), GSM (Figure 9) or CDMA (Figure 10)
   cells that it is able to observe.  Cells are reported using their
   global identifiers.  All 3GPP cells are identified by public land
   mobile network (PLMN), which is formed of mobile country code (MCC)
   and mobile network code (MNC); specific fields are added for each
   network type.  All other values are decimal integers.


















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     <measurements xmlns="urn:ietf:params:xml:ns:geopriv:lm"
                   time="2008-04-29T14:33:58">
       <cellular xmlns="urn:ietf:params:xml:ns:geopriv:lm:cell">
         <servingCell>
           <mcc>465</mcc><mnc>20</mnc>
           <eucid>80936424</eucid>
         </servingCell>
         <observedCell>
           <mcc>465</mcc><mnc>06</mnc>
           <eucid>10736789</eucid>
         </observedCell>
       </cellular>
     </measurements>

   Long term evolution (LTE) cells are identified by a 28-bit cell
   identifier (eucid).

                Figure 7: Example LTE Cellular Measurement


     <measurements xmlns="urn:ietf:params:xml:ns:geopriv:lm"
                   time="2008-04-29T14:33:58">
       <cellular xmlns="urn:ietf:params:xml:ns:geopriv:lm:cell">
         <servingCell>
           <mcc>465</mcc><mnc>20</mnc>
           <rnc>2000</rnc><cid>65000</cid>
         </servingCell>
         <observedCell>
           <mcc>465</mcc><mnc>06</mnc>
           <lac>16383</lac><cid>32767</cid>
         </observedCell>
       </cellular>
     </measurements>

   Universal mobile telephony service (UMTS) cells are identified by
   radio network controller (rnc) and cell id (cid).

                Figure 8: Example UMTS Cellular Measurement













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     <measurements xmlns="urn:ietf:params:xml:ns:geopriv:lm"
                   time="2008-04-29T14:33:58">
       <cellular xmlns="urn:ietf:params:xml:ns:geopriv:lm:cell">
         <servingCell>
           <mcc>465</mcc><mnc>06</mnc>
           <lac>16383</lac><cid>32767</cid>
         </servingCell>
       </cellular>
     </measurements>

   Groupe Spe'ciale Mobile (GSM) cells are identified by local radio
   network controller (rnc) and cell id (cid).

                Figure 9: Example GSM Cellular Measurement


     <measurements xmlns="urn:ietf:params:xml:ns:geopriv:lm"
                   time="2008-04-29T14:33:58">
       <cellular xmlns="urn:ietf:params:xml:ns:geopriv:lm:cell">
         <servingCell>
           <nid>4723</nid><sid>15892</sid><baseid>12</baseid>
         </servingCell>
         <observedCell>
           <nid>4723</nid><sid>15892</sid><baseid>13</baseid>
         </observedCell>
       </cellular>
     </measurements>

   Code division multiple access (CDMA) cells are not identified by
   PLMN, instead these use network id (nid), system id (sid) and base
   station id (baseid).

               Figure 10: Example CDMA Cellular Measurement

   In general a cellular Device will be attached to the cellular network
   and so the notion of a serving cell exists.  Cellular network also
   provide overlap between neighbouring sites, so a mobile Device can
   hear more than one cell.  The measurement schema supports sending
   both the serving cell and any other cells that the mobile might be
   able to hear.  In some cases, the Device may simply be listening to
   cell information without actually attaching to the network, mobiles
   without a SIM are an example of this.  In this case the Device may
   simply report cells it can hear without flagging one as a serving
   cell.  An example of this is shown in Figure 11.







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     <measurements xmlns="urn:ietf:params:xml:ns:geopriv:lm"
                   time="2008-04-29T14:33:58">
       <cellular xmlns="urn:ietf:params:xml:ns:geopriv:lm:cell">
         <observedCell>
           <mcc>465</mcc><mnc>20</mnc>
           <rnc>2000</rnc><cid>65000</cid>
         </observedCell>
         <observedCell>
           <mcc>465</mcc><mnc>06</mnc>
           <lac>16383</lac><cid>32767</cid>
         </observedCell>
       </cellular>
     </measurements>

             Figure 11: Example Observed Cellular Measurement

5.4.1.  Cellular Measurement Requests

   Two elements can be used in measurement requests for cellular
   measurements:

   type:  A label indicating the type of identifier to provide: one of
      "gsm", "umts", "lte", or "cdma".

   network:  The network portion of the cell identifier.  For 3GPP
      networks, this is the combination of MCC and MNC; for CDMA, this
      is the network identifier.

   Multiple identifier types or networks can be identified by repeating
   either element.

5.5.  GNSS Measurements

   GNSS use orbiting satellites to transmit signals.  A Device with a
   GNSS receiver is able to take measurements from the satellite
   signals.  The results of these measurements can be used to determine
   time and the location of the Device.

   Determining location and time in autonomous GNSS receivers follows
   three steps:

   Signal acquisition:  During the signal acquisition stage, the
      receiver searches for the repeating code that is sent by each GNSS
      satellite.  Successful operation typically requires measurement
      data for a minimum of 5 satellites.  At this stage, measurement
      data is available to the Device.





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   Navigation message decode:  Once the signal has been acquired, the
      receiver then receives information about the configuration of the
      satellite constellation.  This information is broadcast by each
      satellite and is modulated with the base signal at a low rate; for
      instance, GPS sends this information at about 50 bits per second.

   Calculation:  The measurement data is combined with the data on the
      satellite constellation to determine the location of the receiver
      and the current time.

   A Device that uses a GNSS receiver is able to report measurements
   after the first stage of this process.  A LIS can use the results of
   these measurements to determine a location.  In the case where there
   are fewer results available than the optimal minimum, the LIS might
   be able to use other sources of measurement information and combine
   these with the available measurement data to determine a position.

      Note: The use of different sets of GNSS _assistance data_ can
      reduce the amount of time required for the signal acquisition
      stage and obviate the need for the receiver to extract data on the
      satellite constellation.  Provision of assistance data is outside
      the scope of this document.

   Figure 12 shows an example of GNSS measurement data.  The measurement
   shown is for the GPS system and includes measurement data for three
   satellites only.

























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     <measurements xmlns="urn:ietf:params:xml:ns:geopriv:lm"
                   time="2008-04-29T14:33:58" timeError="2e-5">
       <gnss xmlns="urn:ietf:params:xml:ns:geopriv:lm:gnss"
             system="gps" signal="L1">
         <sat num="19">
           <doppler>499.9395</doppler>
           <codephase rmsError="1.6e-9">0.87595747</codephase>
           <cn0>45</cn0>
         </sat>
         <sat num="27">
           <doppler>378.2657</doppler>
           <codephase rmsError="1.6e-9">0.56639479</codephase>
           <cn0>52</cn0>
         </sat>
         <sat num="20">
           <doppler>-633.0309</doppler>
           <codephase rmsError="1.6e-9">0.57016835</codephase>
           <cn0>48</cn0>
         </sat>
       </gnss>
     </measurements>

                    Figure 12: Example GNSS Measurement

   Each "gnss" element represents a single set of GNSS measurement data,
   taken at a single point in time.  Measurements taken at different
   times can be included in different "gnss" elements to enable
   iterative refinement of results.

   GNSS measurement parameters are described in more detail in the
   following sections.

5.5.1.  GNSS System and Signal

   The GNSS measurement structure is designed to be generic and to apply
   to different GNSS types.  Different signals within those systems are
   also accounted for and can be measured separately.

   The GNSS type determines the time system that is used.  An indication
   of the type of system and signal can ensure that the LIS is able to
   correctly use measurements.

   Measurements for multiple GNSS types and signals can be included by
   repeating the "gnss" element.

   This document creates an IANA registry for GNSS types.  Two satellite
   systems are registered by this document: GPS and Galileo.  Details
   for the registry are included in Section 9.1.



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5.5.2.  Time

   Each set of GNSS measurements is taken at a specific point in time.
   The "time" attribute is used to indicate the time that the
   measurement was acquired, if the receiver knows how the time system
   used by the GNSS relates to UTC time.

   Alternative to (or in addition to) the measurement time, the
   "gnssTime" element MAY be included.  The "gnssTime" element includes
   a relative time in milliseconds using the time system native to the
   satellite system.  For the GPS satellite system, the "gnssTime"
   element includes the time of week in milliseconds.  For the Galileo
   system, the "gnssTime" element includes the time of day in
   milliseconds.

   The accuracy of the time measurement provided is critical in
   determining the accuracy of the location information derived from
   GNSS measurements.  The receiver SHOULD indicate an estimated time
   error for any time that is provided.  An RMS error can be included
   for the "gnssTime" element, with a value in milliseconds.

5.5.3.  Per-Satellite Measurement Data

   Multiple satellites are included in each set of GNSS measurements
   using the "sat" element.  Each satellite is identified by a number in
   the "num" attribute.  The satellite number is consistent with the
   identifier used in the given GNSS.

