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Versions: (draft-gellens-ecrit-car-crash) 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 RFC 8148

ECRIT                                                         R. Gellens
Internet-Draft                                Core Technology Consulting
Intended status: Standards Track                                B. Rosen
Expires: July 23, 2017                                     NeuStar, Inc.
                                                           H. Tschofenig
                                                              Individual
                                                        January 19, 2017


           Next-Generation Vehicle-Initiated Emergency Calls
                   draft-ietf-ecrit-car-crash-23.txt

Abstract

   This document describes how to use IP-based emergency services
   mechanisms to support the next generation of emergency calls placed
   by vehicles (automatically in the event of a crash or serious
   incident, or manually invoked by a vehicle occupant) and conveying
   vehicle, sensor, and location data related to the crash or incident.
   Such calls are often referred to as "Automatic Crash Notification"
   (ACN), or "Advanced Automatic Crash Notification" (AACN), even in the
   case of manual trigger.  The "Advanced" qualifier refers to the
   ability to carry a richer set of data.

   This document also registers a MIME media type and Emergency Call
   Additional Data Block for the vehicle, sensor, and location data
   (often referred to as "crash data" even though there is not
   necessarily a crash) and a SIP INFO package to enable carrying this
   and related data in SIP INFO requests.  An external specification for
   the data format, contents, and structure are referenced in this
   document.

   This document reuses the technical aspects of next-generation pan-
   European eCall (a mandated and standardized system for emergency
   calls by in-vehicle systems within Europe and other regions).
   However, this document specifies use of a different set of vehicle
   (crash) data, specifically, the Vehicle Emergency Data Set (VEDS)
   rather than the eCall Minimum Set of Data (MSD).  This document is an
   extension of the IETF eCall document, with the primary differences
   being that this document makes the MSD data set optional and VEDS
   mandatory, and adds attribute values to the metadata/control object
   to permit greater functionality.  This document registers a new SIP
   INFO package (identical to that registered for eCall but with the
   addition of the VEDS MIME type).  This document also describes legacy
   (circuit-switched) ACN systems and their migration to next-generation
   emergency calling, to provide background information and context.





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Status of This Memo

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

   Internet-Drafts are working documents of the Internet Engineering
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   Internet-Drafts are draft documents valid for a maximum of six months
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   This Internet-Draft will expire on July 23, 2017.

Copyright Notice

   Copyright (c) 2017 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
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   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   4
   3.  Document Scope  . . . . . . . . . . . . . . . . . . . . . . .   7
   4.  Overview of Legacy Deployment Models  . . . . . . . . . . . .   8
   5.  Migration to Next-Generation  . . . . . . . . . . . . . . . .   9
   6.  Vehicle Data  . . . . . . . . . . . . . . . . . . . . . . . .  12
   7.  Data Transport  . . . . . . . . . . . . . . . . . . . . . . .  13
   8.  Call Setup  . . . . . . . . . . . . . . . . . . . . . . . . .  15
   9.  New Metadata/Control Values . . . . . . . . . . . . . . . . .  16
     9.1.  New values for the 'action' attribute'  . . . . . . . . .  17
     9.2.  Request Example . . . . . . . . . . . . . . . . . . . . .  18
     9.3.  The <ack> element . . . . . . . . . . . . . . . . . . . .  19
     9.4.  The <capabilities> element  . . . . . . . . . . . . . . .  20
   10. Test Calls  . . . . . . . . . . . . . . . . . . . . . . . . .  21



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   11. Example . . . . . . . . . . . . . . . . . . . . . . . . . . .  22
   12. Security Considerations . . . . . . . . . . . . . . . . . . .  27
   13. Privacy Considerations  . . . . . . . . . . . . . . . . . . .  28
   14. IANA Considerations . . . . . . . . . . . . . . . . . . . . .  28
     14.1.  MIME Media Type Registration for
            'application/EmergencyCall.VEDS+xml' . . . . . . . . . .  28
     14.2.  Registration of the 'VEDS' entry in the Emergency Call
            Data Types registry  . . . . . . . . . . . . . . . . . .  30
     14.3.  New Action Values  . . . . . . . . . . . . . . . . . . .  30
     14.4.  Emergency Call Static Message Registry . . . . . . . . .  30
     14.5.  Emergency Call Vehicle Lamp ID Registry  . . . . . . . .  31
     14.6.  Emergency Call Vehicle Camera ID Registry  . . . . . . .  32
     14.7.  The emergencyCallData.eCall.VEDS SIP INFO package  . . .  33
   15. Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  36
   16. Changes from Previous Versions  . . . . . . . . . . . . . . .  37
     16.1.  Changes from draft-ietf-18 to draft-ietf-19  . . . . . .  37
     16.2.  Changes from draft-ietf-17 to draft-ietf-18  . . . . . .  37
     16.3.  Changes from draft-ietf-16 to draft-ietf-17  . . . . . .  37
     16.4.  Changes from draft-ietf-14 to draft-ietf-15  . . . . . .  37
     16.5.  Changes from draft-ietf-13 to draft-ietf-14  . . . . . .  37
     16.6.  Changes from draft-ietf-11 to draft-ietf-13  . . . . . .  37
     16.7.  Changes from draft-ietf-10 to draft-ietf-11  . . . . . .  37
     16.8.  Changes from draft-ietf-09 to draft-ietf-10  . . . . . .  38
     16.9.  Changes from draft-ietf-08 to draft-ietf-09  . . . . . .  38
     16.10. Changes from draft-ietf-07 to draft-ietf-08  . . . . . .  38
     16.11. Changes from draft-ietf-06 to draft-ietf-07  . . . . . .  38
     16.12. Changes from draft-ietf-05 to draft-ietf-06  . . . . . .  38
     16.13. Changes from draft-ietf-04 to draft-ietf-05  . . . . . .  38
     16.14. Changes from draft-ietf-03 to draft-ietf-04  . . . . . .  38
     16.15. Changes from draft-ietf-02 to draft-ietf-03  . . . . . .  39
     16.16. Changes from draft-ietf-01 to draft-ietf-02  . . . . . .  39
     16.17. Changes from draft-ietf-00 to draft-ietf-01  . . . . . .  39
     16.18. Changes from draft-gellens-02 to draft-ietf-00 . . . . .  39
     16.19. Changes from draft-gellens-01 to -02 . . . . . . . . . .  39
     16.20. Changes from draft-gellens-00 to -01 . . . . . . . . . .  39
   17. References  . . . . . . . . . . . . . . . . . . . . . . . . .  40
     17.1.  Normative References . . . . . . . . . . . . . . . . . .  40
     17.2.  Informative references . . . . . . . . . . . . . . . . .  41
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  42

1.  Terminology

   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].

   This document re-uses terminology defined in Section 3 of [RFC5012].




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   Additionally, we use the following abbreviations:

   +--------+----------------------------------------------------------+
   | Term   | Expansion                                                |
   +--------+----------------------------------------------------------+
   | 3GPP   | 3rd Generation Partnership Project                       |
   | AACN   | Advanced Automatic Crash Notification                    |
   | ACN    | Automatic Crash Notification                             |
   | APCO   | Association of Public-Safety Communications Officials    |
   | EENA   | European Emergency Number Association                    |
   | ESInet | Emergency Services IP network                            |
   | GNSS   | Global Navigation Satellite System (which includes       |
   |        | various systems such as the Global Positioning System or |
   |        | GPS)                                                     |
   | IVS    | In-Vehicle System                                        |
   | MNO    | Mobile Network Operator                                  |
   | MSD    | eCall Minimum Set of Data                                |
   | NENA   | National Emergency Number Association                    |
   | NG     | Next-Generation                                          |
   | POTS   | Plain Old Telephone Service (normal, circuit-switched    |
   |        | voice calls)                                             |
   | PSAP   | Public Safety Answering Point                            |
   | TSP    | Telematics Service Provider                              |
   | VEDS   | Vehicle Emergency Data Set                               |
   +--------+----------------------------------------------------------+

   Because the endpoints of a Next-Generation ACN call are a PSAP and an
   IVS or TSP, to avoid receptively writing "IVS or TSP", the term "IVS"
   is used to represent either an IVS or TSP when discussing signaling
   behavior (e.g., sending VEDS data, sending a SIP INVITE request,
   receiving a SIP INFO request, etc.).

2.  Introduction

   Emergency calls made by in-vehicle systems (e.g., automatically in
   the event of a crash or serious incident or manually by a vehicle
   occupant) assist in significantly reducing road deaths and injuries
   by allowing emergency services to respond quickly and appropriately
   to the specifics of the incident, often with better location
   accuracy.

   Drivers often have a poor location awareness, especially outside of
   major cities, at night and when away from home (especially abroad).
   In the most crucial cases, the victim(s) might not be able to call
   because they have been injured or trapped.

   For more than two decades, some vehicles have been equipped with
   telematics systems which, among other features, place an emergency



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   call automatically in the event of a crash or manually in response to
   an emergency call button.  Such systems generally have on-board
   location determination systems that make use of satellite-based
   positioning technology, inertial sensors, gyroscopes, etc., which can
   provide an accurate position for the vehicle.  Such built-in systems
   can take advantage of the benefits of being integrated into a
   vehicle, such as more power capacity, ability to have larger or
   specialized antenna, ability to be engineered to avoid or minimise
   degradation by vehicle glass coatings, interference from other
   vehicle systems, etc.  Thus, the PSAP can be provided with a good
   estimate of where the vehicle is during an emergency.  Vehicle
   manufacturers are increasingly adopting such systems, both for the
   safety benefits and for the additional features and services they
   enable (e.g., remote engine diagnostics, remote door unlock, stolen
   vehicle tracking and disabling, etc.).

