Internet Engineering Task Force (IETF)                        M. Thomson
Request for Comments: 7105                                       Mozilla
Category: Standards Track                                J. Winterbottom
ISSN: 2070-1721                                             Unaffiliated
                                                           January 2014


         Using Device-Provided Location-Related Measurements
                 in Location Configuration Protocols

Abstract

  This document describes a protocol for a Device to provide location-
  related measurement data to a Location Information Server (LIS)
  within a request for location information.  Location-related
  measurement information provides observations concerning properties
  related to the position of a Device; this information could be data
  about network attachment or about the physical environment.  A LIS is
  able to use the location-related measurement data to improve the
  accuracy of the location estimate it provides to the Device.  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 is an Internet Standards Track document.

  This document is a product of the Internet Engineering Task Force
  (IETF).  It represents the consensus of the IETF community.  It has
  received public review and has been approved for publication by the
  Internet Engineering Steering Group (IESG).  Further information on
  Internet Standards is available in Section 2 of RFC 5741.

  Information about the current status of this document, any errata,
  and how to provide feedback on it may be obtained at
  http://www.rfc-editor.org/info/rfc7105.














Thomson & Winterbottom       Standards Track                    [Page 1]

RFC 7105                  Location Measurements             January 2014


Copyright Notice

  Copyright (c) 2014 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
  publication of this document.  Please review these documents
  carefully, as they describe your rights and restrictions with respect
  to this document.  Code Components extracted from this document must
  include Simplified BSD License text as described in Section 4.e of
  the Trust Legal Provisions and are provided without warranty as
  described in the Simplified BSD License.

Table of Contents

  1. Introduction ....................................................4
  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 ......................................7
          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 .................14
     5.3. 802.11 WLAN Measurements ..................................15
          5.3.1. WiFi Measurement Requests ..........................18
     5.4. Cellular Measurements .....................................18
          5.4.1. Cellular Measurement Requests ......................22
     5.5. GNSS Measurements .........................................22
          5.5.1. GNSS: System Type and Signal .......................23
          5.5.2. Time ...............................................24
          5.5.3. Per-Satellite Measurement Data .....................24
          5.5.4. GNSS Measurement Requests ..........................25
     5.6. DSL Measurements ..........................................25
          5.6.1. L2TP Measurements ..................................26
          5.6.2. RADIUS Measurements ................................26
          5.6.3. Ethernet VLAN Tag Measurements .....................27
          5.6.4. ATM Virtual Circuit Measurements ...................28






Thomson & Winterbottom       Standards Track                    [Page 2]

RFC 7105                  Location Measurements             January 2014


  6. Privacy Considerations .........................................28
     6.1. Measurement Data Privacy Model ............................28
     6.2. LIS Privacy Requirements ..................................29
     6.3. Measurement Data and Location URIs ........................29
     6.4. Measurement Data Provided by a Third Party ................30
  7. Security Considerations ........................................30
     7.1. Threat Model ..............................................30
          7.1.1. Acquiring Location Information without
                 Authorization ......................................31
          7.1.2. Extracting Network Topology Data ...................32
          7.1.3. Exposing Network Topology Data .....................32
          7.1.4. Lying by Proxy .....................................33
          7.1.5. Measurement Replay .................................33
          7.1.6. Environment Spoofing ...............................34
     7.2. Mitigation ................................................35
          7.2.1. Measurement Validation .............................36
                 7.2.1.1. Effectiveness .............................36
                 7.2.1.2. Limitations (Unique Observer) .............37
          7.2.2. Location Validation ................................38
                 7.2.2.1. Effectiveness .............................38
                 7.2.2.2. Limitations ...............................39
          7.2.3. Supporting Observations ............................39
                 7.2.3.1. Effectiveness .............................40
                 7.2.3.2. Limitations ...............................40
          7.2.4. Attribution ........................................40
          7.2.5. Stateful Correlation of Location Requests ..........42
     7.3. An Unauthorized or Compromised LIS ........................42
  8. Measurement Schemas ............................................42
     8.1. Measurement Container Schema ..............................43
     8.2. Measurement Source Schema .................................45
     8.3. Base Types Schema .........................................46
     8.4. LLDP Measurement Schema ...................................49
     8.5. DHCP Measurement Schema ...................................50
     8.6. WiFi Measurement Schema ...................................51
     8.7. Cellular Measurement Schema ...............................55
     8.8. GNSS Measurement Schema ...................................57
     8.9. DSL Measurement Schema ....................................59
  9. IANA Considerations ............................................61
     9.1. IANA Registry for GNSS Types ..............................61
     9.2. URN Sub-Namespace Registration for
          urn:ietf:params:xml:ns:pidf:geopriv10:lmsrc ...............62
     9.3. URN Sub-Namespace Registration for
          urn:ietf:params:xml:ns:geopriv:lm .........................63
     9.4. URN Sub-Namespace Registration for
          urn:ietf:params:xml:ns:geopriv:lm:basetypes ...............63
     9.5. URN Sub-Namespace Registration for
          urn:ietf:params:xml:ns:geopriv:lm:lldp ....................64




Thomson & Winterbottom       Standards Track                    [Page 3]

RFC 7105                  Location Measurements             January 2014


     9.6. URN Sub-Namespace Registration for
          urn:ietf:params:xml:ns:geopriv:lm:dhcp ....................65
     9.7. URN Sub-Namespace Registration for
          urn:ietf:params:xml:ns:geopriv:lm:wifi ....................65
     9.8. URN Sub-Namespace Registration for
          urn:ietf:params:xml:ns:geopriv:lm:cell ....................66
     9.9. URN Sub-Namespace Registration for
          urn:ietf:params:xml:ns:geopriv:lm:gnss ....................67
     9.10. URN Sub-Namespace Registration for
           urn:ietf:params:xml:ns:geopriv:lm:dsl ....................67
     9.11. XML Schema Registration for Measurement Source Schema ....68
     9.12. XML Schema Registration for Measurement Container
           Schema ...................................................68
     9.13. XML Schema Registration for Base Types Schema ............69
     9.14. XML Schema Registration for LLDP Schema ..................69
     9.15. XML Schema Registration for DHCP Schema ..................69
     9.16. XML Schema Registration for WiFi Schema ..................69
     9.17. XML Schema Registration for Cellular Schema ..............70
     9.18. XML Schema Registration for GNSS Schema ..................70
     9.19. XML Schema Registration for DSL Schema ...................70
  10. Acknowledgements ..............................................70
  11. References ....................................................71
     11.1. Normative References .....................................71
     11.2. Informative References ...................................73

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 that is available due to the knowledge
  it has about the network and physical environment.

  As a part of the access network, the LIS is able to acquire
  measurement results related to Device location from network elements.
  The LIS also has access to information about the network topology
  that can be used to turn measurement data into location information.
  This information can be further 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 terms of time or some
  other metric.  Providing measurement data gives the LIS more options
  in determining location; this could in turn improve the quality of





Thomson & Winterbottom       Standards Track                    [Page 4]

RFC 7105                  Location Measurements             January 2014


  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
  HTTP-Enabled Location Delivery (HELD) [RFC5985] 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 [RFC5985].

  This document also uses the following definitions:

  Location Measurement:  An observation about the physical properties
     of a particular Device's position in time and space.  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 directly identify a Device, though it
     could do so indirectly.  Measurement data can change with time if
     the location of the Device also changes.

     Location-related measurement data does not necessarily contain
     location information directly, but it can be used in combination
     with contextual knowledge and/or algorithms to derive location
     information.  Examples of location-related measurement data are
     radio signal strength or timing measurements, Ethernet switch
     identifiers, and port identifiers.