   Both the GPS and Galileo systems use satellite numbers between 1 and
   64.

   The GNSS receiver measures the following parameters for each
   satellite:

   doppler:  The observed Doppler shift of the satellite signal,
      measured in meters per second.  This is converted from a value in
      Hertz by the receiver to allow the measurement to be used without
      knowledge of the carrier frequency of the satellite system.  This
      value includes an optional RMS error attribute, also measured in
      meters per second.

   codephase:  The observed code phase for the satellite signal,
      measured in milliseconds.  This is converted from a value in chips
      or wavelengths.  Increasing values indicate increasing
      pseudoranges.  This value includes an optional RMS error
      attribute, also measured in milliseconds.





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   cn0:  The signal to noise ratio for the satellite signal, measured in
      decibel-Hertz (dB-Hz).  The expected range is between 20 and 50
      dB-Hz.

   mp:  An estimation of the amount of error that multipath signals
      contribute in metres.  This parameter is optional.

   cq:  An indication of the carrier quality.  Two attributes are
      included: "continuous" may be either "true" or "false"; direct may
      be either "direct" or "inverted".  This parameter is optional.

   adr:  The accumulated Doppler range, measured in metres.  This
      parameter is optional and is not necessary unless multiple sets of
      GNSS measurements are provided.

   All values are converted from measures native to the satellite system
   to generic measures to ensure consistency of interpretation.  Unless
   necessary, the schema does not constrain these values.

5.5.4.  GNSS Measurement Requests

   Measurement requests can include a "gnss" element, which includes the
   "system" and "signal" attributes.  Multiple elements can be included
   to indicate a requests for GNSS measurements from multiple systems or
   signals.

5.6.  DSL Measurements

   Digital Subscriber Line (DSL) networks rely on a range of network
   technology.  DSL deployments regularly require cooperation between
   multiple organizations.  These fall into two broad categories:
   infrastructure providers and Internet service providers (ISPs).
   Infrastructure providers manage the bulk of the physical
   infrastructure including cabling.  End users obtain their service
   from an ISP, which manages all aspects visible to the end user
   including IP address allocation and operation of a LIS.  See
   [DSL.TR025] and [DSL.TR101] for further information on DSL network
   deployments.

   Exchange of measurement information between these organizations is
   necessary for location information to be correctly generated.  The
   ISP LIS needs to acquire location information from the infrastructure
   provider.  However, the infrastructure provider has no knowledge of
   Device identifiers, it can only identify a stream of data that is
   sent to the ISP.  This is resolved by passing measurement data
   relating to the Device to a LIS operated by the infrastructure
   provider.




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5.6.1.  L2TP Measurements

   Layer 2 Tunneling Protocol (L2TP) is a common means of linking the
   infrastructure provider and the ISP.  The infrastructure provider LIS
   requires measurement data that identifies a single L2TP tunnel, from
   which it can generate location information.  Figure 13 shows an
   example L2TP measurement.

     <measurements xmlns="urn:ietf:params:xml:ns:geopriv:lm"
                   time="2008-04-29T14:33:58">
       <dsl xmlns="urn:ietf:params:xml:ns:geopriv:lm:dsl">
         <l2tp>
           <src>192.0.2.10</src>
           <dest>192.0.2.61</dest>
           <session>528</session>
         </l2tp>
       </dsl>
     </measurements>

                  Figure 13: Example DSL L2TP Measurement

5.6.2.  RADIUS Measurements

   When authenticating network access, the infrastructure provider might
   employ a RADIUS [RFC2865] proxy at the DSL Access Module (DSLAM) or
   Access Node (AN).  These messages provide the ISP RADIUS server with
   an identifier for the DSLAM or AN, plus the slot and port that the
   Device is attached on.  These data can be provided as a measurement,
   which allows the infrastructure provider LIS to generate location
   information.

   The format of the AN, slot and port identifiers are not defined in
   the RADIUS protocol.  Slot and port together identify a circuit on
   the AN, analogous to the circuit identifier in [RFC3046].  These
   items are provided directly, as they were in the RADIUS message.  An
   example is shown in Figure 14.

     <measurements xmlns="urn:ietf:params:xml:ns:geopriv:lm"
                   time="2008-04-29T14:33:58">
       <dsl xmlns="urn:ietf:params:xml:ns:geopriv:lm:dsl">
         <an>AN-7692</an>
         <slot>3</slot>
         <port>06</port>
       </dsl>
     </measurements>

                 Figure 14: Example DSL RADIUS Measurement




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5.6.3.  Ethernet VLAN Tag Measurements

   For Ethernet-based DSL access networks, the DSL Access Module (DSLAM)
   or Access Node (AN) provide two VLAN tags on packets.  A C-TAG is
   used to identify the incoming residential circuit, while the S-TAG is
   used to identify the DSLAM or AN.  The C-TAG and S-TAG together can
   be used to identify a single point of network attachment.  An example
   is shown in Figure 15.

     <measurements xmlns="urn:ietf:params:xml:ns:geopriv:lm"
                   time="2008-04-29T14:33:58">
       <dsl xmlns="urn:ietf:params:xml:ns:geopriv:lm:dsl">
         <stag>613</stag>
         <ctag>1097</ctag>
       </dsl>
     </measurements>

                Figure 15: Example DSL VLAN Tag Measurement

   Alternatively, the C-TAG can be replaced by data on the slot and port
   that the Device is attached to.  This information might be included
   in RADIUS requests that are proxied from the infrastructure provider
   to the ISP RADIUS server.

5.6.4.  ATM Virtual Circuit Measurements

   An ATM virtual circuit can be employed between the ISP and
   infrastructure provider.  Providing the virtual port ID (VPI) and
   virtual circuit ID (VCI) for the virtual circuit gives the
   infrastructure provider LIS the ability to identify a single data
   stream.  A sample measurement is shown in Figure 16.

     <measurements xmlns="urn:ietf:params:xml:ns:geopriv:lm"
                   time="2008-04-29T14:33:58">
       <dsl xmlns="urn:ietf:params:xml:ns:geopriv:lm:dsl">
         <vpi>55</vpi>
         <vci>6323</vci>
       </dsl>
     </measurements>

                  Figure 16: Example DSL ATM Measurement


6.  Measurement Schemas

   The schema are broken up into their respective functions.  There is a
   base container schema into which all measurements are placed, plus
   definitions for a measurement request (Section 6.1).  A PIDF-LO



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   extension is defined in a separate schema (Section 6.2).  There is a
   basic types schema, that contains various base type definitions for
   things such as the "rmsError" and "samples" attributes IPv4, IPv6 and
   MAC addresses (Section 6.3).  Then each of the specific measurement
   types is defined in its own schema.

6.1.  Measurement Container Schema

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

    <xs:annotation>
      <xs:appinfo
          source="urn:ietf:params:xml:schema:geopriv:lm">
      </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 location measurements.
      </xs:documentation>
    </xs:annotation>

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

    <xs:element name="measurements">
      <xs:complexType>
        <xs:complexContent>
          <xs:restriction base="xs:anyType">
            <xs:sequence>
              <xs:any namespace="##other" processContents="lax"
                      minOccurs="0" maxOccurs="unbounded"/>
            </xs:sequence>
            <xs:attribute name="time" type="xs:dateTime"/>
            <xs:attribute name="timeError" type="bt:positiveDouble"/>
            <xs:attribute name="expires" type="xs:dateTime"/>
            <xs:anyAttribute namespace="##any" processContents="lax"/>
          </xs:restriction>
        </xs:complexContent>
      </xs:complexType>
    </xs:element>

    <xs:element name="measurementRequest"



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                type="lm:measurementRequestType"/>
    <xs:complexType name="measurementRequestType">
      <xs:complexContent>
        <xs:restriction base="xs:anyType">
          <xs:sequence>
            <xs:element name="measurement" type="lm:measurementType"
                        minOccurs="0" maxOccurs="unbounded"/>
            <xs:any namespace="##other" processContents="lax"
                    minOccurs="0" maxOccurs="unbounded"/>
          </xs:sequence>
        </xs:restriction>
      </xs:complexContent>
    </xs:complexType>

    <xs:complexType name="measurementType">
      <xs:complexContent>
        <xs:restriction base="xs:anyType">
          <xs:sequence>
            <xs:any namespace="##other" processContents="lax"
                    minOccurs="0" maxOccurs="unbounded"/>
          </xs:sequence>
          <xs:attribute name="type" type="xs:QName" use="required"/>
          <xs:attribute name="samples" type="xs:positiveInteger"/>
        </xs:restriction>
      </xs:complexContent>
    </xs:complexType>

                       Measurement Container Schema























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6.2.  Measurement Source Schema

   <?xml version="1.0"?>
   <xs:schema
       xmlns:lmsrc="urn:ietf:params:xml:ns:pidf:geopriv10:lmsrc"
       xmlns:xs="http://www.w3.org/2001/XMLSchema"
       targetNamespace="urn:ietf:params:xml:ns:pidf:geopriv10:lmsrc"
       elementFormDefault="qualified"
       attributeFormDefault="unqualified">

     <xs:annotation>
       <xs:appinfo
           source="urn:ietf:params:xml:schema:pidf:geopriv10:lmsrc">
       </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 an extension to PIDF-LO that indicates the
         type of source that produced the measurement data used in
         generating the associated location information.
       </xs:documentation>
     </xs:annotation>

     <xs:element name="source" type="lmsrc:sourceType"/>
     <xs:simpleType name="sourceType">
       <xs:list>
         <xs:simpleType>
           <xs:restriction base="xs:token">
             <xs:enumeration value="lis"/>
             <xs:enumeration value="device"/>
             <xs:enumeration value="other"/>
           </xs:restriction>
         </xs:simpleType>
       </xs:list>
     </xs:simpleType>
   </xs:schema>

                Measurement Source PIDF-LO Extension Schema

6.3.  Base Type Schema

   Note that the pattern rules in the following schema wrap due to
   length constraints.  None of the patterns contain whitespace.