   The general term for such systems is Automatic Crash Notification
   (ACN) or "Advanced Automatic Crash Notification" (AACN).  "ACN" is
   used in this document as a general term.  ACN systems transmit some
   amount of data specific to the incident, referred to generally as
   "crash data" (the term is commonly used even though there might not
   have been a crash).  While different systems transmit different
   amounts of crash data, standardized formats, structures, and
   mechanisms are needed to provide interoperability among systems and
   PSAPs.

   As of the date of this document, currently deployed in-vehicle
   telematics systems are circuit-switched and lack a standards-based
   ability to convey crash data directly to the PSAP (generally relying
   on either a human advisor or an automated text-to-speech system to
   provide the PSAP call taker with some crash data orally, or in some
   cases via a proprietary mechanism).  In most cases, the PSAP call
   taker needs to first realize that the call is related to a vehicle
   incident, and then listen to the data and transcribe it.  Circuit-
   switched ACN systems are referred to here as CS-ACN.

   The transition to next-generation calling in general, and for
   emergency calling in particular, provides an opportunity to vastly
   improve the scope, breadth, reliability and usefulness of crash data
   during an emergency by allowing a standardized set to be transmitted
   during call set-up; to be automatically processed by the PSAP and
   made available to the call taker in an integrated, automated way; as
   well as provide the ability for a PSAP call taker to request that a
   vehicle take certain actions, such as flashing lights or unlocking
   doors.  In addition, vehicle manufacturers are provided an
   opportunity to take advantage of the same standardized mechanisms for
   data transmission and request processing for internal use if they
   wish (such as telemetry between the vehicle and a service center for



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   both emergency and non-emergency uses, including location-based
   services, multi-media entertainment systems, remote door unlocking,
   remote diagnostics, and road-side assistance applications).

   Next-generation ACN provides an opportunity for such calls to be
   recognized and processed as such during call set-up, and routed to an
   equipped PSAP where the vehicle data is available to assist the call
   taker in assessing and responding to the situation.  Next-generation
   (IP-based) ACN systems are referred to here as NG-ACN.

   An ACN call can be initiated by a vehicle occupant or automatically
   initiated by vehicle systems in the event of a serious incident.
   (The "A" in "ACN" does stand for "Automatic," but the term is broadly
   used to refer to the class of calls that are placed by an in-vehicle
   system (IVS) or Telematics Service Providers (TSP) and that carry
   incident-related data as well as voice.)  Automatically triggered
   calls indicate a car crash or some other serious incident (e.g., a
   fire).  Manually triggered calls include reports of observed crashes
   or serious hazards (such as impaired drivers or roadway debris).

   The Association of Public-Safety Communications Officials (APCO) and
   the National Emergency Number Association (NENA) have jointly
   developed a standardized set of incident-related vehicle data for ACN
   use, called the Vehicle Emergency Data Set (VEDS) [VEDS].  Such data
   is often referred to as crash data although it is applicable in
   incidents other than crashes.

   This document describes how the IETF mechanisms for IP-based
   emergency calls are used to provide the realization of next-
   generation ACN.  Although this specification is designed with the
   requirements for North America ACN in mind (and both APCO and NENA
   are based in the U.S.), it is specified generically such that the
   technology can be re-used or extended to suit requirements in other
   regions.

   This document reuses the technical aspects of next-generation pan-
   European eCall (a mandated and standardized system for emergency
   calls by in-vehicle systems within Europe), as described in
   [I-D.ietf-ecrit-ecall].  However, this document specifies use of a
   different set of vehicle (crash) data, specifically, the Vehicle
   Emergency Data Set (VEDS) rather than the eCall Minimum Set of Data
   (MSD).  This document is an extension of [I-D.ietf-ecrit-ecall], with
   the differences being that this document makes the MSD data set
   optional and VEDS mandatory, and adds new attribute values to the
   metadata/control object defined in that document.  This document also
   registers a new SIP INFO package (identical to that defined in
   [I-D.ietf-ecrit-ecall] with the addition of the VEDS MIME type).




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   This document registers the 'application/EmergencyCallData.VEDS+xml'
   MIME media type, registers the 'VEDS' entry in the Emergency Call
   Data Types registry, and registers a SIP INFO package to enable
   carrying this and related data in SIP INFO requests.

   Section 6 introduces VEDS.  Section 7 describes how VEDS data and
   metadata/control blocks are transported within NG-ACN calls.
   Section 8 describes how such calls are placed.

   These mechanisms are used to place emergency calls that are
   identifiable as ACN calls and that carry standardized crash data in
   an interoperable way.

   Calls by in-vehicle systems are placed using cellular networks, which
   might ignore location information sent by an originating device in an
   emergency call INVITE, instead substituting their own location
   information (often determined in cooperation with the originating
   device).  Standardized crash data structures often include location
   as determined by the IVS.  A benefit of this is that it allows the
   PSAP to see both the location as determined by the cellular network
   (often in cooperation with the originating device) and the location
   as determined by the IVS.

   This specification inherits the ability to utilize test call
   functionality from Section 15 of [RFC6881].

3.  Document Scope

   This document is focused on how an ACN emergency call is setup and
   incident-related data (including vehicle, sensor, and location data)
   is transmitted to the PSAP using IETF specifications.  For the direct
   model, this is the end-to-end description (between the vehicle and
   the PSAP).  For the TSP model, this describes the call leg between
   the TSP and the PSAP, leaving the call leg between the vehicle and
   the TSP up to the entities involved (i.e., IVS and TSP vendors) who
   are then free to use the same mechanism as for the other leg or not.

   Note that Europe has a mandated and standardized system for emergency
   calls by in-vehicle systems.  This pan-European system is known as
   "eCall" and is the subject of a separate document,
   [I-D.ietf-ecrit-ecall], which this document builds on.  Vehicles
   designed to operate in multiple regions might need to support eCall
   as well as NG-ACN as described here.  A vehicle IVS might determine
   whether to use eCall or ACN by first determining the region or
   country in which it is located (e.g., from a GNSS location estimate
   and/or identity of or information from an MNO).  If other regions
   adopt other data formats, a multi-region vehicle might need to
   support those as well.  This document adopts the call set-up and



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   other technical aspects of [I-D.ietf-ecrit-ecall], which uses
   [RFC7852]; this makes it straightforward to use a different data set
   while keeping other technical aspects unchanged.  Hence, both NG-
   eCall and the NG-ACN mechanism described here are compatible,
   differing primarily in the specific data block that is sent (the
   eCall MSD in the case of NG-eCall, and the APCO/NENA VEDS used in
   this document), and some additions to the metadata/control data
   block.  If other regions adopt their own vehicle data sets, this can
   be similarly accomodated without changing other technical aspects.
   Note that any additional data formats require a new SIP INFO package
   to permit transport within SIP INFO requests.

4.  Overview of Legacy Deployment Models

   Legacy (circuit-switched) systems for placing emergency calls by in-
   vehicle systems generally have some ability to convey at least
   location and in some cases telematics data to the PSAP.  Most such
   systems use one of three architectural models, which are described
   here as: "Telematics Service Provider" (TSP), "direct", and "paired".
   These three models are illustrated below.

   In the TSP model, both emergency and non-emergency calls are placed
   to a Telematics Service Provider (TSP); a proprietary technique is
   used for data transfer (such as a proprietary in-band modem) between
   the TSP and the vehicle.

   In an emergency, generally the TSP call taker bridges in the PSAP and
   communicates location, crash data (such as impact severity and trauma
   prediction), and other data (such as the vehicle description) to the
   PSAP call taker verbally (in some cases, a proprietary out-of-band
   interface is used).  Since the TSP knows the location of the vehicle
   (from on-board GNSS and sensors), location-based routing is usually
   used to route to the appropriate PSAP.  In some cases, the TSP is
   able to transmit location automatically, using similar techniques as
   for wireless calls.  Typically, a three-way voice call is established
   between the vehicle, the TSP, and the PSAP, allowing communication
   between the PSAP call taker, the TSP call taker, and the vehicle
   occupants (who might be unconscious).

      ///----\\\  proprietary  +------+ 911 trunk or POTS  +------+
     ||| IVS |||-------------->+ TSP  +------------------->+ PSAP |
      \\\----///  crash data   +------+ location via trunk +------+


                        Figure 1: Legacy TSP Model.

   In the paired model, the IVS uses a local link (typically Bluetooth
   [Bluetooth]) with a previously-paired handset to establish an



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   emergency call with the PSAP (by dialing a standard emergency number;
   9-1-1 in North America), and then communicates location data to the
   PSAP via text-to-speech; crash data might or might not be conveyed
   also using text-to-speech.  Some such systems use an automated voice
   prompt menu for the PSAP call taker (e.g., "this is an automatic
   emergency call from a vehicle; press 1 to open a voice path to the
   vehicle; press 2 to hear the location read out") to allow the call
   taker to request location data via text-to-speech.

                   +---+
      ///----\\\   | H |   911/etc voice call via handset   +------+
     ||| IVS |||-->| S +----------------------------------->+ PSAP |
      \\\----///   +---+   location via text-to-speech      +------+


                       Figure 2: Legacy Paired Model

   In the direct model, the IVS directly places an emergency call with
   the PSAP by dialing a standard emergency number (9-1-1 in North
   America).  Such systems might communicate location data to the PSAP
   via text-to-speech; crash data might or might not be conveyed using
   text-to-speech.  Some such systems use an automated voice prompt menu
   (e.g., "this is an automatic emergency call from a vehicle; press 1
   to open a voice path to the vehicle; press 2 to hear the location
   read out") to allow the call taker to request location data via text-
   to-speech.