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

  Location Estimate:  An approximation of where the Device is located.
     Location estimates are derived from location measurements.
     Location estimates are subject to uncertainty, which arises 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].




Thomson & Winterbottom       Standards Track                    [Page 5]

RFC 7105                  Location Measurements             January 2014


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.

  A simple 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 the
  Link-Layer Discovery Protocol (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>

          Figure 1: HELD Location Request with Measurement Data

  This LIS can ignore measurement data that it does not support or
  understand.  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.

  A LIS can choose to use or ignore location-related measurement data
  in determining location, as long as rules regarding use and retention
  (Section 6) are respected.  The "method" parameter in the Presence
  Information Data Format - Location Object (PIDF-LO) [RFC4119] SHOULD
  be adjusted to reflect the method used.  A correct "method" can
  assist location recipients in assessing the quality (both accuracy
  and integrity) of location information, though there could be reasons
  to withhold information about the source of data.






Thomson & Winterbottom       Standards Track                    [Page 6]

RFC 7105                  Location Measurements             January 2014


  Measurement data is typically only used to serve the request in which
  it is included.  There may be exceptions, particularly with respect
  to location URIs.  Section 6 provides more information on usage
  rules.

  Location-related measurement data need not be provided exclusively by
  Devices.  A third-party location requester (for example, see
  [RFC6155]) can request location information using measurement data,
  if the requester is able to acquire measurement data and authorized
  to distribute it.  There are specific privacy considerations relating
  to the use of measurements by third parties, which are discussed in
  Section 6.4.

  Location-related measurement data and its use present a number of
  privacy and security challenges.  These are described in more detail
  in Sections 6 and 7.

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">
        <ap serving="true">
          <bssid>00-12-F0-A0-80-EF</bssid>
          <ssid>wlan-home</ssid>
        </ap>
      </wifi>
    </lm:measurements>

                      Figure 2: Measurement Example

4.1.  Measurement Container

  The "measurements" 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 it
  permits the inclusion of arbitrary measurement data.  The elements
  that are included within the "measurements" element are generically
  referred to as "measurement elements".




Thomson & Winterbottom       Standards Track                    [Page 7]

RFC 7105                  Location Measurements             January 2014


  This container can be added to a request for location information in
  any protocol capable of carrying XML, such as a HELD location request
  [RFC5985].

4.1.1.  Time of Measurement

  The "time" attribute records the time that the measurement or
  observation was made.  This time can be different from 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 SHOULD be provided whenever possible.  This
  allows a LIS to avoid selecting an arbitrary timestamp.  Exceptions
  to this, where omitting time might make sense, include relatively
  static types of measurement (for instance, the DSL measurements in
  Section 5.6) or for legacy Devices that don't record time information
  (such as the Home Location Register/Home Subscriber Server for
  cellular).

  The "time" attribute is attached to the root "measurement" element.
  Multiple measurements can often be given the same timestamp, even
  when the measurements were not actually taken at the same time
  (consider a set of measurements taken sequentially, where the
  difference in time between observations is not significant).
  Measurements cannot be grouped if they have different types or if
  there is a need for independent time values on each measurement.  In
  these instances, multiple measurement sets are necessary.

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, but it can
  also indicate a time limit on the retention and use of the
  measurement data.  A Device can use this attribute to request that
  the LIS not retain measurement data beyond the indicated time.

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

  A Device is advised to set the "expires" attribute to the earlier of
  the time that measurements are likely to be unusable and the time
  that it desires to have measurements discarded by the LIS.  A Device
  that does not desire measurement data to be retained can omit the
  "expires" attribute.  Section 6 describes more specific rules
  regarding measurement data retention.




Thomson & Winterbottom       Standards Track                    [Page 8]

RFC 7105                  Location Measurements             January 2014


4.2.  RMS Error and Number of Samples

  Often a measurement is taken more than once.  Reporting the average
  of a number of measurement results mitigates the effects of random
  errors that occur in the measurement process.

  Reporting each measurement individually can be the most effective
  method of reporting multiple measurements.  This is achieved by
  providing multiple measurement elements for different times.

  The alternative is to aggregate multiple measurements and report a
  mean value across the set of measurements.  Additional information
  about the distribution of the results can be useful in determining
  location uncertainty.

  Two attributes are provided for use on some 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 the RMS error is not known, this
     value can be used to indicate an upper bound or estimate 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
     large enough 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 the RMS error does not need to
  be actively measured.  A fixed value MAY be provided for the 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 synchronization can result in
  small, but significant, time errors.  Including an indication of the
  quality of time measurements can be helpful.




Thomson & Winterbottom       Standards Track                    [Page 9]

RFC 7105                  Location Measurements             January 2014


  A "timeError" attribute MAY 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 are taken over time.  If multiple samples are taken, each
  SHOULD be included in a different "measurement" element.

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.  A "samples" attribute MAY be used to indicate 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 non-mandatory 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 an
  error response with a code of "locationUnknown" indicates that
  providing measurements would increase the likelihood of a subsequent
  request being successful.













Thomson & Winterbottom       Standards Track                   [Page 10]

RFC 7105                  Location Measurements             January 2014


  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:parameter context="ap">wifi:rcpi</wifi:parameter>
        </measurement>
      </measurementRequest>
    </error>

            Figure 3: HELD Error Requesting Measurement Data

  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 measurement source.

  The following values are defined for the "source" element:

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

  device:  A LIS MUST include this value if the location information is
     based (in whole or in part) on measurement data provided by the
     Device and if the measurement data isn't completely validated.





Thomson & Winterbottom       Standards Track                   [Page 11]

RFC 7105                  Location Measurements             January 2014


  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 [RFC6155] or any other entity.  The
     LIS MUST include this, unless the third party is trusted by the
     LIS to provide measurement data.

  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 multiple types of sources was
  used.

  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:[email protected]">
      <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>



Thomson & Winterbottom       Standards Track                   [Page 12]

RFC 7105                  Location Measurements             January 2014


            </gp:location-info>
            <gp:usage-rules/>
            <gp:method>Cell</gp:method>
            <lmsrc:source>lis</lmsrc:source>
          </gp:geopriv>
        </status>
      </tuple>
    </presence>

                   PIDF-LO Document with Source Labels

5.  Location-Related Measurement Data Types

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

  All included measurement data definitions allow for arbitrary
  extension in the corresponding schema.  New parameters that are
  applicable to location determination are added as new XML elements in
  a unique namespace, not by adding elements to an existing namespace.

5.1.  LLDP Measurements

  Link-Layer Discovery Protocol (LLDP) [IEEE.8021AB] 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; the identification information 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.

     Note: The LLDP extensions defined in LLDP Media Endpoint Discovery
     (LLDP-MED) [ANSI-TIA-1057] provide the ability to acquire location
     information directly from an LLDP endpoint.  Where this
     information is available, it might be unnecessary to use any other
     form of location configuration.

  Values are provided as hexadecimal sequences.  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.





Thomson & Winterbottom       Standards Track                   [Page 13]

RFC 7105                  Location Measurements             January 2014


  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.