 <?xml version="1.0"?>
 <xs:schema
   xmlns:bt="urn:ietf:params:xml:ns:geopriv:lm:basetypes"
   xmlns:xs="http://www.w3.org/2001/XMLSchema"



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   targetNamespace="urn:ietf:params:xml:ns:geopriv:lm:basetypes"
   elementFormDefault="qualified"
   attributeFormDefault="unqualified">

   <xs:annotation>
     <xs:appinfo
         source="urn:ietf:params:xml:schema:geopriv:lm:basetypes">
     </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 set of base type elements.
     </xs:documentation>
   </xs:annotation>

   <xs:simpleType name="byteType">
     <xs:restriction base="xs:integer">
       <xs:minInclusive value="0"/>
       <xs:maxInclusive value="255"/>
     </xs:restriction>
   </xs:simpleType>
   <xs:simpleType name="twoByteType">
     <xs:restriction base="xs:integer">
       <xs:minInclusive value="0"/>
       <xs:maxInclusive value="65535"/>
     </xs:restriction>
   </xs:simpleType>

   <xs:simpleType name="nonNegativeDouble">
     <xs:restriction base="xs:double">
       <xs:minInclusive value="0.0"/>
     </xs:restriction>
   </xs:simpleType>
   <xs:simpleType name="positiveDouble">
     <xs:restriction base="bt:nonNegativeDouble">
       <xs:minExclusive value="0.0"/>
     </xs:restriction>
   </xs:simpleType>

   <xs:complexType name="doubleWithRMSError">
     <xs:simpleContent>
       <xs:extension base="xs:double">
         <xs:attribute name="rmsError" type="bt:positiveDouble"/>
         <xs:attribute name="samples" type="xs:positiveInteger"/>
       </xs:extension>
     </xs:simpleContent>
   </xs:complexType>
   <xs:complexType name="nnDoubleWithRMSError">



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     <xs:simpleContent>
       <xs:restriction base="bt:doubleWithRMSError">
         <xs:minInclusive value="0"/>
       </xs:restriction>
     </xs:simpleContent>
   </xs:complexType>

   <xs:simpleType name="ipAddressType">
     <xs:union memberTypes="bt:IPv6AddressType bt:IPv4AddressType"/>
   </xs:simpleType>

   <!-- IPv6 format definition -->
   <xs:simpleType name="IPv6AddressType">
     <xs:annotation>
       <xs:documentation>
         An IP version 6 address, based on RFC 4291.
       </xs:documentation>
     </xs:annotation>
     <xs:restriction base="xs:token">
       <!-- Fully specified address -->
       <xs:pattern value="[0-9A-Fa-f]{1,4}(:[0-9A-Fa-f]{1,4}){7}"/>
       <!-- Double colon start -->
       <xs:pattern value=":(:[0-9A-Fa-f]{1,4}){1,7}"/>
       <!-- Double colon middle -->
       <xs:pattern value="([0-9A-Fa-f]{1,4}:){1,6}
                          (:[0-9A-Fa-f]{1,4}){1}"/>
       <xs:pattern value="([0-9A-Fa-f]{1,4}:){1,5}
                          (:[0-9A-Fa-f]{1,4}){1,2}"/>
       <xs:pattern value="([0-9A-Fa-f]{1,4}:){1,4}
                          (:[0-9A-Fa-f]{1,4}){1,3}"/>
       <xs:pattern value="([0-9A-Fa-f]{1,4}:){1,3}
                          (:[0-9A-Fa-f]{1,4}){1,4}"/>
       <xs:pattern value="([0-9A-Fa-f]{1,4}:){1,2}
                          (:[0-9A-Fa-f]{1,4}){1,5}"/>
       <xs:pattern value="([0-9A-Fa-f]{1,4}:){1}
                          (:[0-9A-Fa-f]{1,4}){1,6}"/>
       <!-- Double colon end -->
       <xs:pattern value="([0-9A-Fa-f]{1,4}:){1,7}:"/>
       <!-- IPv4-Compatible and IPv4-Mapped Addresses -->
       <xs:pattern value="((:(:0{1,4}){0,3}:[fF]{4})|(0{1,4}:
                          (:0{1,4}){0,2}:[fF]{4})|((0{1,4}:){2}
                          (:0{1,4})?:[fF]{4})|((0{1,4}:){3}:[fF]{4})
                          |((0{1,4}:){4}[fF]{4})):(25[0-5]|2[0-4][0-9]|
                          [0-1]?[0-9]?[0-9])\.(25[0-5]|2[0-4][0-9]|[0-1]
                          ?[0-9]?[0-9])\.(25[0-5]|2[0-4][0-9]|[0-1]?
                          [0-9]?[0-9])\.(25[0-5]|2[0-4][0-9]|[0-1]?
                          [0-9]?[0-9])"/>
       <!-- The unspecified address -->



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       <xs:pattern value="::"/>
     </xs:restriction>
   </xs:simpleType>

   <!-- IPv4 format definition -->
   <xs:simpleType name="IPv4AddressType">
     <xs:restriction base="xs:token">
       <xs:pattern value="(25[0-5]|2[0-4][0-9]|[0-1]?[0-9]?[0-9])\.
                          (25[0-5]|2[0-4][0-9]|[0-1]?[0-9]?[0-9])\.
                          (25[0-5]|2[0-4][0-9]|[0-1]?[0-9]?[0-9])\.
                          (25[0-5]|2[0-4][0-9]|[0-1]?[0-9]?[0-9])"/>
     </xs:restriction>
   </xs:simpleType>

   <!-- IEEE specifies a MAC address as having a -
        between 2 hex digit pairs -->
   <xs:simpleType name="macAddressType">
     <xs:restriction base="xs:token">
       <xs:pattern value="([0-9A-Fa-f]{2}-){5}([0-9A-Fa-f]{2})"/>
     </xs:restriction>
   </xs:simpleType>

 </xs:schema>

                             Base Type Schema

6.4.  LLDP Measurement Schema

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

    <xs:annotation>
      <xs:appinfo
          source="urn:ietf:params:xml:schema:geopriv:lm:lldp">
      </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 set of LLDP location measurements.
      </xs:documentation>
    </xs:annotation>




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

    <xs:element name="lldp" type="lldp:lldpMeasurementType"/>
    <xs:complexType name="lldpMeasurementType">
      <xs:complexContent>
        <xs:restriction base="xs:anyType">
          <xs:sequence>
            <xs:element name="chassis" type="lldp:lldpDataType"/>
            <xs:element name="port" type="lldp:lldpDataType"/>
            <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:complexType name="lldpDataType">
      <xs:simpleContent>
        <xs:extension base="lldp:lldpOctetStringType">
          <xs:attribute name="type" type="bt:byteType"
                        use="required"/>
        </xs:extension>
      </xs:simpleContent>
    </xs:complexType>

    <xs:simpleType name="lldpOctetStringType">
      <xs:restriction base="xs:hexBinary">
        <xs:minLength value="1"/>
        <xs:maxLength value="255"/>
      </xs:restriction>
    </xs:simpleType>

  </xs:schema>

                          LLDP measurement schema

6.5.  DHCP Measurement Schema

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




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    <xs:annotation>
      <xs:appinfo
          source="urn:ietf:params:xml:schema:geopriv:lm:dhcp">
      </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 set of DHCP location measurements.
      </xs:documentation>
    </xs:annotation>