      ///----\\\      911/etc voice call via IVS          +------+
     ||| IVS  |||---------------------------------------->+ PSAP |
      \\\----///     location via text-to-speech          +------+


                       Figure 3: Legacy Direct Model

5.  Migration to Next-Generation

   Migration of emergency calls placed by in-vehicle systems to next-
   generation (all-IP) technology per this document provides a
   standardized mechanism to identify such calls and to convey crash
   data with the call setup, as well as enabling additional
   communications modalities and enhanced functionality.  This allows
   ACN calls and crash data to be automatically processed by the PSAP
   and made available to the call taker in an integrated, automated way.
   Because the crash data is carried in the initial SIP INVITE (per
   [RFC7852]) the PSAP can present it to the call taker simultaneously
   with the appearance of the call.  The PSAP can also process the data
   to take other actions (e.g., if multiple calls from the same location
   arrive when the PSAP is busy and a subset of them are NG-ACN calls, a



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   PSAP might choose to store the information and reject the calls,
   since the IVS will receive confirmation that the information has been
   successfully received; a PSAP could also choose to include a message
   stating that it is aware of the incident and responders are on the
   way; a PSAP could call the vehicle back when a call taker is
   available).

   The migration of origination devices and networks, PSAPs, emergency
   services networks, and other telephony environments to next-
   generation provides enhanced interoperability and functionality,
   especially for emergency calls carrying additional data such as
   vehicle crash data.  (In the U.S., a network specifically for
   emergency responders is being developed.  This network, FirstNet,
   will be next-generation from the start, enhancing the ability for
   data exchange between PSAPs and responders.)

   NG-ACN calls can be recognized as originating from a vehicle, routed
   to a PSAP prepared both technically and operationally to handle such
   calls, and the vehicle-determined location and crash data made
   available to the call taker simultaneously with the call appearance.
   The PSAP can take advantage of enhanced functionality, including the
   ability to request the vehicle to take an action, such as sending an
   updated set of data, converying a message to the occupants, flashing
   lights, unlocking doors, etc.

   Vehicle manufacturers using the TSP model can choose to take
   advantage of the same mechanism to carry telematics data and requests
   and responses between the vehicle and the TSP for both emergency and
   non-emergency calls as are used for the interface with the PSAP.

   A next-generation IVS establishes a next-generation emergency call
   (see [RFC6443] and [RFC6881]), with an initial INVITE containing a
   Request-URI indicating an ACN type of emergency call and Call-Info
   header fields indicating that both vehicle crash and capabilities
   data are included; the IVS typically does not perform routing or
   location queries but relies on the carrier for this.

   [I-D.ietf-ecrit-ecall] registers new service URN children within the
   "sos" subservice.  These URNs request NG-ACN resources, and
   differentiate between manually and automatically triggered NG-ACN
   calls (which might be subject to different treatment depending on
   policy).  The two service URNs registered in [I-D.ietf-ecrit-ecall]
   are "urn:service:sos.ecall.automatic" and
   "urn:service:sos.ecall.manual".  The same service URNs are used for
   ACN as for eCall since in any region only one of these is supported,
   making a distinction unnecessary.  (Further, PSAP equipment might
   support multiple data formats, allowing a PSAP to handle a vehicle
   that erroneously sent the wrong data object.)



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   Note that in North America, routing queries performed by clients
   outside of an ESInet typically treat all sub-services of "sos"
   identically to "sos" with no sub-service.  However, the Request-URI
   header field retains the full sub-service; route and handling
   decisions within an ESInet or PSAP can take the sub-service into
   account.  For example, in a region with multiple cooperating PSAPs,
   an NG-ACN call might be routed to a PSAP that is NG-ACN capable, or
   one that specializes in vehicle-related incidents.

   Migration of the three architectural models to next-generation (all-
   IP) is described below.

   In the TSP model, the IVS transmits crash and location data to the
   TSP either by re-using the mechanisms and data objects described in
   this document, or using a proprietary mechanism.  In an emergency,
   the TSP bridges in the PSAP and the TSP transmits crash and other
   data to the PSAP using the mechanisms and data objects described in
   this document.  There is a three-way call between the vehicle, the
   TSP, and the PSAP, allowing communication between the PSAP call
   taker, the TSP call taker, and the vehicle occupants (who might be
   unconscious).  The TSP relays PSAP requests and vehicle responses.

                  proprietary
      ///----\\\  or standard       +------+     standard       +------+
     ||| IVS ||| ------------------->+ TSP +------------------->+ PSAP |
      \\\----/// crash + other data +------+ crash + other data +------+

                    Figure 4: Next-Generation TSP Model

   The vehicle manufacturer and the TSP can choose to use the same
   mechanisms and data objects on the left call leg in Figure 4 as on
   the right.  (Note that the TSP model can be more difficult when the
   vehicle is in a different country than the TSP (e.g., a US resident
   driving in Canada) because of the additional complexity in choosing
   the correct PSAP based on vehicle location performed by a TSP in a
   different country.)

   In the direct model, the IVS communicates crash data to the PSAP
   directly using the mechanisms and data objects described in this
   document.

     ///----\\\           NG emergency call              +------+
    ||| IVS |||----------------------------------------->+ PSAP |
     \\\----///          crash + other data              +------+

                  Figure 5: Next-Generation Direct Model





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   In the paired model, the IVS uses a Bluetooth link to a previously-
   paired handset to establish an emergency call with the PSAP; it is
   unclear what facilities are or will be available for transmitting
   crash data through the Bluetooth link to the handset for inclusion in
   an NG emergency call.  Hence, manufacturers that use the paired model
   for legacy calls might choose to adopt either the direct or TSP
   models for next-generation calls.

                                   +---+
      ///----\\\    (undefined)    | H |     standard       +------+
     ||| IVS |||------------------>| S +------------------->+ PSAP |
      \\\----///    (undefined)    +---+ crash + other data +------+

                  Figure 6: Next-Generation Paired Model

   If the call is routed to a PSAP that is not capable of processing the
   vehicle data, the PSAP ignores (or does not receive) the vehicle
   data.  This is detectable by the IVS or TSP when the status response
   to the INVITE (e.g., 200 OK) lacks a metadata/control structure
   acknowledging receipt of the data [I-D.ietf-ecrit-ecall].  The IVS or
   TSP then proceeds as it would for a CS-ACN call (e.g., verbal
   conveyance of data)

6.  Vehicle Data

   The Association of Public-Safety Communications Officials (APCO) and
   the National Emergency Number Association (NENA) have jointly
   developed a standardized set of incident-related vehicle data for ACN
   use, called the Vehicle Emergency Data Set (VEDS) [VEDS].  Such data
   is often referred to as crash data although it is applicable in
   incidents other than crashes.

   VEDS provides a standard data set for the transmission, exchange, and
   interpretation of vehicle-related data.  A standard data format
   allows the data to be generated by an IVS or TSP and interpreted by
   PSAPs, emergency responders, and medical facilities.  It includes
   incident-related information such as airbag deployment, location and
   compass orientation of the vehicle, spatial orientation of the
   vehicle (e.g., upright, on its side or roof or a bumper), various
   sensor data that can indicate the potential severity of the crash and
   the likelihood of severe injuries to the vehicle occupants, etc.
   This data better informs the PSAP and emergency responders as to the
   type of response that might be needed.  Some of this information has
   been included in U.S. government guidelines for field triage of
   injured patients [triage-2008] [triage-2011].  These guidelines are
   designed to help responders identify the potential existence of
   severe internal injuries and to make critical decisions about how and
   where a patient needs to be transported.



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   VEDS is an XML structure (see [VEDS]) transported in SIP using the
   'application/EmergencyCallData.VEDS+xml' MIME media type.

   If new data blocks are needed (e.g., in other regions or for enhanced
   data), the steps required during standardization are briefly
   summarized below:

   o  A set of data is standardized by an SDO or appropriate
      organization
   o  A MIME media type for the crash data set is registered with IANA

      *  If the data is specifically for use in emergency calling, the
         MIME media type is normally under the 'application' type with a
         subtype starting with 'EmergencyCallData.'
      *  If the data format is XML, then by convention the name has a
         suffix of '+xml'
   o  The item is registered in the Emergency Call Data Types registry,
      as defined in Section 11.1.9 of [RFC7852]

      *  For emergency-call-specific formats, the registered name is the
         root of the MIME media type (not including the
         'EmergencyCallData' prefix and any suffix such as '+xml') as
         described in Section 4.1 of [RFC7852].
   o  A new SIP INFO package is registered that permits carrying the new
      media type, the metadata/control object (defined in
      [I-D.ietf-ecrit-ecall]), and for compatibility, the MSD and VEDS
      objects, in SIP INFO requests.

7.  Data Transport

   [RFC7852] establishes a general mechanism for including blocks of
   data within a SIP emergency call.  This document makes use of that
   mechanism.  This document also registers a SIP INFO package (in
   Section 14.7) to enable NG-ACN related data blocks to be carried in
   SIP INFO requests (per [RFC6086], new SIP INFO method usages require
   the definition of a SIP INFO package).

   The Vehicle Emergency Data Set (VEDS) is an XML structure defined by
   the Association of Public-Safety Communications Officials (APCO) and
   the National Emergency Number Association (NENA) [VEDS].  It is
   carried in a body part with MIME media type 'application/
   EmergencyCallData.VEDS+xml'.