  The elements in the DHCP relay agent information options are opaque
  data types assigned by the DHCP relay agent.  The three items MAY be
  omitted if unknown: circuit identifier ("circuit", circuit [RFC3046],
  or Interface-Id [RFC3315]), remote identifier ("remote", Remote ID
  [RFC3046], or remote-id [RFC4649]), and subscriber identifier
  ("subscriber", subscriber-id [RFC3993], or Subscriber-ID [RFC4580]).
  The DHCPv6 remote-id 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>192.0.2.158</giaddr>
        <circuit>108b</circuit>
      </dhcp-rai>
    </measurements>

       Figure 5: DHCP Relay Agent Information Measurement Example








Thomson & Winterbottom       Standards Track                   [Page 14]

RFC 7105                  Location Measurements             January 2014


  The "giaddr" element is specified as a dotted quad IPv4 address or an
  RFC 4291 [RFC4291] IPv6 address, using the forms defined in
  [RFC3986]; IPv6 addresses SHOULD use the form described in [RFC5952].
  The enterprise number is specified as a decimal integer.  All other
  information is included verbatim from the DHCP request in hexadecimal
  format.

  The "subscriber" element could be considered sensitive.  This
  information MUST NOT be provided to a LIS that is not authorized to
  receive information about the access network.  See Section 7.1.3 for
  more details.

5.3.  802.11 WLAN Measurements

  In WiFi, or 802.11 [IEEE.80211], networks, a Device might be able to
  provide information about the access point (AP) to which it is
  attached, or other WiFi points it is able to see.  This is provided
  using the "wifi" element, as shown in Figure 6, which shows a single
  complete measurement for a single access point.

    <measurements xmlns="urn:ietf:params:xml:ns:geopriv:lm"
          time="2011-04-29T14:33:58">
      <wifi xmlns="urn:ietf:params:xml:ns:geopriv:lm:wifi">
        <nicType>Intel(r)PRO/Wireless 2200BG</nicType>
        <ap serving="true">
          <bssid>AB-CD-EF-AB-CD-EF</bssid>
          <ssid>example</ssid>
          <channel>5</channel>
          <location>
            <gml:Point xmlns:gml="http://opengis.net/gml">
              <gml:pos>-34.4 150.8</gml:pos>
            </gml:Point>
          </location>
          <type>a</type>
          <band>5</band>
          <regclass country="AU">2</regclass>
          <antenna>2</antenna>
          <flightTime rmsError="4e-9" samples="1">2.56e-9</flightTime>
          <apSignal>
            <transmit>23</transmit>
            <gain>5</gain>
            <rcpi dBm="true" rmsError="12" samples="1">-59</rcpi>
            <rsni rmsError="15" samples="1">23</rsni>
          </apSignal>
          <deviceSignal>
            <transmit>10</transmit>
            <gain>9</gain>
            <rcpi dBm="true" rmsError="9.5" samples="1">-98.5</rcpi>



Thomson & Winterbottom       Standards Track                   [Page 15]

RFC 7105                  Location Measurements             January 2014


            <rsni rmsError="6" samples="1">7.5</rsni>
          </deviceSignal>
        </ap>
      </wifi>
    </measurements>

                Figure 6: 802.11 WLAN Measurement Example

  A "wifi" element is made up of one or more access points, and a
  "nicType" element, which MAY be omitted.  Each access point is
  described using the "ap" element, which is comprised of the following
  fields:

  bssid:  The Basic Service Set (BSS) identifier.  In an Infrastructure
     BSS network, the bssid is the 48-bit MAC address of the access
     point.

     The "verified" attribute of this element describes whether the
     Device has verified the MAC address or it authenticated the access
     point or the network operating the access point (for example, a
     captive portal accessed through the access point has been
     authenticated).  This attribute defaults to a value of "false"
     when omitted.

  ssid:  The service set identifier (SSID) for the wireless network
     served by the access point.

     The SSID is a 32-octet identifier that is commonly represented as
     an ASCII [ASCII] or UTF-8 [RFC3629] encoded string.  To represent
     octets that cannot be directly included in an XML element,
     escaping is used.  Sequences of octets that do not represent a
     valid UTF-8 encoding can be escaped using a backslash ('\')
     followed by two case-insensitive hexadecimal digits representing
     the value of a single octet.

     The canonical or value-space form of an SSID is a sequence of up
     to 32 octets that is produced from the concatenation of UTF-8
     encoded sequences of unescaped characters and octets derived from
     escaped components.

  channel:  The channel number (frequency) on which the access point
     operates.

  location:  The location of the access point, as reported by the
     access point.  This element contains any valid location, using the
     rules for a "location-info" element, as described in [RFC5491].





Thomson & Winterbottom       Standards Track                   [Page 16]

RFC 7105                  Location Measurements             January 2014


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

  band:  The frequency band for the radio, in gigahertz (GHz).  802.11
     [IEEE.80211] specifies PHY layers that use 2.4, 3.7, and 5
     gigahertz frequency bands.

  regclass:  The operating class (regulatory domain and class in older
     versions of 802.11); see Annex E of [IEEE.80211].  The "country"
     attribute optionally includes the applicable two-character country
     identifier (dot11CountryString), which can be followed by an 'O',
     'I', or 'X'.  The element text content includes the value of the
     regulatory class: an 8-bit integer in decimal form.

  antenna:  The antenna identifier for the antenna that the access
     point is using to transmit the measured signals.

  flightTime:  Flight time is the difference between the time of
     departure (TOD) of signal from a transmitting station and time of
     arrival (TOA) of signal at a receiving station, as defined in
     [IEEE.80211].  Measurement of this value requires that stations
     synchronize their clocks.  This value can be measured by an access
     point or Device; because the flight time is assumed to be the same
     in either direction -- aside from measurement errors -- only a
     single element is provided.  This element permits the use of the
     "rmsError" and "samples" attributes.  RMS error might be derived
     from the reported RMS error in TOD and TOA.

  apSignal:  Measurement information for the signal transmitted by the
     access point, as observed by the Device.  Some of these values are
     derived from 802.11v [IEEE.80211] messages exchanged between the
     Device and access point.  The contents of this element include:

     transmit:  The transmit power reported by the access point,
        in dBm.

     gain:  The gain of the access point antenna reported by the access
        point, in dB.

     rcpi:  The received channel power indicator for the access point
        signal, as measured by the Device.  This value SHOULD be in
        units of dBm (with RMS error in dB).  If power is measured in a
        different fashion, the "dBm" attribute MUST be set to "false".
        Signal strength reporting on current hardware uses a range of
        different mechanisms; therefore, the value of the "nicType"
        element SHOULD be included if the units are not known to be in



Thomson & Winterbottom       Standards Track                   [Page 17]

RFC 7105                  Location Measurements             January 2014


        dBm, and the value reported by the hardware should be included
        without modification.  This element permits the use of the
        "rmsError" and "samples" attributes.

     rsni:  The received signal-to-noise indicator in dB.  This element
        permits the use of the "rmsError" and "samples" attributes.

  deviceSignal:  Measurement information for the signal transmitted by
     the Device, as reported by the access point.  This element
     contains the same child elements as the "ap" element, with the
     access point and Device roles reversed.

  The only mandatory element in this structure is "bssid".

  The "nicType" element is used to specify the make and model of the
  wireless network interface in the Device.  Different 802.11 chipsets
  report measurements in different ways, so knowing the network
  interface type aids the LIS in determining how to use the provided
  measurement data.  The content of this field is unconstrained, and no
  mechanisms are specified to ensure uniqueness.  This field is
  unlikely to be useful, except under tightly controlled circumstances.

5.3.1.  WiFi Measurement Requests

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

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

  parameter:  The "parameter" element identifies measurements that are
     requested for each measured access point.  An element is
     identified by its qualified name.  The "context" parameter can be
     used to specify if an element is included as a child of the "ap"
     or "device" elements; omission indicates that it applies to both.