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

    <!-- DHCP Relay Agent Information Option -->
    <xs:element name="dhcp-rai" type="dhcp:dhcpType"/>
    <xs:complexType name="dhcpType">
      <xs:complexContent>
        <xs:restriction base="xs:anyType">
          <xs:sequence>
            <xs:element name="giaddr" type="bt:ipAddressType"/>
            <xs:element name="circuit"
                        type="xs:hexBinary" minOccurs="0"/>
            <xs:element name="remote"
                        type="dhcp:dhcpRemoteType" minOccurs="0"/>
            <xs:element name="subscriber"
                        type="xs:hexBinary" minOccurs="0"/>
            <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:complexType name="dhcpRemoteType">
      <xs:simpleContent>
        <xs:extension base="xs:hexBinary">
          <xs:attribute name="enterprise" type="xs:positiveInteger"
                        use="optional"/>
        </xs:extension>
      </xs:simpleContent>
    </xs:complexType>

  </xs:schema>

                          DHCP measurement schema

6.6.  WiFi Measurement Schema



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  <?xml version="1.0"?>
  <xs:schema
      xmlns:wifi="urn:ietf:params:xml:ns:geopriv:lm:wifi"
      xmlns:bt="urn:ietf:params:xml:ns:geopriv:lm:basetypes"
      xmlns:gml="http://www.opengis.net/gml"
      xmlns:xs="http://www.w3.org/2001/XMLSchema"
      targetNamespace="urn:ietf:params:xml:ns:geopriv:lm:wifi"
      elementFormDefault="qualified"
      attributeFormDefault="unqualified">

    <xs:annotation>
      <xs:appinfo
          source="urn:ietf:params:xml:schema:geopriv:lm:wifi">
        WiFi location measurements
      </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 basic set of WiFi location measurements.
      </xs:documentation>
    </xs:annotation>

    <xs:import namespace="urn:ietf:params:xml:ns:geopriv:lm:basetypes"/>
    <xs:import namespace="http://www.opengis.net/gml"/>

    <xs:element name="wifi" type="wifi:wifiNetworkType"/>

    <xs:complexType name="wifiNetworkType">
      <xs:complexContent>
        <xs:restriction base="xs:anyType">
          <xs:sequence>
            <xs:element name="nicType" type="xs:token"
                        minOccurs="0"/>
            <xs:choice>
              <xs:element name="servingWap" type="wifi:wifiType"/>
              <xs:element name="neighbourWap" type="wifi:wifiType"/>
            </xs:choice>
            <xs:element name="neighbourWap" type="wifi:wifiType"
                        minOccurs="0" maxOccurs="unbounded"/>
          </xs:sequence>
          <xs:anyAttribute namespace="##any" processContents="lax"/>
        </xs:restriction>
      </xs:complexContent>
    </xs:complexType>

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



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          <xs:sequence>
            <xs:element name="ssid" type="wifi:ssidBaseType"
                        minOccurs="0"/>
            <xs:element name="bssid" type="bt:macAddressType"/>
            <xs:element name="wapname" type="wifi:ssidBaseType"
                        minOccurs="0"/>
            <xs:element name="location" minOccurs="0"
                        type="gml:GeometryPropertyType"/>
            <xs:element name="type" type="wifi:networkType"
                        minOccurs="0"/>
            <xs:element name="channel" type="xs:nonNegativeInteger"
                        minOccurs="0"/>
            <xs:element name="rssi" type="wifi:rssiType"
                        minOccurs="0"/>
            <xs:element name="snr" type="bt:doubleWithRMSError"
                        minOccurs="0"/>
            <xs:element name="rtt" type="bt:doubleWithRMSError"
                        minOccurs="0"/>
            <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:simpleType name="ssidBaseType">
      <xs:restriction base="xs:token">
        <xs:maxLength value="32"/>
      </xs:restriction>
    </xs:simpleType>

    <xs:simpleType name="networkType">
      <xs:restriction base="xs:token">
        <xs:pattern value="[a-zA-Z]+"/>
      </xs:restriction>
    </xs:simpleType>

    <xs:complexType name="rssiType">
      <xs:simpleContent>
        <xs:extension base="bt:doubleWithRMSError">
          <xs:attribute name="dBm" type="xs:boolean" default="true"/>
        </xs:extension>
      </xs:simpleContent>
    </xs:complexType>

    <!-- Measurement Request elements -->
    <xs:element name="type" type="wifi:networkType"/>



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    <xs:element name="parameter" type="xs:QName"/>

  </xs:schema>

                          WiFi measurement schema

6.7.  Cellular Measurement Schema

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

     <xs:annotation>
       <xs:appinfo
           source="urn:ietf:params:xml:schema:geopriv:lm:cell">
       </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 set of cellular location measurements.
       </xs:documentation>
     </xs:annotation>

     <xs:element name="cellular" type="cell:cellularType"/>

     <xs:complexType name="cellularType">
       <xs:complexContent>
         <xs:restriction base="xs:anyType">
           <xs:sequence>
             <xs:choice>
               <xs:element name="servingCell" type="cell:cellType"/>
               <xs:element name="observedCell" type="cell:cellType"/>
             </xs:choice>
             <xs:element name="observedCell" type="cell:cellType"
                         minOccurs="0" maxOccurs="unbounded"/>
           </xs:sequence>
           <xs:anyAttribute namespace="##any" processContents="lax"/>
         </xs:restriction>
       </xs:complexContent>
     </xs:complexType>

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



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           <xs:choice>
             <xs:sequence>
               <xs:element name="mcc" type="cell:mccType"/>
               <xs:element name="mnc" type="cell:mncType"/>
               <xs:choice>
                 <xs:sequence>
                   <xs:choice>
                     <xs:element name="rnc" type="cell:cellIdType"/>
                     <xs:element name="lac" type="cell:cellIdType"/>
                   </xs:choice>
                   <xs:element name="cid" type="cell:cellIdType"/>
                 </xs:sequence>
                 <xs:element name="eucid" type="cell:cellIdType"/>
               </xs:choice>
               <xs:any namespace="##other" processContents="lax"
                       minOccurs="0" maxOccurs="unbounded"/>
             </xs:sequence>
             <xs:sequence>
               <xs:element name="nid" type="cell:cellIdType"/>
               <xs:element name="sid" type="cell:cellIdType"/>
               <xs:element name="baseid" type="cell:cellIdType"/>
               <xs:any namespace="##other" processContents="lax"
                       minOccurs="0" maxOccurs="unbounded"/>
             </xs:sequence>
             <xs:any namespace="##other" processContents="lax"
                     minOccurs="0" maxOccurs="unbounded"/>
           </xs:choice>
         </xs:restriction>
       </xs:complexContent>
     </xs:complexType>

     <xs:simpleType name="mccType">
       <xs:restriction base="xs:token">
         <xs:pattern value="[0-9]{3}"/>
       </xs:restriction>
     </xs:simpleType>

     <xs:simpleType name="mncType">
       <xs:restriction base="xs:token">
         <xs:pattern value="[0-9]{2,3}"/>
       </xs:restriction>
     </xs:simpleType>

     <xs:simpleType name="cellIdType">
       <xs:restriction base="xs:nonNegativeInteger">
         <xs:maxInclusive value="268435456"/> <!-- 2^28 (eucid) -->
       </xs:restriction>
     </xs:simpleType>



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     <!-- Measurement Request elements -->

     <xs:element name="type" type="cell:typeType"/>
     <xs:simpleType name="typeType">
       <xs:restriction base="xs:token">
         <xs:enumeration value="gsm"/>
         <xs:enumeration value="umts"/>
         <xs:enumeration value="lte"/>
         <xs:enumeration value="cdma"/>
       </xs:restriction>
     </xs:simpleType>

     <xs:element name="network" type="cell:networkType"/>
     <xs:complexType name="networkType">
       <xs:complexContent>
         <xs:restriction base="xs:anyType">
           <xs:choice>
             <xs:sequence>
               <xs:element name="mcc" type="cell:mccType"/>
               <xs:element name="mnc" type="cell:mncType"/>
             </xs:sequence>
             <xs:element name="nid" type="cell:cellIdType"/>
           </xs:choice>
         </xs:restriction>
       </xs:complexContent>
     </xs:complexType>

   </xs:schema>

                        Cellular measurement schema

6.8.  GNSS Measurement Schema

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

   <xs:annotation>
     <xs:appinfo
         source="urn:ietf:params:xml:schema:geopriv:lm:gnss">
     </xs:appinfo>
     <xs:documentation source="http://www.ietf.org/rfc/rfcXXXX.txt">
       <!-- [[NOTE TO RFC-EDITOR: Please replace above URL with URL of



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            published RFC and remove this note.]] -->
       This schema defines a set of GNSS location measurements
     </xs:documentation>
   </xs:annotation>

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

   <!-- GNSS -->
   <xs:element name="gnss" type="gnss:gnssMeasurementType">
     <xs:unique name="gnssSatellite">
       <xs:selector xpath="sat"/>
       <xs:field xpath="@num"/>
     </xs:unique>
   </xs:element>