   An In-Vehicle System (IVS) transmits a VEDS data block (see [VEDS])
   by including it as a body part of a SIP message per [RFC7852].  The
   body part is identified by its MIME media type ('application/
   emergencyCallData.VEDS+xml') in the Content-Type header field of the
   body part.  The body part is assigned a unique identifier which is



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   listed in a Content-ID header field in the body part.  The SIP
   message is marked as containing the VEDS data by adding (or appending
   to) a Call-Info header field at the top level of the SIP message.
   This Call-Info header field contains a CID URL referencing the body
   part's unique identifier, and a 'purpose' parameter identifying the
   data as a VEDS data block per the Emergency Call Additional Data
   Types registry entry; the 'purpose' parameter's value is
   'emergencyCallData.VEDS'.  A VEDS data block is carried in a SIP INFO
   request by using the SIP INFO package defined in Section 14.7.

   A PSAP or IVS transmits a metadata/control object (see
   [I-D.ietf-ecrit-ecall]) by including it in a SIP message as a MIME
   body part per [RFC7852].  The body part is identified by its MIME
   media type ('application/emergencyCallData.control+xml') in the
   Content-Type header field of the body part.  The body part is
   assigned a unique identifier which is listed in a Content-ID header
   field in the body part.  The SIP message is marked as containing the
   metadata/control block by adding (or appending to) a Call-Info header
   field at the top level of the SIP message.  This Call-Info header
   field contains a CID URL referencing the body part's unique
   identifier, and a 'purpose' parameter identifying the data as a
   metadata/control block per the Emergency Call Additional Data Types
   registry entry; the 'purpose' parameter's value is
   'emergencyCallData.control'.  A metadata/control object is carried in
   a SIP INFO request by using the SIP INFO package defined in
   Section 14.7.

   A body part containing a VEDS or metadata/control object has a
   Content-Disposition header field value containing "By-Reference" and
   is always enclosed in a multipart body part (even if it would
   otherwise be the only body part in the SIP message), since as of the
   date of this document, the use of Content-ID as a SIP header field is
   not defined (while it is defined for use as a MIME header field).

   An In-Vehicle System (IVS) initiating an NG-ACN call includes in the
   initial INVITE a VEDS data block and a metadata/control object
   informing the PSAP of its capabilities.  The VEDS and metadata/
   control body parts (and PIDF-LO) have a Content-Disposition header
   field with the value "By-Reference; handling=optional".  Specifying
   handling=optional prevents the INVITE from being rejected if it is
   processed by a legacy element (e.g., a gateway between SIP and
   circuit-switched environments) that does not understand the VEDS or
   metadata/control (or PIDF-LO) objects.  The PSAP creates a metadata/
   control object acknowledging receipt of the VEDS data and includes it
   in the SIP final response to the INVITE.  The metadata/control object
   is not included in provisional (e.g., 180) responses.





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   If the IVS receives an acknowledgment for a VEDS data object with
   received=false, this indicates that the PSAP was unable to properly
   decode or process the VEDS.  The IVS action is not defined (e.g., it
   might only log an error).  Since the PSAP is able to request an
   updated VEDS during the call, if an initial VEDS is unsatisfactory in
   any way, the PSAP can choose to request another one.

   A PSAP can request that the vehicle send an updated VEDS data block
   during a call.  To do so, the PSAP creates a metadata/control object
   requesting VEDS data and includes it as a body part of a SIP INFO
   request sent within the dialog.  The IVS then includes an updated
   VEDS data object as a body part of a SIP INFO request and sends it
   within the dialog.  If the IVS is unable to send the VEDS, it instead
   sends a metadata/control object acknowledging the request with the
   'success' parameter set to 'false' and a 'reason' parameter (and
   optionally a 'details' parameter) indicating why the request cannot
   be accomplished.  Per [RFC6086], metadata/control objects and VEDS
   data are sent using the SIP INFO package defined in Section 14.7.  In
   addition, to align with the way a VEDS or metadata/control block is
   transmitted in a SIP message other than a SIP INFO request, one or
   more Call-Info header fields are included in the SIP INFO request
   referencing the VEDS or metadata/control block.  See Section 14.7 for
   more information on the use of SIP INFO requests within NG-ACN calls.

   Any metadata/control object sent by a PSAP can request that the
   vehicle perform an action (such as sending a data block, flashing
   lights, providing a camera feed, etc.)  The vehicle sends an
   acknowledgement for any request other than a successfully executed
   send-data action.  Multiple requests with the same 'action' value
   MUST be sent in separate body parts (to avoid any ambiguity in the
   acknowledgement).

   If the IVS is aware that VEDS data it sent previously has changed, it
   MAY send an unsolicited VEDS in any convenient SIP message, including
   a SIP INFO request during the call.  The PSAP sends an acknowledgment
   for an unsolicited VEDS object (if the IVS sent the unsolicited VEDS
   in a SIP INFO request, the acknowledgment is sent in a new SP INFO
   request, otherwise it is sent in the reply to the SIP request
   containing the VEDS).

8.  Call Setup

   A next-generation In-Vehicle System (IVS) initiating an NG-ACN call
   sends a SIP INVITE request using one of the SOS sub-services
   "SOS.ecall.automatic" or "SOS.ecall.manual" in the Request-URI.  This
   SIP INVITE request includes standard sets of both crash and
   capabilities data as described in Section 7.




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   Entities along the path between the vehicle and the PSAP are able to
   identify the call as an ACN call and handle it appropriately.  The
   PSAP is able to identify the crash and capabilities data included in
   the SIP INVITE request by examining the Call-Info header fields for
   'purpose' parameters whose values start with 'EmergencyCallData.'
   The PSAP is able to access the data it is capable of handling and is
   interested in by checking the 'purpose' parameter values.

   This document extends [I-D.ietf-ecrit-ecall] by reusing the call set-
   up and other normative requirements with the exception that in this
   document, support for the eCall MSD is OPTIONAL and support for VEDS
   in REQUIRED.  This document also adds new attribute values to the
   metadata/control object defined in [I-D.ietf-ecrit-ecall].

9.  New Metadata/Control Values

   This document adds new attribute values to the metadata/control
   structure defined in [I-D.ietf-ecrit-ecall].

      In addition to the base usage from the PSAP to the IVS to
      acknowledge receipt of crash data, the <ack> element is also
      contained in a metadata/control block sent by the IVS to the PSAP.
      This is used by the IVS to acknowledge receipt of a request by the
      PSAP and indicate if the request was carried out when that request
      would not otherwise be acknowledged (if the PSAP requests the
      vehicle to send data and the vehicle does so, the data serves as a
      success acknowledgement).
      The <capabilities> element is used in a metadata/control block
      sent from the IVS to the PSAP (e.g., in the initial INVITE) to
      inform the PSAP of the vehicle capabilities.  Child elements
      contain all actions and data types supported by the vehicle and
      all available lamps (lights) and cameras.
      New request values are added to the <request> element to enable
      the PSAP to request the vehicle to perform actions.

   Mandatory Actions (the IVS and the PSAP MUST support):

   o  Transmit data object (VEDS MUST be supported; MSD MAY be
      supported)

   Optional Actions (the IVS and the PSAP MAY support):

   o  Play and/or display static (pre-defined) message
   o  Speak/display dynamic text (text supplied in action)
   o  Flash or turn on or off a lamp (light)
   o  Honk horn
   o  Lock or unlock doors
   o  Enable a camera



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   The <ack> element indicates the object being acknowledged (i.e., a
   data object or a metadata/control block containing <request>
   elements), and reports success or failure.

   The <capabilities> element has child <request> elements indicating
   the actions supported by the IVS.

   The <request> element contains attributes to indicate the request and
   to supply any needed information, and MAY contain a <text> child
   element to contain the text for a dynamic message.  The 'action'
   attribute is mandatory and indicates the specific action.
   [I-D.ietf-ecrit-ecall] established an IANA registry to contain the
   allowed values; this document adds new values to that registry in
   Table 2.

   Per [I-D.ietf-ecrit-ecall], the PSAP sends a metadata/control block
   in response to the VEDS data sent by the IVS in SIP requests other
   than INFO (e.g., the INVITE).  This metadata/control block is sent in
   the SIP response to the request (e.g., the INVITE response).  When
   the PSAP needs to send a control block that is not an immediate
   response to a VEDS or other data sent by the IVS, the metadata/
   control block is transmitted from the PSAP to the IVS in a SIP INFO
   request within the established dialog.  The IVS sends the requested
   data (e.g., the VEDS) or an acknowledgment (for requests other than
   to send data or to indicate an inability to send the requested data)
   in a new SIP INFO request.  This mechanism flexibly allows the PSAP
   to send metadata/control data to the IVS and the IVS to respond.  If
   a metadata/control block sent in a SIP response message requests the
   IVS to send a new VEDS or other data block, or to perform an action
   other than sending data, the IVS sends the requested data or an
   acknowledgment regarding the action in a SIP INFO request within the
   dialog.