  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.
  Cellular measurements can be provided to a LIS run by the cellular
  operator, or may be provided to an alternative LIS operator that has
  access to one of several global cell-id to location mapping
  databases.




Thomson & Winterbottom       Standards Track                   [Page 18]

RFC 7105                  Location Measurements             January 2014


  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 Third Generation Partnership Project (3GPP)
  cells are identified by a public land mobile network (PLMN), which
  comprises a mobile country code (MCC) and mobile network code (MNC);
  specific fields are added for each network type.

  Formats for 3GPP cell identifiers are described in [TS.3GPP.23.003].
  Bit-level formats for CDMA cell identifiers are described in
  [TIA-2000.5]; decimal representations are used.

  MCC and MNC are provided as decimal digit sequences; a leading zero
  in an MCC or MNC is significant.  All other values are decimal
  integers.

    <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











Thomson & Winterbottom       Standards Track                   [Page 19]

RFC 7105                  Location Measurements             January 2014


    <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 a
  12- or 16-bit radio network controller (rnc) id and a 16-bit cell id
  (cid).

               Figure 8: Example UMTS 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>06</mnc>
          <lac>16383</lac><cid>32767</cid>
        </servingCell>
      </cellular>
    </measurements>

  Global System for Mobile communication (GSM) cells are identified by
  a 16-bit location area code (lac) and a 16-bit cell id (cid).

               Figure 9: Example GSM Cellular Measurement
















Thomson & Winterbottom       Standards Track                   [Page 20]

RFC 7105                  Location Measurements             January 2014


    <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>
          <sid>15892</sid><nid>4723</nid><baseid>12</baseid>
        </servingCell>
        <observedCell>
          <sid>15892</sid><nid>4723</nid><baseid>13</baseid>
        </observedCell>
      </cellular>
    </measurements>

  Code division multiple access (CDMA) cells are not identified by a
  PLMN; instead, these use a 15-bit system id (sid), a 16-bit network
  id (nid), and a 16-bit base station id (baseid).

              Figure 10: Example CDMA Cellular Measurement

  In general, a cellular Device will be attached to the cellular
  network, so the notion of a serving cell exists.  Cellular networks
  also provide overlap between neighboring 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 could 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 could
  report cells it can hear without identifying any particular cell as a
  serving cell.  An example of this is shown in Figure 11.

    <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







Thomson & Winterbottom       Standards Track                   [Page 21]

RFC 7105                  Location Measurements             January 2014


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

  A Global Navigation Satellite System (GNSS) uses 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.

  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.



Thomson & Winterbottom       Standards Track                   [Page 22]

RFC 7105                  Location Measurements             January 2014


     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 satellite system and includes measurement data
  for three satellites only.

    <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 Type 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.




Thomson & Winterbottom       Standards Track                   [Page 23]

RFC 7105                  Location Measurements             January 2014


  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 [GPS.ICD] and Galileo
  [Galileo.ICD].  Details for the registry are included in Section 9.1.

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



Thomson & Winterbottom       Standards Track                   [Page 24]

RFC 7105                  Location Measurements             January 2014


     knowledge of the carrier frequency of the satellite system.  This
     value permits the use of RMS error attributes, also measured in
     meters per second.

  codephase:  The observed code phase for the satellite signal,
     measured in milliseconds.  This is converted from the system-
     specific value of chips or wavelengths into a system-independent
     value.  Larger values indicate larger distances from satellite to
     receiver.  This value permits the use of RMS error attributes,
     also measured in milliseconds.

  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 meters.  This parameter MAY be omitted.

  cq:  An indication of the carrier quality.  Two attributes are
     included: "continuous" (which can be either "true" or "false") and
     "direct" (which can be either "direct" or "inverted").  This
     parameter MAY be omitted.

  adr:  The accumulated Doppler range, measured in meters.  This
     parameter MAY be omitted and is not useful unless multiple sets of
     GNSS measurements are provided or differential positioning is
     being performed.

  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 requests for GNSS measurements from multiple systems or
  signals.

5.6.  DSL Measurements

  Digital Subscriber Line (DSL) networks rely on a range of network
  technologies.  DSL deployments regularly require cooperation between
  multiple organizations.  These fall into two broad categories:
  infrastructure providers and Internet service providers (ISPs).  For
  the same end user, an infrastructure and Internet service can be
  provided by different entities.  Infrastructure providers manage the
  bulk of the physical infrastructure, including cabling.  End users



Thomson & Winterbottom       Standards Track                   [Page 25]

RFC 7105                  Location Measurements             January 2014


  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 and the parameters that are available.

  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, since the infrastructure provider could have 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.

5.6.1.  L2TP Measurements

  The Layer 2 Tunneling Protocol (L2TP) [RFC2661] 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 to which
  the Device is attached.  These data can be provided as a measurement
  that allows the infrastructure provider LIS to generate location
  information.







Thomson & Winterbottom       Standards Track                   [Page 26]

RFC 7105                  Location Measurements             January 2014


  The format of the AN, slot, and port identifiers is not defined in
  the RADIUS protocol.  The slot and port together identify a circuit
  on the AN, analogous to the circuit identifier in [RFC3046].  These
  items are provided directly, as they would be 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

5.6.3.  Ethernet VLAN Tag Measurements

  For Ethernet-based DSL access networks, the DSLAM or AN provides 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
  to which the Device is attached.  This information might be included
  in RADIUS requests that are proxied from the infrastructure provider
  to the ISP RADIUS server.












Thomson & Winterbottom       Standards Track                   [Page 27]

RFC 7105                  Location Measurements             January 2014


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.  Privacy Considerations

  Location-related measurement data can be as privacy sensitive as
  location information [RFC6280].

  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, measurement data MUST be protected with the same
  degree of protection as location information.  The confidentiality
  and authentication provided by Transport Layer Security (TLS) MUST be
  used in order to convey measurement data over HELD [RFC5985].  Other
  protocols MUST provide comparable guarantees.

6.1.  Measurement Data Privacy Model

  It is not necessary to distribute measurement data in the same
  fashion as location information.  Measurement data is less useful to
  location recipients than location information.  A simple distribution
  model is described in this document.








Thomson & Winterbottom       Standards Track                   [Page 28]

RFC 7105                  Location Measurements             January 2014


  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 act in the
  role of both Rule Maker and Location Server.

  A Device that provides location-related measurement data MUST only do
  so as explicitly authorized by a Rule Maker.  This depends on having
  an interface that allows Rule Makers (for instance, users or
  administrators) to control where and how measurement data is
  provided.

  No entity is permitted to redistribute measurement data.  The Device
  directs other entities regarding how measurement data is used and
  retained.

  The GEOPRIV model [RFC6280] protects the location of a Target using
  direction provided by a Rule Maker.  For the purposes of measurement
  data distribution, this model relies on the assumptions made in
  Section 3 of HELD [RFC5985].  These assumptions effectively declare
  the Device to be a proxy for both Target and Rule Maker.

6.2.  LIS Privacy Requirements

  A LIS MUST NOT reveal location-related measurement data to any other
  entity.  A LIS MUST NOT reveal 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.

6.3.  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
  explicitly requests a location URI.  By requesting a location URI,





Thomson & Winterbottom       Standards Track                   [Page 29]

RFC 7105                  Location Measurements             January 2014


  the Device grants permission for the LIS to use the measurement data
  in serving requests to that location URI.  The LIS cannot provide
  location recipients with measurement data, as defined in Section 6.1.

     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.  A
  LIS MUST NOT retain location-related measurement data in memory,
  storage, or logs beyond the time indicated in the "expires" attribute
  (Section 4.1.2).  A LIS MUST NOT retain measurement data if the
  "expires" attribute is absent.