   <xs:complexType name="gnssMeasurementType">
     <xs:complexContent>
       <xs:restriction base="xs:anyType">
         <xs:sequence>
           <xs:element name="gnssTime" type="bt:nnDoubleWithRMSError"
                       minOccurs="0"/>
           <xs:element name="sat" type="gnss:gnssSatelliteType"
                       minOccurs="1" maxOccurs="64"/>
           <xs:any namespace="##other" processContents="lax"
                   minOccurs="0" maxOccurs="unbounded"/>
         </xs:sequence>
         <xs:attribute name="system" type="xs:token" use="required"/>
         <xs:attribute name="signal" type="xs:token"/>
         <xs:anyAttribute namespace="##any" processContents="lax"/>
       </xs:restriction>
     </xs:complexContent>
   </xs:complexType>

   <xs:complexType name="gnssSatelliteType">
     <xs:complexContent>
       <xs:restriction base="xs:anyType">
         <xs:sequence>
           <xs:element name="doppler" type="bt:doubleWithRMSError"/>
           <xs:element name="codephase" type="bt:nnDoubleWithRMSError"/>
           <xs:element name="cn0" type="bt:nonNegativeDouble"/>
           <xs:element name="mp" type="bt:positiveDouble"
                       minOccurs="0"/>
           <xs:element name="cq" type="gnss:codePhaseQualityType"
                       minOccurs="0"/>
           <xs:element name="adr" type="xs:double" minOccurs="0"/>
         </xs:sequence>
         <xs:attribute name="num" type="xs:positiveInteger"
                       use="required"/>



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       </xs:restriction>
     </xs:complexContent>
   </xs:complexType>

   <xs:complexType name="codePhaseQualityType">
     <xs:complexContent>
       <xs:restriction base="xs:anyType">
         <xs:attribute name="continuous" type="xs:boolean"
                       default="true"/>
         <xs:attribute name="direct" use="required">
           <xs:simpleType>
             <xs:restriction base="xs:token">
               <xs:enumeration value="direct"/>
               <xs:enumeration value="inverted"/>
             </xs:restriction>
           </xs:simpleType>
         </xs:attribute>
       </xs:restriction>
     </xs:complexContent>
   </xs:complexType>
 </xs:schema>

                          GNSS measurement Schema

6.9.  DSL Measurement Schema

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

    <xs:annotation>
      <xs:appinfo
          source="urn:ietf:params:xml:schema:geopriv:lm:dsl">
        DSL measurement definitions
      </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 basic set of DSL location measurements.
      </xs:documentation>
    </xs:annotation>

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



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    <xs:element name="dsl" type="dsl:dslVlanType"/>
    <xs:complexType name="dslVlanType">
      <xs:complexContent>
        <xs:restriction base="xs:anyType">
          <xs:choice>
            <xs:element name="l2tp">
              <xs:complexType>
                <xs:complexContent>
                  <xs:restriction base="xs:anyType">
                    <xs:sequence>
                      <xs:element name="src" type="bt:ipAddressType"/>
                      <xs:element name="dest" type="bt:ipAddressType"/>
                      <xs:element name="session"
                                  type="xs:nonNegativeInteger"/>
                    </xs:sequence>
                  </xs:restriction>
                </xs:complexContent>
              </xs:complexType>
            </xs:element>
            <xs:sequence>
              <xs:element name="an" type="xs:token"/>
              <xs:group ref="dsl:dslSlotPort"/>
            </xs:sequence>
            <xs:sequence>
              <xs:element name="stag" type="dsl:vlanIDType"/>
              <xs:choice>
                <xs:sequence>
                  <xs:element name="ctag" type="dsl:vlanIDType"/>
                  <xs:group ref="dsl:dslSlotPort" minOccurs="0"/>
                </xs:sequence>
                <xs:group ref="dsl:dslSlotPort"/>
              </xs:choice>
            </xs:sequence>
            <xs:sequence>
              <xs:element name="vpi" type="bt:byteType"/>
              <xs:element name="vci" type="bt:twoByteType"/>
            </xs:sequence>
            <xs:any namespace="##other" processContents="lax"
                    minOccurs="0" maxOccurs="unbounded"/>
          </xs:choice>
          <xs:anyAttribute namespace="##other" processContents="lax"/>
        </xs:restriction>
      </xs:complexContent>
    </xs:complexType>
    <xs:simpleType name="vlanIDType">
      <xs:restriction base="xs:nonNegativeInteger">
        <xs:maxInclusive value="4095"/>
      </xs:restriction>



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    </xs:simpleType>
    <xs:group name="dslSlotPort">
      <xs:sequence>
        <xs:element name="slot" type="xs:token"/>
        <xs:element name="port" type="xs:token"/>
      </xs:sequence>
    </xs:group>

  </xs:schema>

                          DSL measurement schema


7.  Privacy Considerations

   Location-related measurement data can be as privacy sensitive as
   location information.

   Measurement data is effectively equivalent to location information if
   the contextual knowledge necessary to generate one from the other is
   readily accessible.  Even where contextual knowledge is difficult to
   acquire, there can be no assurance that an authorized recipient of
   the contextual knowledge is also authorized to receive location
   information.

   In order to protect the privacy of the subject of location-related
   measurement data, this implies that measurement data is protected
   with the same degree of protection as location information.

7.1.  Measurement Data Privacy Model

   It is less desirable to distribute measurement data in the same
   fashion as location information.  Measurement data is less useful to
   location recipients than location information.  Therefore, a simple
   distribution model is desirable.

   In this simple model, the Device is the only entity that is able to
   distribute measurement data.  To use an analogy from the GEOPRIV
   architecture, the Device - as the Location Generator (or the
   Measurement Data Generator) - is the sole entity that can assume the
   roles of Rule Maker and Location Server.

   No entity can redistribute measurement data.  The Device directs
   other entities in how measurement data is used and retained.







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7.2.  LIS Privacy Requirements

   A LIS MUST NOT reveal location-related measurement data or location
   information based on measurement data to any other entity unless
   directed to do so by the Device.

   By adding measurement data to a request for location information, the
   Device implicitly grants permission for the LIS to generate the
   requested location information using the measurement data.
   Permission to use this data for any other purpose is not implied.

   As long as measurement data is only used in serving the request that
   contains it, rules regarding data retention are not necessary.  A LIS
   MUST discard location-related measurement data after servicing a
   request, unless the Device grants permission to use that information
   for other purposes.

7.3.  Measurement Data and Location URIs

   A LIS MAY use measurement data provided by the Device to serve
   requests to location URIs, if the Device permits it.  A Device
   permits this by including measurement data in a request that
   explcitly requests a location URI.  By requesting a location URI, the
   Device grants permission for the LIS to use the measurement data in
   serving requests to that URI.

   Note:  In HELD, the "any" type is not an explicit request for a
      location URI, though a location URI might be provided.

   The usefulness of measurement data that is provided in this fashion
   is limited.  The measurement data is only valid at the time that it
   was acquired by the Device.  At the time that a request is made to a
   location URI, the Device might have moved, rendering the measurement
   data incorrect.

   A Device is able to explicitly limit the time that a LIS retains
   measurement data by adding an expiry time to the measurement data,
   see Section 4.1.2.

7.4.  Third-Party-Provided Measurement Data

   An authorized third-party request for the location of a Device (see
   [I-D.ietf-geopriv-held-identity-extensions]) can include location-
   related measurement data.  This is possible where the third-party is
   able to make observations about the Device.

   A third-party that provides measurement data MUST be authorized to
   provide the specific measurement for the identified device.  A third-



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   party MUST either be trusted by the LIS for the purposes of providing
   measurement data of the provided type, or the measurement data MUST
   be validated (see Section 8.2.1) before being used.

   How a third-party authenticates its identity or gains authorization
   to use measurement data is not covered by this document.


8.  Security Considerations

   Use of location-related measurement data has privacy considerations
   that are discussed in Section 7.

8.1.  Threat Model

   The threat model for location-related measurement data concentrates
   on the Device providing falsified, stolen or incorrect measurement
   data.

   A Device that provides location location-related measurement data
   might use data to:

   o  acquire the location of another Device, without authorization;

   o  extract information about network topology; or

   o  coerce the LIS into providing falsified location information based
      on the measurement data.

8.1.1.  Acquiring Location Information Without Authorization

   Requiring authorization for location requests is an important part of
   privacy protections of a location protocol.  A location configuration
   protocol usually operates under a restricted policy that allows a
   requester to obtain their own location.  HELD identity extensions
   [I-D.ietf-geopriv-held-identity-extensions] allows other entities to
   be authorized, conditional on a Rule Maker providing sufficient
   authorization.

   The intent of these protections is to ensure that a location
   recipient is authorized to acquire location information.  Location-
   related measurement data could be used by an attacker to circumvent
   such authorization checks if the association between measurement data
   and Target Device is not validated by a LIS.