9.1.  New values for the 'action' attribute'

   The following new "action" values are defined:

   msg-static  displays or plays a predefined message (translated as
      appropriate for the language of the vehicle's interface).  A
      registry is created in Section 14.4 for messages and their IDs.
      Vehicles include the highest registered message in their
      <capabilities> element to indicate support for all messages up to
      and including the indicated value.  A registry of message
      identification values is defined in Section 14.4.  There is only
      one static message initially defined (listed in Table 3).  Because
      all compliant vehicles are expected to support all static messages
      translated into all languages supported by the vehicle, it is
      important to limit the number of such messages.  Therefore, this



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      registry operates under "Specification Required" rules as defined
      in [RFC5226], which require a stable, public document and implies
      expert review of the publication.

   msg-dynamic  displays or speaks (via text-to-speech) a dynamic
      message contained in a child <text> element within the request.

   honk  sounds the horn.

   lamp  turns a lamp (light) on, off, or flashes.  The lamp is
      identified by a lamp ID token contained in an "element-id"
      attribute of the request.  The desired state of the lamp is either
      "on", "off", or "flash" as indicated in a "requested-state"
      attribute.  The duration of the lamp's requested state is
      specified in a "persistence" attribute.  A registry of lamp
      identification values is defined in Section 14.5.  The initial
      values (listed in Table 4) are head, interior, fog-front, fog-
      rear, brake, brake-center, position-front, position-rear, turn-
      left, turn-right, and hazard.

   enable-camera  adds a one-way media stream (established via SIP re-
      INVITE sent by the vehicle) to enable the PSAP call taker to view
      a feed from a camera.  A registry of camera identification values
      is defined in Section 14.6.  The initial values (listed in
      Table 5) are backup, left-rear, right-rear, forward, rear-wide,
      lane, interior, night-front, night-rear, night-left, and night-
      right.

   door-lock  locks or unlocks all door locks.  A "requested-state"
      attribute contains either "locked" or "unlocked" to indicate if
      the doors are to be locked or unlocked.

   Note that there is no 'request' action to play dynamic media (such as
   an audio message).  The PSAP can send a SIP re-INVITE to establish a
   one-way media stream for this purpose.

9.2.  Request Example














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       <?xml version="1.0" encoding="UTF-8"?>
       <EmergencyCallData.control
           xmlns="urn:ietf:params:xml:ns:EmergencyCallData:control"
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">

       <request action="send-data" datatype="VEDS"/>
       <request action="lamp" element-id="hazard"
                requested-state="flash" persistence="PT1H"/>
       <request action="msg-static" int-id="1"/>
       <request action="msg-dynamic">
           <text>Remain calm.  Help is on the way.</text>
       </request>

       </EmergencyCallData.control>


                         Figure 7: Request Example

9.3.  The <ack> element

   In [I-D.ietf-ecrit-ecall], the <ack> element is transmitted by the
   PSAP to acknowledge the MSD.  Here, the <ack> element is also
   transmitted by the PSAP to acknowledge the VEDS data and by the IVS
   to acknowledge receipt of a <request> element that requested the IVS
   to perform an action other than transmitting a data object (e.g., a
   request to display a message would be acknowledged, but a request to
   transmit VEDS data would not result in a separate <ack> element being
   sent, since the data object itself serves as acknowledgment.)  An
   <ack> element sent by an IVS references the unique ID of the
   metadata/control object containing the request(s) and indicates
   whether the request was successfully performed, and if not,
   optionally includes an explanation.

9.3.1.  Ack Examples

















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       <?xml version="1.0" encoding="UTF-8"?>
       <EmergencyCallData.control
           xmlns="urn:ietf:params:xml:ns:EmergencyCallData:control"
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">

       <ack ref="1234567890@atlanta.example.com">
           <actionResult action="msg-dynamic" success="true"/>
           <actionResult action="lamp" success="false" reason="unable"
                         details="The requested lamp is inoperable"/>
       </ack>

       </EmergencyCallData.control>


                  Figure 8: Ack Example from IVS to PSAP

9.4.  The <capabilities> element

   The <capabilities> element ([I-D.ietf-ecrit-ecall]) is transmitted by
   the IVS to indicate its capabilities to the PSAP.

   The <capabilities> element contains a <request> child element per
   action supported by the vehicle.  The vehicle MUST support sending
   the VEDS data object and so includes at a minimum a <request> child
   element with the 'action' attribute set to "send-data" and the
   'supported-values' attribute containing all data blocks supported by
   the IVS, which MUST include 'VEDS'.  All other actions are OPTIONAL.

   If the "msg-static" action is supported, a <request> child element
   with the 'action' attribute set to "msg-static" is included, with the
   'int-id' attribute set to the highest supported static message
   supported by the vehicle.  A registry is created in Section 14.4 to
   map 'int-id' values to static text messages.  By sending the highest
   supported static message number in its <capabilities> element, the
   vehicle indicates its support for all static messages in the registry
   up to and including that value.

   If the "lamp" action is supported, a <request> child element with the
   'action' attribute set to "lamp" is included, with the 'supported-
   values' attribute set to all supported lamp IDs.  A registry is
   created in Section 14.5 to contain lamp ID values.

   If the "enable-camera" action is supported, a <request> child element
   with the 'action' attribute set to "enable-camera" is included, with
   the 'supported-values' attribute set to all supported camera IDs.  A
   registry is created in Section 14.6 to contain camera ID values.





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9.4.1.  Capabilities Example


       <?xml version="1.0" encoding="UTF-8"?>
       <EmergencyCallData.control
           xmlns="urn:ietf:params:xml:ns:EmergencyCallData:control"
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">

       <capabilities>
           <request action="send-data" supported-values="VEDS"/>
           <request action="lamp"
                    supported-values="head;interior;fog-front;
                    fog-rear;brake;position-front;position-rear;
                    turn-left;turn-right;hazard"/>
           <request action="msg-static" int-id="3"/>
           <request action="msg-dynamic"/>
           <request action="honk"/>
           <request action="enable-camera"
                    supported-values="backup; interior"/>
           <request action="door-lock"/>
       </capabilities>

       </EmergencyCallData.control>


                      Figure 9: Capabilities Example

10.  Test Calls

   An NG-ACN test call is a call that is recognized and treated to some
   extent as an NG-ACN call but not given emergency call treatment and
   not handled by a call taker.  The specific handling of test NG-ACN
   calls is not itself standardized; the test call facility is intended
   to allow the IVS, user, or TSP to verify that an NG-ACN call can be
   successfully established with voice and/or other media communication.
   The IVS might also be able to verify that the crash data was
   successfully received.

   This document builds on [I-D.ietf-ecrit-ecall], which inherits the
   ability to utilize test call functionality from Section 15 of
   [RFC6881].  A service URN starting with "test." indicates a test
   call.  [I-D.ietf-ecrit-ecall] registered "urn:service:test.sos.ecall"
   for test calls.

   MNOs, emergency authorities, ESInets, and PSAPs determine how to
   treat a vehicle call requesting the "test" service URN so that the
   desired functionality is tested, but this is outside the scope of
   this document.  (One possibility is that MNOs route such calls as



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   non-emergency calls to an ESInet, which routes them to a PSAP that
   supports NG-ACN calls; the PSAP accepts test calls, sends a crash
   data acknowledgment, and plays an audio clip (for example, saying
   that the call reached an appropriate PSAP and the vehicle data was
   successfully processed) in addition to supporting media loopback per
   [RFC6881]).

   Note that since test calls are placed using "test" as the parent
   service URN and "sos" as a child, such calls are not treated as an
   emergency call and so some functionality might not apply (such as
   preemption or service availability for devices lacking service ("non-
   service-initialized" or "NSI" devices) if those are available for
   emergency calls).

11.  Example

   Figure 10 shows an NG-ACN call routing.  The mobile network operator
   (MNO) routes the call to an Emergency services IP Network (ESInet),
   as for any emergency call.  The ESInet routes the call to an
   appropriate NG-ACN-capable PSAP (using location information and the
   fact that that it is an NG-ACN call).  The call is processed by the
   Emergency Services Routing Proxy (ESRP), as the entry point to the
   ESInet.  The ESRP routes the call to an appropriate NG-ACN-capable
   PSAP, where the call is received by a call taker.  (In deployments
   where there is no ESInet, the MNO itself routes the call directly to
   an appropriate NG-ACN-capable PSAP.)

                               +---------------------------------------+
                               |                                       |
               +------------+  |                  +-------+            |
               |            |  |                  | PSAP2 |            |
               |            |  |                  +-------+            |
               | Originating|  |                                       |
               |   Mobile   |  |  +------+     +-------+               |
     Vehicle-->|  Network   |--+->| ESRP |---->| PSAP1 |--> Call-Taker |
               |            |  |  +------+     +-------+               |
               |            |  |                                       |
               +------------+  |                  +-------+            |
                               |                  | PSAP3 |            |
                               |                  +-------+            |
                               |                                       |
                               |                                       |
                               |                                       |
                               |                ESInet                 |
                               +---------------------------------------+

     Figure 10: Example of Vehicle-Placed Emergency Call Message Flow




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   The example, shown in Figure 11, illustrates a SIP emergency call
   INVITE request with location information (a PIDF-LO), VEDS crash data
   (a VEDS data block), and capabilities data (a metadata/control block
   with extensions defined in this document) included in the SIP INVITE
   request message.  The INVITE has a request URI containing the
   'urn:service:sos.ecall.automatic' service URN.

   The example VEDS data structure shows information about a crashed
   vehicle.  The example communicates that the car is a model year 2015
   Saab 9-5 (a car which does not exist).  The front airbag deployed as
   a consequence of the crash.  The 'VehicleBodyCategoryCode' indicates
   that the crashed vehicle is a passenger car (the code is set to
   '101') and that it is not a convertible (the 'ConvertibleIndicator'
   value is set to 'false').

   The 'VehicleCrashPulse' element provides further information about
   the crash, namely that the force of impact based on the change in
   velocity over the duration of the crash pulse was 100 MPH.  The
   principal direction of the force of the impact is set to '12' (which
   refers to 12 O'Clock, corresponding to a frontal collision).  This
   value is described in the 'CrashPulsePrincipalDirectionOfForceValue'
   element.

   The 'CrashPulseRolloverQuarterTurnsValue' indicates the number of
   quarter turns in concert with a rollover expressed as a number; in
   our case 1.

   No roll bar was deployed, as indicated in
   'VehicleRollbarDeployedIndicator' being set to 'false'.