6.4.  Measurement Data Provided by a Third Party

  An authorized third-party request for the location of a Device (see
  [RFC6155]) 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.  Either a
  third party MUST 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 7.2.1) before being used.

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

7.  Security Considerations

  The use of location-related measurement data has privacy
  considerations that are discussed in Section 6.

7.1.  Threat Model

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





Thomson & Winterbottom       Standards Track                   [Page 30]

RFC 7105                  Location Measurements             January 2014


  A Device that provides 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.

  Location-related measurement data describes the physical environment
  or network attachment of a Device.  A third-party adversary in the
  proximity of the Device might be able to alter the physical
  environment such that the Device provides measurement data that is
  controlled by the third party.  This might be used to indirectly
  control the location information that is derived from measurement
  data.

7.1.1.  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
  [RFC6155] allow 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
  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 unverified 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



Thomson & Winterbottom       Standards Track                   [Page 31]

RFC 7105                  Location Measurements             January 2014


  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.

7.1.2.  Extracting Network Topology Data

  Allowing requests with measurements might be used to collect
  information about network topology.

  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.

7.1.3.  Exposing Network Topology Data

  A Device could reveal information about a network to entities outside
  of that network if it provides location measurement data to a LIS
  that is outside of that network.  With the exception of GNSS
  measurements, the measurements in this document provide information
  about an access network that could reveal topology information to an
  unauthorized recipient.

  A Device MUST NOT provide information about network topology without
  a clear signal that the recipient is authorized.  A LIS that is
  discovered using DHCP as described in LIS discovery [RFC5986] can be
  considered to be authorized to receive information about the access
  network.




Thomson & Winterbottom       Standards Track                   [Page 32]

RFC 7105                  Location Measurements             January 2014


7.1.4.  Lying by Proxy

  Location information, which includes measurement data, is a function
  of its inputs.  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 causes 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 recipient 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.  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.

  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.

7.1.5.  Measurement Replay

  The values of some measured properties do not change over time for a
  single location.  The time invariance of network properties is often
  a direct 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.



Thomson & Winterbottom       Standards Track                   [Page 33]

RFC 7105                  Location Measurements             January 2014


  However, time-invariant properties allow 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 a 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.

7.1.6.  Environment Spoofing

  Some types of measurement data can be altered or influenced by a
  third party so that a Device unwittingly provides falsified data.  If
  it is possible for a third party to alter the measured phenomenon,
  then any location information that is derived from this data can be
  indirectly influenced.

  Altering the environment in this fashion might not require
  involvement with either a Device or LIS.  Measurement that is passive
  -- where the Device observes a signal or other phenomenon without
  direct interaction -- is most susceptible to alteration by third
  parties.

  Measurement of radio signal characteristics is especially vulnerable,
  since an adversary need only be in the general vicinity of the Device
  and be able to transmit a signal.  For instance, a GNSS spoofer is
  able to produce fake signals that claim to be transmitted by any
  satellite or set of satellites (see [GPS.SPOOF]).

  Measurements that require direct interaction increase the complexity
  of the attack.  For measurements relating to the communication
  medium, a third party cannot avoid direct interaction; they need only
  be on the communications path (that is, man in the middle).

  Even if the entity that is interacted with is authenticated, this
  does not provide any assurance about the integrity of measurement
  data.  For instance, the Device might authenticate the identity of a
  radio transmitter through the use of cryptographic means and obtain
  signal strength measurements for that transmitter.  Radio signal




Thomson & Winterbottom       Standards Track                   [Page 34]

RFC 7105                  Location Measurements             January 2014


  strength is trivial for an attacker to increase simply by receiving
  and amplifying the raw signal; it is not necessary for the attacker
  to be able to understand the signal content.

     Note: This particular "attack" is more often completely
     legitimate.  Radio repeaters are a commonplace mechanism used to
     increase radio coverage.

  Attacks that rely on altering the observed environment of a Device
  require countermeasures that affect the measurement process.  For
  radio signals, countermeasures could include the use of authenticated
  signals, or altered receiver design.  In general, countermeasures are
  highly specific to the individual measurement process.  An exhaustive
  discussion of these issues is left to the relevant literature for
  each measurement technology.

  A Device that provides measurement data is assumed to be responsible
  for applying appropriate countermeasures against this type of attack.

  Where a Device is the sole recipient of location information derived
  from measurement data, a LIS might choose to provide location
  information without any validation.  The responsibility for ensuring
  the veracity of the measurement data lies with the Device.

  Measurement data that is susceptible to this sort of influence SHOULD
  be treated as though it were produced by an untrusted Device for
  those cases where a location recipient might attribute the location
  information to the LIS.  GNSS measurements and radio signal strength
  measurements can be affected relatively cheaply, though almost all
  other measurement types can be affected with varying costs to an
  attacker, with the largest cost often being a requirement for
  physical access.  To the extent that it is feasible, measurement data
  SHOULD be subjected to the same validation as for other types of
  attacks that rely on measurement falsification.

     Note: Altered measurement data might be provided by a Device that
     has no knowledge of the alteration.  Thus, an otherwise trusted
     Device might still be an unreliable source of measurement data.

7.2.  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.







Thomson & Winterbottom       Standards Track                   [Page 35]

RFC 7105                  Location Measurements             January 2014


  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
      from which that location information was derived.

  This section goes into more detail on the different forms of
  validation in Sections 7.2.1, 7.2.2, and 7.2.3.  The impact of
  attributing location information to sources is discussed in more
  detail in Section 7.2.4.

  Any costs in validation are balanced against the degree of integrity
  desired from the resulting location information.

7.2.1.  Measurement Validation

  Recognizing 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.  When it's possible to gather the same measurement data from
  a trusted and independent source without undue expense, the LIS can
  use the trusted data in place of what the untrusted Device has sent.
  In cases where that is impractical, the untrusted data can provide
  hints that allow corroboration of the data (see Section 7.2.1.1).

  Measurement information might not contain any inherent indication
  that it is falsified.  In addition, 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.

7.2.1.1.  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 7.1.1.  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



Thomson & Winterbottom       Standards Track                   [Page 36]

RFC 7105                  Location Measurements             January 2014


  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 7.1.4), including attacks involving replay of measurement
  data (Section 7.1.5).  Validation also limits the amount of network
  topology information (Section 7.1.2) made available to Devices to
  that portion of the network topology to which they are directly
  attached.

  Measurement validation has no effect if the underlying environment is
  being altered (Section 7.1.6).

7.2.1.2.  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
  observer, it also makes the claims of a Device difficult to validate
  and easy 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.








Thomson & Winterbottom       Standards Track                   [Page 37]

RFC 7105                  Location Measurements             January 2014


  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 7.1.1) are largely
  ineffectual against a unique observer.

7.2.2.  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
  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.

7.2.2.1.  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 7.2.1.2).

  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.






Thomson & Winterbottom       Standards Track                   [Page 38]

RFC 7105                  Location Measurements             January 2014


7.2.2.2.  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 an uncertainty region
  with a radius of five kilometers.  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 be a boolean operation with
  only two possible outcomes: untrusted location information might be
  used entirely or not at all.  Alternatively, untrusted location
  information could be combined with trusted location information using
  different weightings, based on a value set in local policy.

7.2.3.  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
  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 measurement data from 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.



Thomson & Winterbottom       Standards Track                   [Page 39]

RFC 7105                  Location Measurements             January 2014


7.2.3.1.  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.

  The 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.  The applicability
  of each method is similar.