   A LIS can be coerced into providing location information for a Device
   that a location recipient is not authorized to receive.  A request
   identifies one Device (implicitly or explicitly), but measurement



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   data is provided for another Device.  If the LIS does not check that
   the measurement data is for the identified Device, it could
   incorrectly authorize the request.

   By using unvalidated measurement data to generate a response, the LIS
   provides information about a Device without appropriate
   authorization.

   The feasibility of this attack depends on the availability of
   information that links a Device with measurement data.  In some
   cases, measurement data that is correlated with a target is readily
   available.  For instance, LLDP measurements (Section 5.1) are
   broadcast to all nodes on the same network segment.  An attacker on
   that network segment can easily gain measurement data that relates a
   Device with measurements.

   For some types of measurement data, it's necessary for an attacker to
   know the location of the target in order to determine what
   measurements to use.  This attack is meaningless for types of
   measurement data that require that the attacker first know the
   location of the target before measurement data can be acquired or
   fabricated.  GNSS measurements (Section 5.5) share this trait with
   many wireless location determination methods.

8.1.2.  Extracting Network Topology Data

   Allowing requests with measurements might be used to collect
   information about a network topology.  This is possible if requests
   containing measurements are permitted.

   Network topology can be considered sensitive information by a network
   operator for commercial or security reasons.  While it is impossible
   to completely prevent a Device from acquiring some knowledge of
   network topology if a location service is provided, a network
   operator might desire to limit how much of this information is made
   available.

   Mapping a network topology does not require that an attacker be able
   to associate measurement data with a particular Device.  If a
   requester is able to try a number of measurements, it is possible to
   acquire information about network topology.

   It is not even necessary that the measurements are valid; random
   guesses are sufficient, provided that there is no penalty or cost
   associated with attempting to use the measurements.






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8.1.3.  Lying By Proxy

   Location information is a function of its inputs, which includes
   measurement data.  Thus, falsified measurement data can be used to
   alter the location information that is provided by a LIS.

   Some types of measurement data are relatively easy to falsify in a
   way that the resulting location information to be selected with
   little or no error.  For instance, GNSS measurements are easy to use
   for this purpose because all the contextual information necessary to
   calculate a position using measurements is broadcast by the
   satellites [HARPER].

   An attacker that falsifies measurement data gains little if they are
   the only recipients of the result.  The attacker knows that the
   location information is bad.  The attacker only gains if the
   information can somehow be attributed to the LIS by another location
   recipient.

   A recipient might evaluate the trustworthiness of the location
   information based on the credibility of its source.  By coercing the
   LIS into providing falsified location information, any credibility
   that the LIS might have - that the attacker does not - is gained by
   the attacker.

   A third-party that is reliant on the integrity of the location
   information might base an evaluation of the credibility of the
   information on the source of the information.  If that third party is
   able to attribute location information to the LIS, then an attacker
   might gain.

   Location information that is provided to the Device without any means
   to identify the LIS as its source is not subject to this attack.  The
   Device is identified as the source of the data when it distributes
   the location information to location recipients.

   An attacker gains if they are able to coerce the LIS into providing
   location information based on falsified measurement data and that
   information can be attributed to the LIS.

   Location information is attributed to the LIS either through the use
   of digital signatures or by having the location recipient directly
   interact with the LIS.  A LIS that digitally signs location
   information becomes identifiable as the source of the data.
   Similarly, the LIS is identified as a source of data if a location
   recipient acquires information directly from a LIS using a location
   URI.




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8.1.4.  Measurement Replay

   The value of some measured properties do not change over time for a
   single location.  This allows for simple replay attacks, where an
   attacker acquires measurements that can later be used without being
   detected as being invalid.

   Measurement data is frequently an observation of an time-invariant
   property of the environment at the subject location.  For
   measurements of this nature, nothing in the measurement itself is
   sufficient proof that the Device is present at the resulting
   location.  Measurement data might have been previously acquired and
   reused.

   For instance, the identity of a radio transmitter, if broadcast by
   that transmitter, can be collected and stored.  An attacker that
   wishes it known that they exist at a particular location, can claim
   to observe this transmitter at any time.  Nothing inherent in the
   claim reveals it to be false.

   For properties of a network, time-invariance is often directly as a
   result of the practicalities of operating the network.  Limiting the
   changes to a network ensures greater consistency of service.  A
   largely static network also greatly simplifies the data management
   tasks involved with providing a location service.

8.2.  Mitigation

   The following measures can be applied to limit or prevent attacks.
   The effectiveness of each depends on the type of measurement data and
   how that measurement data is acquired.

   Two general approaches are identified for dealing with untrusted
   measurement data:

   1.  Require independent validation of measurement data or the
       location information that is produced.

   2.  Identify the types of sources that provided the measurement data
       that location information was derived from.

   This section goes into more detail on the different forms of
   validation in Section 8.2.1, Section 8.2.2, and Section 8.2.3.  The
   impact of attributing location information to sources is discussed in
   more detail in Section 8.2.4.






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8.2.1.  Measurement Validation

   Detecting that measurement data has been falsified is difficult in
   the absence of integrity mechanisms.

   Independent confirmation of the veracity of measurement data ensures
   that the measurement is accurate and that it applies to the correct
   Device.  By gathering the same measurement data from a trusted and
   independent source, the LIS is able to check that the measurement
   data is correct.

   Measurement information might contain no inherent indication that it
   is falsified.  On the contrary, it can be difficult to obtain
   information that would provide any degree of assurance that the
   measurement device is physically at any particular location.
   Measurements that are difficult to verify require other forms of
   assurance before they can be used.

8.2.1.1.  Effectiveness

   Measurement validation MUST be used if measurement data for a
   particular Device can be easily acquired by unauthorized location
   recipients, as described in Section 8.1.1.  This prevents
   unauthorized access to location information using measurement data.

   Validation of measurement data can be significantly more effective
   than independent acquisition of the same.  For instance, a Device in
   a large Ethernet network could provide a measurement indicating its
   point of attachment using LLDP measurements.  For a LIS, acquiring
   the same measurement data might require a request to all switches in
   that network.  With the measurement data, validation can target the
   identified switch with a specific query.

   Validation is effective in identifying falsified measurement data
   (Section 8.1.3), including attacks involving replay of measurement
   data (Section 8.1.4).  Validation also limits the amount of network
   topology information (Section 8.1.2) made available to Devices to
   that portion of the network topology that they are directly attached.

8.2.1.2.  Limitations (Unique Observer)

   A Device is often in a unique position to make a measurement.  It
   alone occupies the point in space-time that the location
   determination process seeks to determine.  The Device becomes a
   unique observer for a particular property.

   The ability of the Device to become a unique observer makes the
   Device invaluable to the location determination process.  As a unique



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   observer, it also makes the claims of a Device difficult to validate
   and easily to spoof.

   As long as no other entity is capable of making the same
   measurements, there is also no other entity that can independently
   check that the measurements are correct and applicable to the Device.
   A LIS might be unable to validate all or part of the measurement data
   it receives from a unique observer.  For instance, a signal strength
   measurement of the signal from a radio tower cannot be validated
   directly.

   Some portion of the measurement data might still be independently
   verified, even if all information cannot.  In the previous example,
   the radio tower might be able to provide verification that the Device
   is present if it is able to observe a radio signal sent by the
   Device.

   If measurement data can only be partially validated, the extent to
   which it can be validated determines the effectiveness of validation
   against these attacks.

   The advantage of having the Device as a unique observer is that it
   makes it difficult for an attacker to acquire measurements without
   the assistance of the Device.  Attempts to use measurements to gain
   unauthorized access to measurement data (Section 8.1.1) are largely
   ineffectual against a unique observer.

8.2.2.  Location Validation

   Location information that is derived from location-related
   measurement data can also be verified against trusted location
   information.  Rather than validating inputs to the location
   determination process, suspect locations are identified at the output
   of the process.

   Trusted location information is acquired using sources of measurement
   data that are trusted.  Untrusted location information is acquired
   using measurement data provided from untrusted sources, which might
   include the Device.  These two locations are compared.  If the
   untrusted location agrees with the trusted location, the untrusted
   location information is used.

   Algorithms for the comparison of location information are not
   included in this document.  However, a simple comparison for
   agreement might require that the untrusted location be entirely
   contained within the uncertainty region of the trusted location.

   There is little point in using a less accurate, less trusted



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   location.  Untrusted location information that has worse accuracy
   than trusted information can be immediately discarded.  There are
   multiple factors that affect accuracy, uncertainty and currency being
   the most important.  How location information is compared for
   accuracy is not defined in this document.

8.2.2.1.  Effectiveness

   Location validation limits the extent to which falsified - or
   erroneous - measurement data can cause an incorrect location to be
   reported.