   Next, there is information indicating seatbelt and seat sensor data
   for individual seat positions in the vehicle.  In our example,
   information from the driver seat is available (value '1' in the
   'VehicleSeatLocationCategoryCode' element), that the seatbelt was
   monitored ('VehicleSeatbeltMonitoredIndicator' element), that the
   seatbelt was fastened ('VehicleSeatbeltFastenedIndicator' element)
   and the seat sensor determined that the seat was occupied
   ('VehicleSeatOccupiedIndicator' element).

   Finally, information about the weight of the vehicle, which is 600
   kilogram in our example.

   In addition to the information about the vehicle, further indications
   are provided, namely the presence of fuel leakage
   ('FuelLeakingIndicator' element), an indication whether the vehicle
   was subjected to multiple impacts ('MultipleImpactsIndicator'
   element), the orientation of the vehicle at final rest
   ('VehicleFinalRestOrientationCategoryCode' element) and an indication



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   that there are no parts of the vehicle on fire (the
   'VehicleFireIndicator' element).

     INVITE urn:service:sos.ecall.automatic SIP/2.0
     To: urn:service:sos.ecall.automatic
     From: <sip:+13145551111@example.com>;tag=9fxced76sl
     Call-ID: 3848276298220188511@atlanta.example.com
     Geolocation: <cid:target123@example.com>
     Geolocation-Routing: no
     Call-Info: <cid:1234567890@atlanta.example.com>;
                purpose=EmergencyCallData.VEDS
     Call-Info: <cid:1234567892@atlanta.example.com>;
                purpose=emergencyCallData.control
     Accept: application/sdp, application/pidf+xml,
             application/emergencyCallData.control+xml
     Recv-Info: emergencyCallData.eCall
     Allow: INVITE, ACK, PRACK, INFO, OPTIONS, CANCEL, REFER, BYE,
            SUBSCRIBE, NOTIFY, UPDATE
     CSeq: 31862 INVITE
     Content-Type: multipart/mixed; boundary=boundary1
     Content-Length: ...

     --boundary1
     Content-Type: application/sdp

     ...Session Description Protocol (SDP) goes here

     --boundary1
      Content-Type: application/pidf+xml
      Content-ID: <target123@atlanta.example.com>
      Content-Disposition: by-reference;handling=optional

      <?xml version="1.0" encoding="UTF-8"?>
      <presence
         xmlns="urn:ietf:params:xml:ns:pidf"
         xmlns:dm="urn:ietf:params:xml:ns:pidf:data-model"
         xmlns:gp="urn:ietf:params:xml:ns:pidf:geopriv10"
         xmlns:dyn="urn:ietf:params:xml:ns:pidf:geopriv10:dynamic"
         xmlns:gml="http://www.opengis.net/gml"
         xmlns:gs="http://www.opengis.net/pidflo/1.0"
         entity="sip:+13145551111@example.com">
         <dm:device id="123">
             <gp:geopriv>
                 <gp:location-info>
                     <gml:Point srsName="urn:ogc:def:crs:EPSG::4326">
                        <gml:pos>-34.407 150.883</gml:pos>
                     </gml:Point>
                      <dyn:Dynamic>



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                         <dyn:heading>278</dyn:heading>
                         <dyn:direction><dyn:direction>
                      </dyn:Dynamic>
                 </gp:location-info>
                 <gp:usage-rules/>
                 <method>gps</method>
             </gp:geopriv>
             <timestamp>2012-04-5T10:18:29Z</timestamp>
             <dm:deviceID>1M8GDM9A_KP042788</dm:deviceID>
         </dm:device>
  </presence>

      --boundary1
      Content-Type: application/EmergencyCallData.VEDS+xml
      Content-ID: <1234567890@atlanta.example.com>
      Content-Disposition: by-reference;handling=optional

      <?xml version="1.0" encoding="UTF-8"?>
      <AutomatedCrashNotification xmlns="http://www.veds.org/acn/1.0"
          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

      <Crash>
          <CrashVehicle>
              <ItemMakeName xmlns="http://niem.gov/niem/niem-core/2.0">
                  Saab
              </ItemMakeName>
              <ItemModelName xmlns="http://niem.gov/niem/niem-core/2.0">
                  9-5
              </ItemModelName>
              <ItemModelYearDate
                  xmlns="http://niem.gov/niem/niem-core/2.0">
                  2015
              </ItemModelYearDate>
              <Airbag>
                  <AirbagCategoryCode>FRONT</AirbagCategoryCode>
                  <AirbagDeployedIndicator>true
                  </AirbagDeployedIndicator>
              </Airbag>
              <ConvertibleIndicator>false</ConvertibleIndicator>
              <PowerSourceCategoryCode>MAIN</PowerSourceCategoryCode>
              <VehicleBodyCategoryCode
                  xmlns="http://niem.gov/niem/domains/jxdm/4.1">
                  101
              </VehicleBodyCategoryCode>
              <VehicleCrashPulse>
                  <CrashPulseChangeInVelocityMeasure>
                      <MeasurePointValue
                          xmlns="http://niem.gov/niem/niem-core/2.0">



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                          100
                      </MeasurePointValue>
                      <MeasureUnitText
                          xmlns="http://niem.gov/niem/niem-core/2.0">
                          MPH</MeasureUnitText>
                   </CrashPulseChangeInVelocityMeasure>
                          <CrashPulsePrincipalDirectionOfForceValue>12
                          </CrashPulsePrincipalDirectionOfForceValue>
                  <CrashPulseRolloverQuarterTurnsValue>1
                  </CrashPulseRolloverQuarterTurnsValue>
              </VehicleCrashPulse>
              <VehicleRollbarDeployedIndicator>false
              </VehicleRollbarDeployedIndicator>
              <VehicleSeat>
                  <VehicleSeatLocationCategoryCode>1
                  </VehicleSeatLocationCategoryCode>
                  <VehicleSeatOccupiedIndicator>true
                  </VehicleSeatOccupiedIndicator>
                  <VehicleSeatbeltFastenedIndicator>true
                  </VehicleSeatbeltFastenedIndicator>
                  <VehicleSeatbeltMonitoredIndicator>true
                  </VehicleSeatbeltMonitoredIndicator>
              </VehicleSeat>
              <VehicleUnladenWeightMeasure
                  xmlns="http://niem.gov/niem/niem-core/2.0">
                  <MeasurePointValue
                      xmlns="http://niem.gov/niem/niem-core/2.0">
                      600
                      </MeasurePointValue>
                  <MeasureUnitText
                      xmlns="http://niem.gov/niem/niem-core/2.0">
                      kilogram
                  </MeasureUnitText>
              </VehicleUnladenWeightMeasure>
          </CrashVehicle>
          <FuelLeakingIndicator>true</FuelLeakingIndicator>
          <MultipleImpactsIndicator>false</MultipleImpactsIndicator>
          <SevereInjuryIndicator>true</SevereInjuryIndicator>
          <VehicleFinalRestOrientationCategoryCode>Driver
          </VehicleFinalRestOrientationCategoryCode>
          <VehicleFireIndicator>false</VehicleFireIndicator>
      </Crash>
  </AutomatedCrashNotification>

      --boundary1
      Content-Type: application/emergencyCallData.control+xml
      Content-ID: <1234567892@atlanta.example.com>
      Content-Disposition: by-reference;handling=optional



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      <?xml version="1.0" encoding="UTF-8"?>
      <EmergencyCallData.control
           xmlns="urn:ietf:params:xml:ns:EmergencyCallData:control"
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">

       <capabilities>
           <request action="send-data" supported-datatypes="VEDS"/>
           <request action="lamp"
                    supported-values="head;interior;fog-front;fog-rear;
                    brake;position-front;position-rear;turn-left;
                    turn-right;hazard"/>
           <request action="msg-static" int-id="3"/>
           <request action="msg-dynamic"/>
           <request action="honk"/>
           <request action="enable-camera"
                    supported-values="backup;interior"/>
           <request action="door-lock"/>
       </capabilities>

      </EmergencyCallData.control>

      --boundary1--

        Figure 11: SIP INVITE for a Vehicle-Initated Emergency Call

12.  Security Considerations

   Since this document relies on [I-D.ietf-ecrit-ecall] and [RFC7852],
   the security considerations described there and in [RFC5069] apply
   here.  Implementors are cautioned to read and understand the
   discussion in those documents.

   As with emergency service systems where location data is supplied or
   determined with the assistance of an end host, there is the
   possibility that that location is incorrect, either intentially
   (e.g., in a denial of service attack against the emergency services
   infrastructure) or due to a malfunctioning device.  The reader is
   referred to [RFC7378] for a discussion of some of these
   vulnerabilities.

   In addition to the security considerations discussion specific to the
   metadata/control object in [I-D.ietf-ecrit-ecall], note that vehicles
   MAY decline to carry out any requested action (e.g., if the vehicle
   requires but is unable to verify the certificate used to sign the
   request).  The vehicle MAY use any value in the reason registry to
   indicate why it did not take an action (e.g., the generic "unable" or
   the more specific "security-failure").  Because some actions carry
   more potential risk than others (e.g., unlocking a door versus



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   flashing lights), vehicle policy MAY decline to carry out some
   requests in some circumstances (e.g., declining a request to unlock
   doors, send an updated VEDS, or enable a camera received in a
   vehicle-terminated call while carrying out such requests received in
   a vehicle-initiated emergency call).

13.  Privacy Considerations

   Since this document builds on [I-D.ietf-ecrit-ecall], which itself
   builds on [RFC7852], the data structures specified there, and the
   corresponding privacy considerations discussed there, apply here as
   well.  The VEDS data structure contains optional elements that can
   carry identifying and personal information, both about the vehicle
   and about the owner, as well as location information, and so needs to
   be protected against unauthorized disclosure, as discussed in
   [RFC7852].  Local regulations may impose additional privacy
   protection requirements.