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

7.2.3.2.  Limitations

  The effectiveness of the validation method depends on the quality of
  the supporting observation: how hard it is for the entity performing
  the validation to obtain the data 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.

  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
  measurement imposes an acquisition cost.  Supporting observations
  contribute little or nothing toward the primary goal of determining
  the location of the Device.

7.2.4.  Attribution

  Lying by proxy (Section 7.1.4) 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.



Thomson & Winterbottom       Standards Track                   [Page 40]

RFC 7105                  Location Measurements             January 2014


  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 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 of 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
  labeled with the source of that data.

  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 entity or to
  both entities.  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].

  Attribution of information does nothing to address attacks that alter
  the observed parameters that are used in location determination
  (Section 7.1.6).






Thomson & Winterbottom       Standards Track                   [Page 41]

RFC 7105                  Location Measurements             January 2014


7.2.5.  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 7.1.2).

  Simply limiting the rate of requests from a single Device reduces the
  amount of data that a Device can acquire about network topology.  A
  LIS could also make observations about the movements of a Device.  A
  Device that is attempting to gather topology information is likely to
  be assigned a location that changes significantly between subsequent
  requests, possibly violating physical laws (or lower limits that
  might still be unlikely) with respect to speed and acceleration.

7.3.  An Unauthorized or Compromised LIS

  A compromised LIS, or a compromise in LIS discovery [RFC5986], could
  lead to an unauthorized entity obtaining measurement data.  This
  information could then be used or redistributed.  A Device MUST
  ensure that it authenticates a LIS, as described in Section 9 of
  [RFC5985].

  An entity that is able to acquire measurement data can, in addition
  to using those measurements to learn the location of a Device, also
  use that information for other purposes.  This information can be
  used to provide insight into network topology (Section 7.1.2).

  Measurement data might also be exploited in other ways.  For example,
  revealing the type of 802.11 transceiver that a Device uses could
  allow an attacker to use specific vulnerabilities to attack a Device.
  Similarly, revealing information about network elements could enable
  targeted attacks on that infrastructure.

8.  Measurement Schemas

  The schemas are broken up into their respective functions.  A base
  container schema into which all measurements are placed is defined,
  including the definition of a measurement request (Section 8.1).  A
  PIDF-LO extension is defined in a separate schema (Section 8.2).  A
  basic Types Schema contains common definitions, including the
  "rmsError" and "samples" attributes, plus types for IPv4, IPv6, and
  MAC addresses (Section 8.3).  Each of the specific measurement types
  is defined in a separate schema.








Thomson & Winterbottom       Standards Track                   [Page 42]

RFC 7105                  Location Measurements             January 2014


8.1.  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.rfc-editor.org/rfc/rfc7105.txt">
          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"
            type="lm:measurementRequestType"/>
    <xs:complexType name="measurementRequestType">
      <xs:complexContent>
        <xs:restriction base="xs:anyType">
          <xs:sequence>
            <xs:element ref="lm:measurement"
                        minOccurs="0" maxOccurs="unbounded"/>



Thomson & Winterbottom       Standards Track                   [Page 43]

RFC 7105                  Location Measurements             January 2014


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

    <xs:element name="measurement" type="lm:measurementType"/>
    <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>

    <!-- PIDF-LO extension for source -->
    <xs:element name="source" type="lm: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 Container Schema














Thomson & Winterbottom       Standards Track                   [Page 44]

RFC 7105                  Location Measurements             January 2014


8.2.  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.rfc-editor.org/rfc/rfc7105.txt">
          This schema defines an extension to PIDF-LO that indicates
          the type of measurement 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














Thomson & Winterbottom       Standards Track                   [Page 45]

RFC 7105                  Location Measurements             January 2014


8.3.  Base Types 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"
    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.rfc-editor.org/rfc/rfc7105.txt">
          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>





Thomson & Winterbottom       Standards Track                   [Page 46]

RFC 7105                  Location Measurements             January 2014


    <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">
      <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}:"/>




Thomson & Winterbottom       Standards Track                   [Page 47]

RFC 7105                  Location Measurements             January 2014


        <!-- 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 -->
        <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>

    <!-- MAC address (EUI-48) or EUI-64 address -->
    <xs:simpleType name="macAddressType">
      <xs:restriction base="xs:token">
        <xs:pattern
    value="[\da-fA-F]{2}(-[\da-fA-F]{2}){5}((-[\da-fA-F]{2}){2})?"/>
      </xs:restriction>
    </xs:simpleType>
  </xs:schema>

                            Base Types Schema

















Thomson & Winterbottom       Standards Track                   [Page 48]

RFC 7105                  Location Measurements             January 2014


8.4.  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.rfc-editor.org/rfc/rfc7105.txt">
          This schema defines a set of LLDP location measurements.
      </xs:documentation>
    </xs:annotation>

   <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>





Thomson & Winterbottom       Standards Track                   [Page 49]

RFC 7105                  Location Measurements             January 2014


    <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

8.5.  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">

    <xs:annotation>
      <xs:appinfo
          source="urn:ietf:params:xml:schema:geopriv:lm:dhcp">
      </xs:appinfo>
      <xs:documentation
          source="http://www.rfc-editor.org/rfc/rfc7105.txt">
          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"/>





Thomson & Winterbottom       Standards Track                   [Page 50]

RFC 7105                  Location Measurements             January 2014


            <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

8.6.  WiFi Measurement Schema

  <?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">
        802.11 location measurements
      </xs:appinfo>
      <xs:documentation
          source="http://www.rfc-editor.org/rfc/rfc7105.txt">
          This schema defines a basic set of 802.11 location
          measurements.
      </xs:documentation>
    </xs:annotation>








Thomson & Winterbottom       Standards Track                   [Page 51]

RFC 7105                  Location Measurements             January 2014


   <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:element name="ap" type="wifi:wifiType"
                        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">
          <xs:sequence>
            <xs:element name="bssid" type="wifi:bssidType"/>
            <xs:element name="ssid" type="wifi:ssidType"
                        minOccurs="0"/>
            <xs:element name="channel" type="xs:nonNegativeInteger"
                        minOccurs="0"/>
            <xs:element name="location" minOccurs="0"
                        type="xs:anyType"/>
            <xs:element name="type" type="wifi:networkType"
                        minOccurs="0"/>
            <xs:element name="regclass" type="wifi:regclassType"
                        minOccurs="0"/>
            <xs:element name="antenna" type="wifi:octetType"
                        minOccurs="0"/>
            <xs:element name="flightTime" minOccurs="0"
                        type="bt:nnDoubleWithRMSError"/>
            <xs:element name="apSignal" type="wifi:signalType"
                        minOccurs="0"/>
            <xs:element name="deviceSignal" type="wifi:signalType"
                        minOccurs="0"/>
            <xs:any namespace="##other" processContents="lax"
                    minOccurs="0" maxOccurs="unbounded"/>
          </xs:sequence>
          <xs:attribute name="serving" type="xs:boolean"
                        default="false"/>
          <xs:anyAttribute namespace="##any" processContents="lax"/>



Thomson & Winterbottom       Standards Track                   [Page 52]

RFC 7105                  Location Measurements             January 2014


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

    <xs:complexType name="bssidType">
      <xs:simpleContent>
        <xs:extension base="bt:macAddressType">
          <xs:attribute name="verified" type="xs:boolean"
                        default="false"/>
        </xs:extension>
      </xs:simpleContent>
    </xs:complexType>