   Location validation can be more efficient than validation of inputs,
   particularly for a unique observer (Section 8.2.1.2).

   Validating location ensures that the Device is at or near the
   resulting location.  Location validation can be used to limit or
   prevent all of the attacks identified in this document.

8.2.2.2.  Limitations

   The trusted location that is used for validation is always less
   accurate than the location that is being checked.  The amount by
   which the untrusted location is more accurate, is the same amount
   that an attacker can exploit.

   For example, a trusted location might indicate a five kilometer
   radius uncertainty region.  An untrusted location that describes a
   100 meter uncertainty within the larger region might be accepted as
   more accurate.  An attacker might still falsify measurement data to
   select any location within the larger uncertainty region.  While the
   100 meter uncertainty that is reported seems more accurate, a
   falsified location could be anywhere in the five kilometer region.

   Where measurement data might have been falsified, the actual
   uncertainty is effectively much higher.  Local policy might allow
   differing degrees of trust to location information derived from
   untrusted measurement data.  This might not be a boolean operation
   with only two possible outcomes: untrusted location information might
   be used entirely or not at all, or it could be combined with trusted
   location information with the degree to which each contributes based
   on a value set in local policy.

8.2.3.  Supporting Observations

   Replay attacks using previously acquired measurement data are
   particularly hard to detect without independent validation.  Rather
   than validate the measurement data directly, supplementary data might



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   be used to validate measurements or the location information derived
   from those measurements.

   These supporting observations could be used to convey information
   that provides additional assurance that the Device was acquired at a
   specific time and place.  In effect, the Device is requested to
   provide proof of its presence at the resulting location.

   For instance, a Device that measures attributes of a radio signal
   could also be asked to provide a sample of the measured radio signal.
   If the LIS is able to observe the same signal, the two observations
   could be compared.  Providing that the signal cannot be predicted in
   advance by the Device, this could be used to support the claim that
   the Device is able to receive the signal.  Thus, the Device is likely
   to be within the range that the signal is transmitted.  A LIS could
   use this to attribute a higher level of trust in the associated
   measurement data or resulting location.

8.2.3.1.  Effectiveness

   The use of supporting observations is limited by the ability of the
   LIS to acquire and validate these observations.  The advantage of
   selecting observations independent of measurement data is that
   observations can be selected based on how readily available the data
   is for both LIS and Device.  The amount and quality of the data can
   be selected based on the degree of assurance that is desired.

   Use of supporting observations is similar to both measurement
   validation and location validation.  All three methods rely on
   independent validation of one or more properties.  Applicability of
   each method is similar.

   Use of supporting observations can be used to limit or prevent all of
   the attacks identified in this document.

8.2.3.2.  Limitations

   The effectiveness of the validation method depends on the quality of
   the supporting observation: how hard it is to obtain at a different
   time or place, how difficult it is to guess and what other costs
   might be involved in acquiring this data.

   In the example of an observed radio signal, requesting a sample of
   the signal only provides an assurance that the Device is able to
   receive the signal transmitted by the measured radio transmitter.
   This only provides some assurance that the Device is within range of
   the transmitter.




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   As with location validation, a Device might still be able to provide
   falsified measurements that could alter the value of the location
   information as long as the result is within this region.

   Requesting additional supporting observations can reduce the size of
   the region over which location information can be altered by an
   attacker, or increase trust in the result, but each additional has a
   cost.  Supporting observations contribute little or nothing toward
   the primary goal of determining the location of the Device.  Any
   costs in acquiring supporting observations are balanced against the
   degree of integrity desired of the resulting location information.

8.2.4.  Attribution

   Lying by proxy (Section 8.1.3) relies on the location recipient being
   able to attribute location information to a LIS.  The effectiveness
   of this attack is negated if location information is explicitly
   attributed to a particular source.

   This requires an extension to the location object that explicitly
   identifies the source (or sources) of each item of location
   information.

   Rather than relying on a process that seeks to ensure that location
   information is accurate, this approach instead provides a location
   recipient with the information necessary to reach their own
   conclusion about the trustworthiness of the location information.

   Including an authenticated identity for all sources of measurement
   data is presents a number of technical and operational challenges.
   It is possible that the LIS has a transient relationship with a
   Device.  A Device is not expected to share authentication information
   with a LIS.  There is no assurance that Device identification is
   usable by a potential location recipient.  Privacy concerns might
   also prevent the sharing identification information, even if it were
   available and usable.

   Identifying the type of measurement source allows a location
   recipient to make a decision about the trustworthiness of location
   information without depending on having authenticated identity
   information for each source.  An element for this purpose is defined
   in Section 4.4.

   When including location information that is based on measurement data
   from sources that might be untrusted, a LIS SHOULD include
   alternative location information that is derived from trusted sources
   of measurement data.  Each item of location information can then be
   labelled with the source of that data.



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   A location recipient that is able to identify a specific source of
   measurement data (whether it be LIS or Device) can use this
   information to attribute location information to either or both
   entity.  The location recipient is then better able to make decisions
   about trustworthiness based on the source of the data.

   A location recipient that does not understand the "source" element is
   unable to make this distinction.  When constructing a PIDF-LO
   document, trusted location information MUST be placed in the PIDF-LO
   so that it is given higher priority to any untrusted location
   information according to Rule #8 of [RFC5491].

8.2.5.  Stateful Correlation of Location Requests

   Stateful examination of requests can be used to prevent a Device from
   attempting to map network topology using requests for location
   information (Section 8.1.2).

   Simply limiting the rate of requests from a single Device reduces the
   amount of data that a Device can acquire about network topology.


9.  IANA Considerations

   This section creates a registry for GNSS types (Section 5.5) and
   registers the namespaces and schema defined in Section 6.

9.1.  IANA Registry for GNSS Types

   This document establishes a new IANA registry for Global Navigation
   Satellite System (GNSS) types.  The registry includes tokens for the
   GNSS type and for each of the signals within that type.  Referring to
   [RFC5226], this registry operates under "Specification Required"
   rules.  The IESG will appoint an Expert Reviewer who will advise IANA
   promptly on each request for a new or updated GNSS type.

   Each entry in the registry requires the following information:

   GNSS name:  the name and a brief description of the GNSS

   Brief description:  the name and a brief description of the GNSS

   GNSS token:  a token that can be used to identify the GNSS

   Signals:  a set of tokens that represent each of the signals that the
      system provides





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   Documentation reference:  a reference to one or more stable, public
      specifications that outline usage of the GNSS, including (but not
      limited to) signal specifications and time systems

   The registry initially includes two registrations:

   GNSS name:  Global Positioning System (GPS)

   Brief description:  a system of satellites that use spread-spectrum
      transmission, operated by the US military for commercial and
      military applications

   GNSS token:  gps

   Signals:  L1, L2, L1C, L2C, L5

   Documentation reference:  Navstar GPS Space Segment/Navigation User
      Interface [GPS.ICD]

   GNSS name:  Galileo

   Brief description:  a system of satellites that operate in the same
      spectrum as GPS, operated by the European Union for commercial
      applications

   GNSS Token:  galileo

   Signals:  L1, E5A, E5B, E5A+B, E6

   Documentation Reference:  Galileo Open Service Signal In Space
      Interface Control Document (SIS ICD) [Galileo.ICD]

9.2.  URN Sub-Namespace Registration for
      urn:ietf:params:xml:ns:pidf:geopriv10:lmsrc

   This section registers a new XML namespace,
   "urn:ietf:params:xml:ns:pidf:geopriv10:lmsrc", as per the guidelines
   in [RFC3688].