   The additional functionality enabled by this document, such as access
   to vehicle camera streams, carries a burden of protection and so
   implementations need to be careful that access is only provided
   within the context of an emergency call or to an emergency services
   provider (e.g., by verifying that the request for camera access is
   signed by a certificate issued by an emergency services registrar).

14.  IANA Considerations

   This document registers the 'application/EmergencyCall.VEDS+xml' MIME
   media type, and adds "VEDS" to the Emergency Call Data Types
   registry.  This document adds to and creates sub-registries in the
   "Emergency Call Metadata/Control Data" registry created in
   [I-D.ietf-ecrit-ecall].  This document registers a new SIP INFO
   package.

14.1.  MIME Media Type Registration for 'application/
       EmergencyCall.VEDS+xml'

   This specification requests the registration of a new MIME media type
   according to the procedures of RFC 6838 [RFC6838] and guidelines in
   RFC 7303 [RFC7303].

      MIME media type name: application

      MIME subtype name: EmergencyCallData.VEDS+xml

      Mandatory parameters: none

      Optional parameters: charset



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      Indicates the character encoding of enclosed XML.

      Encoding considerations: Uses XML, which can employ 8-bit
      characters, depending on the character encoding used.  See
      Section 3.2 of RFC 7303 [RFC7303].

      Security considerations:

         This media type is designed to carry vehicle crash data during
         an emergency call.

         This data can contain personal information including vehicle
         VIN, location, direction, etc.  Appropriate precautions need to
         be taken to limit unauthorized access, inappropriate disclosure
         to third parties, and eavesdropping of this information.
         Please refer to Section 9 and Section 10 of [RFC7852] for more
         information.

         When this media type is contained in a signed or encrypted body
         part, the enclosing multipart (e.g., multipart/signed or
         multipart/encrypted) has the same Content-ID as the data part.
         This allows an entity to identify and access the data blocks it
         is interested in without having to dive deeply into the message
         structure or decrypt parts it is not interested in.  (The
         'purpose' parameter in a Call-Info header field identifies the
         data, and the CID URL points to the data block in the body,
         which has a matching Content-ID body part header field).

      Interoperability considerations: None

      Published specification: [VEDS]

      Applications which use this media type: Emergency Services

      Additional information: None

      Magic Number: None

      File Extension: .xml

      Macintosh file type code: 'TEXT'

      Persons and email addresses for further information: Randall
      Gellens rg+ietf@randy.pensive.org; Hannes Tschofenig,
      Hannes.Tschofenig@gmx.net

      Intended usage: LIMITED USE




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      Author: This specification is a work item of the IETF ECRIT
      working group, with mailing list address <ecrit@ietf.org>.

      Change controller: The IESG <ietf@ietf.org>

14.2.  Registration of the 'VEDS' entry in the Emergency Call Data Types
       registry

   This specification requests IANA to add the 'VEDS' entry to the
   Emergency Call Data Types registry, with a reference to this
   document; the 'Data About' value is 'The Call'.  The Emergency Call
   Data types registry was established by [RFC7852].

14.3.  New Action Values

   This document adds new values for the 'action' attribute of the
   <request> element in the "Emergency Call Action" registry created by
   [I-D.ietf-ecrit-ecall].

          +---------------+-------------------------------------+
          |      Name     |             Description             |
          +---------------+-------------------------------------+
          |   msg-static  | Section 9.1 of [TBD: THIS DOCUMENT] |
          |               |                                     |
          |  msg-dynamic  | Section 9.1 of [TBD: THIS DOCUMENT] |
          |               |                                     |
          |      honk     | Section 9.1 of [TBD: THIS DOCUMENT] |
          |               |                                     |
          |      lamp     | Section 9.1 of [TBD: THIS DOCUMENT] |
          |               |                                     |
          | enable-camera | Section 9.1 of [TBD: THIS DOCUMENT] |
          |               |                                     |
          |   door-lock   | Section 9.1 of [TBD: THIS DOCUMENT] |
          +---------------+-------------------------------------+

            Table 2: Emergency Call Action Registry New Values

14.4.  Emergency Call Static Message Registry

   This document creates a new sub-registry called "Emergency Call
   Static Message" in the "Emergency Call Metadata/Control Data"
   registry established by [I-D.ietf-ecrit-ecall].  Because all
   compliant vehicles are expected to support all static messages
   translated into all languages supported by the vehicle, it is
   important to limit the number of such messages.  As defined in
   [RFC5226], this registry operates under "Specification Required"
   rules, which require a stable, public document and implies expert
   review of the publication.  The expert should determine that the



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   document has been published by an appropriate emergency services
   organization (e.g., NENA, EENA, APCO) or by the IETF with input from
   an emergency services organization, and that the proposed message is
   sufficiently distinguishable from other messages.

   The contents of this registry are:

   ID:  An integer identifier to be used in the 'int-id' attribute of a
      metadata/control <request> element.

   Message:  The text of the message.  Messages are listed in the
      registry in English; vehicles are expected to implement
      translations into languages supported by the vehicle.

   When new messages are added to the registry, the message text is
   determined by the registrant; IANA assigns the IDs.  Each message is
   assigned a consecutive integer value as its ID.  This allows an IVS
   to indicate by a single integer value that it supports all messages
   with that value or lower.

   The initial set of values is listed in Table 3.

   +----+--------------------------------------------------------------+
   | ID | Message                                                      |
   +----+--------------------------------------------------------------+
   | 1  | Emergency services has received your information and         |
   |    | location, but cannot speak with you right now.  We will get  |
   |    | help to you as soon as possible.                             |
   +----+--------------------------------------------------------------+

      Table 3: Emergency Call Static Message Registry Initial Values

14.5.  Emergency Call Vehicle Lamp ID Registry

   This document creates a new sub-registry called "Emergency Call
   Vehicle Lamp ID" in the "Emergency Call Metadata/Control Data"
   registry established by [I-D.ietf-ecrit-ecall].  This new sub-
   registry uniquely identifies the names of automotive lamps (lights).
   As defined in [RFC5226], this registry operates under "Expert Review"
   rules.  The expert should determine that the proposed lamp name is
   clearly understandable and is sufficiently distinguishable from other
   lamp names.

   The contents of this registry are:

   Name:  The identifier to be used in the 'element-id' attribute of a
      metadata/control <request> element.




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   Description:  A description of the lamp (light).

   The initial set of values is listed in Table 4.

     +----------------+---------------------------------------------+
     | Name           | Description                                 |
     +----------------+---------------------------------------------+
     | head           | The main lamps used to light the road ahead |
     |                |                                             |
     | interior       | Interior lamp, often at the top center      |
     |                |                                             |
     | fog-front      | Front fog lamps                             |
     |                |                                             |
     | fog-rear       | Rear fog lamps                              |
     |                |                                             |
     | brake          | Brake indicator lamps                       |
     |                |                                             |
     | brake-center   | Center High Mounted Stop Lamp               |
     |                |                                             |
     | position-front | Front position/parking/standing lamps       |
     |                |                                             |
     | position-rear  | Rear position/parking/standing lamps        |
     |                |                                             |
     | turn-left      | Left turn/directional lamps                 |
     |                |                                             |
     | turn-right     | Right turn/directional lamps                |
     |                |                                             |
     | hazard         | Hazard/four-way lamps                       |
     +----------------+---------------------------------------------+

          Table 4: Emergency Call Lamp ID Registry Initial Values

14.6.  Emergency Call Vehicle Camera ID Registry

   This document creates a new sub-registry called "Emergency Call
   Vehicle Camera ID" in the "Emergency Call Metadata/Control Data"
   registry established by [I-D.ietf-ecrit-ecall].  This new sub-
   registry uniquely identifies automotive cameras.  As defined in
   [RFC5226], this registry operates under "Expert Review" rules.  The
   expert should determine that the proposed camera name is clearly
   understandable and is sufficiently distinguishable from other camera
   names.

   The contents of this registry are:

   Name:  The identifier to be used in the 'element-id' attribute of a
      control <request> element.




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   Description:  A description of the camera.

   The initial set of values is listed in Table 5.

   +-------------+-----------------------------------------------------+
   | Name        | Description                                         |
   +-------------+-----------------------------------------------------+
   | backup      | Shows what is behind the vehicle, e.g., often used  |
   |             | for driver display when the vehicle is in reverse.  |
   |             | Also known as rearview, reverse, rear visibility,   |
   |             | etc.                                                |
   |             |                                                     |
   | left-rear   | Shows view to the left and behind (e.g., left side  |
   |             | rear-view mirror or blind spot view)                |
   |             |                                                     |
   | right-rear  | Shows view to the right and behind (e.g., right     |
   |             | side rear-view mirror or blind spot view)           |
   |             |                                                     |
   | forward     | Shows what is in front of the vehicle               |
   |             |                                                     |
   | rear-wide   | Shows what is behind vehicle (e.g., used by rear-   |
   |             | collision detection systems), separate from backup  |
   |             | view                                                |
   |             |                                                     |
   | lane        | Used by systems to identify road lane and/or        |
   |             | monitor vehicle's position within lane              |
   |             |                                                     |
   | interior    | Shows the interior (e.g., driver)                   |
   |             |                                                     |
   | night-front | Night-vision view of what is in front of the        |
   |             | vehicle                                             |
   |             |                                                     |
   | night-rear  | Night-vision view of what is behind the vehicle     |
   |             |                                                     |
   | night-left  | Night-vision view of what is to the left of the     |
   |             | vehicle                                             |
   |             |                                                     |
   | night-right | Night-vision view of what is to the right of the    |
   |             | vehicle                                             |
   +-------------+-----------------------------------------------------+

     Table 5: Emergency Call Vehicle Camera ID Registry Initial Values

14.7.  The emergencyCallData.eCall.VEDS SIP INFO package

   This document registers the 'emergencyCallData.eCall.VEDS' SIP INFO
   package.