    <!-- Note that this pattern does not prevent multibyte UTF-8
         sequences that result in an SSID longer than 32 octets. -->
    <xs:simpleType name="ssidType">
      <xs:restriction base="xs:token">
        <xs:pattern value="(\\[\da-fA-F]{2}|[^\\]){0,32}"/>
      </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="regclassType">
      <xs:simpleContent>
        <xs:extension base="wifi:octetType">
          <xs:attribute name="country">
            <xs:simpleType>
              <xs:restriction base="xs:token">
                <xs:pattern value="[A-Z]{2}[OIX]?"/>
              </xs:restriction>
            </xs:simpleType>
          </xs:attribute>
        </xs:extension>
      </xs:simpleContent>
    </xs:complexType>

    <xs:simpleType name="octetType">
      <xs:restriction base="xs:nonNegativeInteger">
        <xs:maxInclusive value="255"/>
      </xs:restriction>
    </xs:simpleType>





Thomson & Winterbottom       Standards Track                   [Page 53]

RFC 7105                  Location Measurements             January 2014


    <xs:complexType name="signalType">
      <xs:complexContent>
        <xs:restriction base="xs:anyType">
          <xs:sequence>
            <xs:element name="transmit" type="xs:double"
                        minOccurs="0"/>
            <xs:element name="gain" type="xs:double" minOccurs="0"/>
            <xs:element name="rcpi" type="wifi:rssiType"
                        minOccurs="0"/>
            <xs:element name="rsni" type="bt:doubleWithRMSError"
                        minOccurs="0"/>
            <xs:any namespace="##other" processContents="lax"
                    minOccurs="0" maxOccurs="unbounded"/>
          </xs:sequence>
        </xs:restriction>
      </xs:complexContent>
    </xs:complexType>

    <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"/>
    <xs:element name="parameter" type="wifi:parameterType"/>

    <xs:complexType name="parameterType">
      <xs:simpleContent>
        <xs:extension base="xs:QName">
          <xs:attribute name="context" use="optional">
            <xs:simpleType>
              <xs:restriction base="xs:token">
                <xs:enumeration value="ap"/>
                <xs:enumeration value="device"/>
              </xs:restriction>
            </xs:simpleType>
          </xs:attribute>
        </xs:extension>
      </xs:simpleContent>
    </xs:complexType>
  </xs:schema>

                         WiFi Measurement Schema




Thomson & Winterbottom       Standards Track                   [Page 54]

RFC 7105                  Location Measurements             January 2014


8.7.  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.rfc-editor.org/rfc/rfc7105.txt">
          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">
          <xs:choice>
            <xs:sequence>
              <xs:element name="mcc" type="cell:mccType"/>
              <xs:element name="mnc" type="cell:mncType"/>
              <xs:choice>
                <xs:sequence>
                  <xs:choice>



Thomson & Winterbottom       Standards Track                   [Page 55]

RFC 7105                  Location Measurements             January 2014


                    <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="sid" type="cell:cellIdType"/>
              <xs:element name="nid" 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="268435455"/> <!-- 2^28 (eucid) -->
      </xs:restriction>
    </xs:simpleType>

    <!-- 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"/>



Thomson & Winterbottom       Standards Track                   [Page 56]

RFC 7105                  Location Measurements             January 2014


        <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

8.8.  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.rfc-editor.org/rfc/rfc7105.txt">
          This schema defines a set of GNSS location measurements.
      </xs:documentation>
    </xs:annotation>








Thomson & Winterbottom       Standards Track                   [Page 57]

RFC 7105                  Location Measurements             January 2014


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




Thomson & Winterbottom       Standards Track                   [Page 58]

RFC 7105                  Location Measurements             January 2014


    <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

8.9.  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.rfc-editor.org/rfc/rfc7105.txt">
          This schema defines a basic set of DSL location measurements.
      </xs:documentation>
    </xs:annotation>










Thomson & Winterbottom       Standards Track                   [Page 59]

RFC 7105                  Location Measurements             January 2014


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

    <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>





Thomson & Winterbottom       Standards Track                   [Page 60]

RFC 7105                  Location Measurements             January 2014


    <xs:simpleType name="vlanIDType">
      <xs:restriction base="xs:nonNegativeInteger">
        <xs:maxInclusive value="4095"/>
      </xs:restriction>
    </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

9.  IANA Considerations

  This section creates a registry for GNSS types (Section 5.5) and
  registers the namespaces and schemas defined in Section 8.

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 of the GNSS

  Brief Description:  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

  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)




Thomson & Winterbottom       Standards Track                   [Page 61]

RFC 7105                  Location Measurements             January 2014


  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
     ([email protected]), Martin Thomson ([email protected]).

     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 Source for PIDF-LO</title>
        </head>





Thomson & Winterbottom       Standards Track                   [Page 62]

RFC 7105                  Location Measurements             January 2014


        <body>
          <h1>Namespace for Location Measurement Source</h1>
          <h2>urn:ietf:params:xml:ns:pidf:geopriv10:lmsrc</h2>
          <p>See <a href="http://www.rfc-editor.org/rfc/rfc7105.txt">
             RFC 7105</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
     ([email protected]), Martin Thomson ([email protected]).

     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>
          <p>See <a href="http://www.rfc-editor.org/rfc/rfc7105.txt">
             RFC 7105</a>.</p>
        </body>
      </html>
        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



Thomson & Winterbottom       Standards Track                   [Page 63]

RFC 7105                  Location Measurements             January 2014


     Registrant Contact: IETF, GEOPRIV working group
     ([email protected]), Martin Thomson ([email protected]).

     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>
          <p>See <a href="http://www.rfc-editor.org/rfc/rfc7105.txt">
             RFC 7105</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
     ([email protected]), Martin Thomson ([email protected]).

     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>LLDP Measurement Set</title>
        </head>







Thomson & Winterbottom       Standards Track                   [Page 64]

RFC 7105                  Location Measurements             January 2014


        <body>
          <h1>Namespace for LLDP Measurement Set</h1>
          <h2>urn:ietf:params:xml:ns:geopriv:lm:lldp</h2>
          <p>See <a href="http://www.rfc-editor.org/rfc/rfc7105.txt">
             RFC 7105</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
     ([email protected]), Martin Thomson ([email protected]).

     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>
          <p>See <a href="http://www.rfc-editor.org/rfc/rfc7105.txt">
             RFC 7105</a>.</p>
        </body>
      </html>
        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



Thomson & Winterbottom       Standards Track                   [Page 65]

RFC 7105                  Location Measurements             January 2014


     Registrant Contact: IETF, GEOPRIV working group
     ([email protected]), Martin Thomson ([email protected]).

     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>
          <p>See <a href="http://www.rfc-editor.org/rfc/rfc7105.txt">
             RFC 7105</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
     ([email protected]), Martin Thomson ([email protected]).

     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>Cellular Measurement Set</title>
        </head>







Thomson & Winterbottom       Standards Track                   [Page 66]

RFC 7105                  Location Measurements             January 2014


        <body>
          <h1>Namespace for Cellular Measurement Set</h1>
          <h2>urn:ietf:params:xml:ns:geopriv:lm:cell</h2>
          <p>See <a href="http://www.rfc-editor.org/rfc/rfc7105.txt">
             RFC 7105</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
     ([email protected]), Martin Thomson ([email protected]).

     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>
          <p>See <a href="http://www.rfc-editor.org/rfc/rfc7105.txt">
             RFC 7105</a>.</p>
        </body>
      </html>
        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



Thomson & Winterbottom       Standards Track                   [Page 67]

RFC 7105                  Location Measurements             January 2014


     Registrant Contact: IETF, GEOPRIV working group
     ([email protected]), Martin Thomson ([email protected]).