      URI: urn:ietf:params:xml:ns:pidf:geopriv10:lmsrc

      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>Measurement Source for PIDF-LO</title>
             </head>
             <body>
               <h1>Namespace for Location Measurement Source</h1>
               <h2>urn:ietf:params:xml:ns:pidf:geopriv10:lmsrc</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:geopriv:lm

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

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

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

      XML:

         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>Measurement Container</title>
             </head>
             <body>
               <h1>Namespace for Location Measurement Container</h1>
               <h2>urn:ietf:params:xml:ns:geopriv: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>



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         END

9.4.  URN Sub-Namespace Registration for
      urn:ietf:params:xml:ns:geopriv:lm:basetypes

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

      URI: urn:ietf:params:xml:ns:geopriv:lm:basetypes

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

      XML:

         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>Base Device Types</title>
             </head>
             <body>
               <h1>Namespace for Base Types</h1>
               <h2>urn:ietf:params:xml:ns:geopriv:lm:basetypes</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

9.5.  URN Sub-Namespace Registration for
      urn:ietf:params:xml:ns:geopriv:lm:lldp

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

      URI: urn:ietf:params:xml:ns:geopriv:lm:lldp

      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>LLDP Measurement Set</title>
             </head>
             <body>
               <h1>Namespace for LLDP Measurement Set</h1>
               <h2>urn:ietf:params:xml:ns:geopriv:lm:lldp</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.  URN Sub-Namespace Registration for
      urn:ietf:params:xml:ns:geopriv:lm:dhcp

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

      URI: urn:ietf:params:xml:ns:geopriv:lm:dhcp

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

      XML:

         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>DHCP Measurement Set</title>
             </head>
             <body>
               <h1>Namespace for DHCP Measurement Set</h1>
               <h2>urn:ietf:params:xml:ns:geopriv:lm:dhcp</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>



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         END

9.7.  URN Sub-Namespace Registration for
      urn:ietf:params:xml:ns:geopriv:lm:wifi

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

      URI: urn:ietf:params:xml:ns:geopriv:lm:wifi

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

      XML:

         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>WiFi Measurement Set</title>
             </head>
             <body>
               <h1>Namespace for WiFi Measurement Set</h1>
               <h2>urn:ietf:params:xml:ns:geopriv:lm:wifi</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

9.8.  URN Sub-Namespace Registration for
      urn:ietf:params:xml:ns:geopriv:lm:cell

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

      URI: urn:ietf:params:xml:ns:geopriv:lm:cell

      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>Cellular Measurement Set</title>
             </head>
             <body>
               <h1>Namespace for Cellular Measurement Set</h1>
               <h2>urn:ietf:params:xml:ns:geopriv:lm:cell</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

9.9.  URN Sub-Namespace Registration for
      urn:ietf:params:xml:ns:geopriv:lm:gnss

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

      URI: urn:ietf:params:xml:ns:geopriv:lm:gnss

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

      XML:

         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>GNSS Measurement Set</title>
             </head>
             <body>
               <h1>Namespace for GNSS Measurement Set</h1>
               <h2>urn:ietf:params:xml:ns:geopriv:lm:gnss</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>



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         END

9.10.  URN Sub-Namespace Registration for
       urn:ietf:params:xml:ns:geopriv:lm:dsl

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

      URI: urn:ietf:params:xml:ns:geopriv:lm:dsl

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

      XML:

         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>DSL Measurement Set</title>
             </head>
             <body>
               <h1>Namespace for DSL Measurement Set</h1>
               <h2>urn:ietf:params:xml:ns:geopriv:lm:dsl</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

9.11.  XML Schema Registration for Measurement Source Schema

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

   URI:  urn:ietf:params:xml:schema:pidf:geopriv10:lmsrc

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

   Schema:  The XML for this schema can be found in Section 6.2 of this
      document.





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9.12.  XML Schema Registration for Measurement Container Schema

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

   URI:  urn:ietf:params:xml:schema:lm

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

   Schema:  The XML for this schema can be found in Section 6.1 of this
      document.

9.13.  XML Schema Registration for Base Types Schema

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

   URI:  urn:ietf:params:xml:schema:lm:basetypes

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

   Schema:  The XML for this schema can be found in Section 6.3 of this
      document.

9.14.  XML Schema Registration for LLDP Schema

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

   URI:  urn:ietf:params:xml:schema:lm:lldp

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

   Schema:  The XML for this schema can be found in Section 6.4 of this
      document.

9.15.  XML Schema Registration for DHCP Schema

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

   URI:  urn:ietf:params:xml:schema:lm:dhcp






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

   Schema:  The XML for this schema can be found in Section 6.5 of this
      document.

9.16.  XML Schema Registration for WiFi Schema

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

   URI:  urn:ietf:params:xml:schema:lm:wifi

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

   Schema:  The XML for this schema can be found in Section 6.6 of this
      document.

9.17.  XML Schema Registration for Cellular Schema

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

   URI:  urn:ietf:params:xml:schema:lm:cellular

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

   Schema:  The XML for this schema can be found in Section 6.7 of this
      document.

9.18.  XML Schema Registration for GNSS Schema

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

   URI:  urn:ietf:params:xml:schema:lm:gnss

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

   Schema:  The XML for this schema can be found in Section 6.8 of this
      document.







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9.19.  XML Schema Registration for DSL Schema

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

   URI:  urn:ietf:params:xml:schema:lm:dsl

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

   Schema:  The XML for this schema can be found in Section 6.9 of this
      document.


10.  Acknowledgements

   Thanks go to Simon Cox for his comments relating to terminology that
   have helped ensure that this document is aligns with ongoing work in
   the Open Geospatial Consortium (OGC).  Thanks to Neil Harper for his
   review and comments on the GNSS sections of this document.  Thanks to
   Noor-E-Gagan Singh and Gabor Bajko for independent suggestions for
   improving the parameters associated with 802.11 measurements.  Thanks
   to Cullen Jennings for feedback and suggestions.


11.  References

11.1.  Normative References

   [DSL.TR025]
              Wang, R., "Core Network Architecture Recommendations for
              Access to Legacy Data Networks over ADSL", September 1999.

   [DSL.TR101]
              Cohen, A. and E. Shrum, "Migration to Ethernet-Based DSL
              Aggregation", April 2006.

   [GPS.ICD]  "Navstar GPS Space Segment/Navigation User Interface",
              ICD GPS-200, Apr 2000.

   [Galileo.ICD]
              GJU, "Galileo Open Service Signal In Space Interface
              Control Document (SIS ICD)", May 2006.

   [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-16 (work in



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              progress), August 2009.

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

   [RFC4119]  Peterson, J., "A Presence-based GEOPRIV Location Object
              Format", RFC 4119, December 2005.

   [RFC5226]  Narten, T. and H. Alvestrand, "Guidelines for Writing an
              IANA Considerations Section in RFCs", BCP 26, RFC 5226,
              May 2008.

   [RFC5491]  Winterbottom, J., Thomson, M., and H. Tschofenig, "GEOPRIV
              Presence Information Data Format Location Object (PIDF-LO)
              Usage Clarification, Considerations, and Recommendations",
              RFC 5491, March 2009.

11.2.  Informative References

   [HARPER]   Harper, N., Dawson, M., and D. Evans, "Server-side
              spoofing and detection for Assisted-GPS", Proceedings of
              International Global Navigation Satellite Systems Society
              (IGNSS) Symposium 2009 16, December 2009,
              <http://ignss.org/files/Paper16.pdf>.

   [I-D.ietf-geopriv-held-identity-extensions]
              Winterbottom, J., Thomson, M., Tschofenig, H., and R.
              Barnes, "Use of Device Identity in HTTP-Enabled Location
              Delivery (HELD)",
              draft-ietf-geopriv-held-identity-extensions-03 (work in
              progress), February 2010.

   [I-D.thomson-geopriv-uncertainty]
              Thomson, M. and J. Winterbottom, "Representation of
              Uncertainty and Confidence in PIDF-LO",
              draft-thomson-geopriv-uncertainty-04 (work in progress),
              November 2009.

   [IANA.enterprise]
              IANA, "Private Enterprise Numbers",
              <http://www.iana.org/assignments/enterprise-numbers>.

   [IEEE.8021AB]
              IEEE, "IEEE Standard for Local and Metropolitan area
              networks, Station and Media Access Control Connectivity
              Discovery",  802.1AB, June 2005.

   [RFC2865]  Rigney, C., Willens, S., Rubens, A., and W. Simpson,



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              "Remote Authentication Dial In User Service (RADIUS)",
              RFC 2865, June 2000.

   [RFC3046]  Patrick, M., "DHCP Relay Agent Information Option",
              RFC 3046, January 2001.

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

   [RFC3693]  Cuellar, J., Morris, J., Mulligan, D., Peterson, J., and
              J. Polk, "Geopriv Requirements", RFC 3693, February 2004.

   [RFC3993]  Johnson, R., Palaniappan, T., and M. Stapp, "Subscriber-ID
              Suboption for the Dynamic Host Configuration Protocol
              (DHCP) Relay Agent Option", RFC 3993, March 2005.

   [RFC4291]  Hinden, R. and S. Deering, "IP Version 6 Addressing
              Architecture", RFC 4291, February 2006.

   [RFC4580]  Volz, B., "Dynamic Host Configuration Protocol for IPv6
              (DHCPv6) Relay Agent Subscriber-ID Option", RFC 4580,
              June 2006.

   [RFC4649]  Volz, B., "Dynamic Host Configuration Protocol for IPv6
              (DHCPv6) Relay Agent Remote-ID Option", RFC 4649,
              August 2006.

   [RFC5808]  Marshall, R., "Requirements for a Location-by-Reference
              Mechanism", RFC 5808, May 2010.


Authors' Addresses

   Martin Thomson
   Andrew
   Andrew Building (39)
   University of Wollongong
   Northfields Avenue
   Wollongong, NSW  2522
   AU

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







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   James Winterbottom
   Andrew
   Andrew Building (39)
   University of Wollongong
   Northfields Avenue
   NSW  2522
   AU

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








































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