     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>
          <p>See <a href="http://www.rfc-editor.org/rfc/rfc7105.txt">
             RFC 7105</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 ([email protected]),
     Martin Thomson ([email protected]).

  Schema:  The XML for this schema can be found in Section 8.2 of this
     document.

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:geopriv:lm

  Registrant Contact:  IETF, GEOPRIV working group ([email protected]),
     Martin Thomson ([email protected]).

  Schema:  The XML for this schema can be found in Section 8.1 of this
     document.




Thomson & Winterbottom       Standards Track                   [Page 68]

RFC 7105                  Location Measurements             January 2014


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:geopriv:lm:basetypes

  Registrant Contact:  IETF, GEOPRIV working group ([email protected]),
     Martin Thomson ([email protected]).

  Schema:  The XML for this schema can be found in Section 8.3 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:geopriv:lm:lldp

  Registrant Contact:  IETF, GEOPRIV working group ([email protected]),
     Martin Thomson ([email protected]).

  Schema:  The XML for this schema can be found in Section 8.4 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:geopriv:lm:dhcp

  Registrant Contact:  IETF, GEOPRIV working group ([email protected]),
     Martin Thomson ([email protected]).

  Schema:  The XML for this schema can be found in Section 8.5 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:geopriv:lm:wifi

  Registrant Contact:  IETF, GEOPRIV working group ([email protected]),
     Martin Thomson ([email protected]).



Thomson & Winterbottom       Standards Track                   [Page 69]

RFC 7105                  Location Measurements             January 2014


  Schema:  The XML for this schema can be found in Section 8.6 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:geopriv:lm:cell

  Registrant Contact:  IETF, GEOPRIV working group ([email protected]),
     Martin Thomson ([email protected]).

  Schema:  The XML for this schema can be found in Section 8.7 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:geopriv:lm:gnss

  Registrant Contact:  IETF, GEOPRIV working group ([email protected]),
     Martin Thomson ([email protected]).

  Schema:  The XML for this schema can be found in Section 8.8 of this
     document.

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:geopriv:lm:dsl

  Registrant Contact:  IETF, GEOPRIV working group ([email protected]),
     Martin Thomson ([email protected]).

  Schema:  The XML for this schema can be found in Section 8.9 of this
     document.

10.  Acknowledgements

  Thanks go to Simon Cox for his comments relating to terminology; his
  comments have helped ensure that this document is aligned with
  ongoing work in the Open Geospatial Consortium (OGC).  Thanks to Neil
  Harper for his review and comments on the GNSS sections of this



Thomson & Winterbottom       Standards Track                   [Page 70]

RFC 7105                  Location Measurements             January 2014


  document.  Thanks to Noor-E-Gagan Singh, Gabor Bajko, Russell Priebe,
  and Khalid Al-Mufti for their significant input to, and suggestions
  for, improving the 802.11 measurements.  Thanks to Cullen Jennings
  for feedback and suggestions.  Bernard Aboba provided review and
  feedback on a range of measurement data definitions.  Mary Barnes and
  Geoff Thompson provided a review and corrections.  David Waitzman and
  John Bressler both noted shortcomings with 802.11 measurements.
  Keith Drage and Darren Pawson provided expert LTE knowledge.

11.  References

11.1.  Normative References

  [ASCII]    ANSI, "US-ASCII. Coded Character Set - 7-Bit American
             Standard Code for Information Interchange. Standard ANSI
             X3.4-1986", 1986.

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

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

  [IANA.enterprise]
             IANA, "Private Enterprise Numbers", 2014,
             <http://www.iana.org/assignments/enterprise-numbers>.

  [IEEE.80211]
             IEEE, "Wireless LAN Medium Access Control (MAC) and
             Physical Layer (PHY) Specifications", IEEE
             Std 802.11-2012, March 2012.

  [IEEE.8021AB]
             IEEE, "IEEE Standard for Local and Metropolitan Area
             Networks, Station and Media Access Control Connectivity
             Discovery", IEEE Std 802.1AB-2009, September 2009.

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

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

  [RFC3315]  Droms, R., Bound, J., Volz, B., Lemon, T., Perkins, C.,
             and M. Carney, "Dynamic Host Configuration Protocol for
             IPv6 (DHCPv6)", RFC 3315, July 2003.




Thomson & Winterbottom       Standards Track                   [Page 71]

RFC 7105                  Location Measurements             January 2014


  [RFC3629]  Yergeau, F., "UTF-8, a transformation format of
             ISO 10646", STD 63, RFC 3629, November 2003.

  [RFC3986]  Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
             Resource Identifier (URI): Generic Syntax", STD 66,
             RFC 3986, January 2005.

  [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.

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

  [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.

  [RFC5952]  Kawamura, S. and M. Kawashima, "A Recommendation for IPv6
             Address Text Representation", RFC 5952, August 2010.

  [RFC5985]  Barnes, M., "HTTP-Enabled Location Delivery (HELD)",
             RFC 5985, September 2010.

  [RFC5986]  Thomson, M. and J. Winterbottom, "Discovering the Local
             Location Information Server (LIS)", RFC 5986,
             September 2010.

  [TIA-2000.5]
             TIA/EIA, "Upper Layer (Layer 3) Signaling Standard for
             cdma2000(R) Spread Spectrum Systems", TR-45.5 / TSG-C
             TIA-2000.5-E / C.S0005-E v1.0, September 2009.







Thomson & Winterbottom       Standards Track                   [Page 72]

RFC 7105                  Location Measurements             January 2014


  [TS.3GPP.23.003]
             3GPP, "Numbering, addressing and identification", 3GPP TS
             23.003 12.0.0, September 2013,
             <http://www.3gpp.org/ftp/Specs/html-info/23003.htm>.

11.2.  Informative References

  [ANSI-TIA-1057]
             ANSI/TIA, "Link Layer Discovery Protocol for Media
             Endpoint Devices", TIA 1057, April 2006.

  [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.SPOOF]
             Scott, L., "Anti-Spoofing and Authenticated Signal
             Architectures for Civil Navigation Signals", ION-GNSS
             Portland, Oregon, 2003.

  [HARPER]   Harper, N., "Server-side GPS and Assisted-GPS in Java",
             December 2009.

  [RFC2661]  Townsley, W., Valencia, A., Rubens, A., Pall, G., Zorn,
             G., and B. Palter, "Layer Two Tunneling Protocol "L2TP"",
             RFC 2661, August 1999.

  [RFC2865]  Rigney, C., Willens, S., Rubens, A., and W. Simpson,
             "Remote Authentication Dial In User Service (RADIUS)",
             RFC 2865, June 2000.

  [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.

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

  [RFC6155]  Winterbottom, J., Thomson, M., Tschofenig, H., and R.
             Barnes, "Use of Device Identity in HTTP-Enabled Location
             Delivery (HELD)", RFC 6155, March 2011.



Thomson & Winterbottom       Standards Track                   [Page 73]

RFC 7105                  Location Measurements             January 2014


  [RFC6280]  Barnes, R., Lepinski, M., Cooper, A., Morris, J.,
             Tschofenig, H., and H. Schulzrinne, "An Architecture for
             Location and Location Privacy in Internet Applications",
             BCP 160, RFC 6280, July 2011.

Authors' Addresses

  Martin Thomson
  Mozilla
  Suite 300
  650 Castro Street
  Mountain View, CA  94041
  US

  EMail: [email protected]


  James Winterbottom
  Unaffiliated
  AU

  EMail: [email protected]





























Thomson & Winterbottom       Standards Track                   [Page 74]