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   Both endpoints (the IVS and the PSAP equipment) include
   'emergencyCallData.eCall.VEDS' in a Recv-Info header field per
   [RFC6086] to indicate ability to receive SIP INFO messages carrying
   data as described here.

   Support for the 'emergencyCallData.eCall.VEDS' SIP INFO package
   indicates the ability to receive NG-ACN related body parts as
   specified in [TBD: THIS DOCUMENT].

   A SIP INFO request message carrying data related to an emergency call
   as described in [TBD: THIS DOCUMENT] has an Info-Package header field
   set to 'emergencyCallData.eCall.VEDS' per [RFC6086].

   The requirements of Section 10 of [RFC6086] are addressed in the
   following sections.

14.7.1.  Overall Description

   This section describes "what type of information is carried in Info
   requests associated with the Info Package, and for what types of
   applications and functionalities UAs can use the Info Package."

   SIP INFO requests associated with the emergencyCallData.eCall.VEDS
   SIP INFO package carry data associated with emergency calls as
   defined in [TBD: THIS DOCUMENT].  The application is vehicle-
   initiated emergency calls established using SIP.  The functionality
   is to carry vehicle data and metadata/control information between
   vehicles and PSAPs.  Refer to [TBD: THIS DOCUMENT] for more
   information.

14.7.2.  Applicability

   This section describes "why the Info Package mechanism, rather than
   some other mechanism, has been chosen for the specific use-case...."

   The use of the SIP INFO method is based on an analysis of the
   requirements against the intent and effects of the INFO method versus
   other approaches (which included the SIP MESSAGE method, SIP OPTIONS
   method, SIP re-INVITE method, media plane transport, and non-SIP
   protocols).  In particular, the transport of emergency call data
   blocks occurs within a SIP emergency dialog, per Section 7, and is
   normally carried in the initial INVITE request and its response; the
   use of the INFO method only occurs when emergency-call-related data
   needs to be sent mid-call.  While the SIP MESSAGE method could be
   used, it is not tied to a SIP dialog as is the INFO method and thus
   might not be associated with the dialog.  Both the SIP OPTIONS or re-
   INVITE methods could also be used, but is seen as less clean than the
   INFO method.  The SIP SUBSCRIBE/NOTIFY method could be coerced into



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   service, but the semantics are not a good fit, e.g., the subscribe/
   notify mechanism provides one-way communication consisting of (often
   multiple) notifications from notifier to subscriber indicating that
   certain events in notifier have occurred, whereas what's needed here
   is two-way communication of data related to the emergency dialog.
   Use of the media plane mechanisms was discounted because the number
   of messages needing to be exchanged in a dialog is normally zero or
   very few, and the size of the data is likewise very small.  The
   overhead caused by user plane setup (e.g., to use MSRP as transport)
   would be disproportionately large.

   Based on the analyses, the SIP INFO method was chosen to provide for
   mid-call data transport.

14.7.3.  Info Package Name

   The SIP INFO package name is emergencyCallData.eCall.VEDS

14.7.4.  Info Package Parameters

   None

14.7.5.  SIP Option-Tags

   None

14.7.6.  INFO Request Body Parts

   The body of an emergencyCallData.eCall.VEDS SIP INFO package is a
   multipart body which MAY contain zero or one application/
   emergencyCallData.eCall.VEDS+xml (containing a VEDS data block) part,
   zero or more application/emergencyCallData.control+xml (containing a
   metadata/control object) parts, and zero or one application/
   emergencyCallData.eCall.MSD+per (containing an MSD) part.  At least
   one VEDS, MSD, or metadata/control body part is expected; the
   behavior upon receiving a SIP INFO request with none is undefined.

   The body parts are sent per [RFC6086], and in addition, to align with
   with how these body parts are sent in non-INFO messages, each
   associated body part is referenced by a Call-Info header field at the
   top level of the SIP message.  The body part has a Content-
   Disposition header field set to "By-Reference".

   A VEDS or metadata/control block is always enclosed in a multipart
   body part (even if it would otherwise be the only body part in the
   SIP message), since as of the date of this document, the use of
   Content-ID as a SIP header field is not defined (while it is defined
   for use as a MIME header field).  The innermost multipart that



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   contains only body parts associated with the SIP INFO package has a
   Content-Disposition value of Info-Package.

   Service providers are not expected to add [RFC7852] Additional Data
   to SIP INFO requests.

   See [TBD: THIS DOCUMENT] for more information.

14.7.7.  Info Package Usage Restrictions

   Usage is limited to vehicle-initiated emergency calls as defined in
   [TBD: THIS DOCUMENT].

14.7.8.  Rate of INFO Requests

   The SIP INFO request is used within an established emergency call
   dialog for the PSAP to request the IVS to send an updated data set,
   and for the IVS to send the requested data set.  Because this is
   normally done only on manual request of the PSAP call taker (who
   suspects some aspect of the vehicle state has changed), the rate of
   SIP INFO requests associated with the emergencyCallData.eCall.VEDS
   SIP INFO package is normally quite low (most dialogs are likely to
   contain zero SIP INFO requests, while others can be expected to carry
   an occasional request).

14.7.9.  Info Package Security Considerations

   The MIME media type registations for the data blocks that can be
   carried using this SIP INFO package contains a discussion of the
   security and/or privacy considerations specific to that data block.
   The "Security Considerations" and "Privacy Considerations" sections
   of [TBD: THIS DOCUMENT] discuss security and privacy considerations
   of the data carried in vehicle-initiated emergency calls as described
   in that document.

14.7.10.  Implementation Details

   See [TBD: THIS DOCUMENT] for protocol details.

14.7.11.  Examples

   See [TBD: THIS DOCUMENT] for protocol examples.

15.  Acknowledgements

   We would like to thank Lena Chaponniere, Alissa Cooper, Stephen Edge,
   Christer Holmberg, Allison Mankin, and Dan Romascanu for their review
   and suggestions; Robert Sparks and Paul Kyzivat for their help with



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   the SIP mechanisms; Michael Montag, Arnoud van Wijk, Ban Al-Bakri,
   Wes George, Gunnar Hellstrom, and Rex Buddenberg for their feedback;
   and Ulrich Dietz for his help with earlier versions of the original
   version of this document.

16.  Changes from Previous Versions

   RFC Editor: Please remove this section prior to publication.

16.1.  Changes from draft-ietf-18 to draft-ietf-19

   o  Fixed various nits

16.2.  Changes from draft-ietf-17 to draft-ietf-18

   o  Added additional text to "Rate of Info Requests"
   o  Further corrected "content type" to "media type"

16.3.  Changes from draft-ietf-16 to draft-ietf-17

   o  Clarified that an INFO request is expected to have at least one
      VEDS, MSD or metadata/control body part
   o  Corrected "content type" to "media type"

16.4.  Changes from draft-ietf-14 to draft-ietf-15

   o  Moved VEDS text from Introduction to new Vehicle Data section
   o  Various clarifications and simplifications

16.5.  Changes from draft-ietf-13 to draft-ietf-14

   o  Body parts now always sent enclosed in multipart (even if only
      body part in SIP message) and hence always have a Content-
      Disposition of By-Reference
   o  Fixed typos.

16.6.  Changes from draft-ietf-11 to draft-ietf-13

   o  Fixed typos

16.7.  Changes from draft-ietf-10 to draft-ietf-11

   o  Clarifications suggested by Christer
   o  Corrections to Content-Disposition text and examples as suggested
      by Paul Kyzivat
   o  Clarifications to Content-Disposition text and examples to clarify
      that handling=optional is only used in the initial INVITE




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16.8.  Changes from draft-ietf-09 to draft-ietf-10

   o  Fixed errors in examples found by Dale in eCall draft
   o  Removed enclosing sub-section of INFO package registration section
   o  Added text per Christer and Dale's suggestions that the MSD and
      metadata/control blocks are sent in INFO with a Call-Info header
      field referencing them
   o  Other text changes per comments received from Christer and Ivo
      against eCall draft.

16.9.  Changes from draft-ietf-08 to draft-ietf-09

   o  Added INFO package registration for eCall.VEDS
   o  Moved <capabilities> element and other extension points back to
      eCall document so that extension points are in base spec (and also
      to get XML schema to compile)
   o  Text changes for clarification.

16.10.  Changes from draft-ietf-07 to draft-ietf-08

   o  Moved much of the metadata/control object from
      [I-D.ietf-ecrit-ecall] to this document as extensions
   o  Editorial clarifications and simplifications
   o  Moved "Call Routing" to be a subsection of "Call Setup"
   o  Deleted "Profile" section and moved some of its text into
      "Introduction"

16.11.  Changes from draft-ietf-06 to draft-ietf-07

   o  Minor editorial changes

16.12.  Changes from draft-ietf-05 to draft-ietf-06

   o  Added clarifying text regarding signed and encrypted data
   o  Additional informative text in "Migration to Next-Generation"
      section
   o  Additional clarifying text regarding security and privacy.

16.13.  Changes from draft-ietf-04 to draft-ietf-05

   o  Reworded security text in main document and in MIME registration
      for the VEDS object

16.14.  Changes from draft-ietf-03 to draft-ietf-04

   o  Added example VEDS object
   o  Additional clarifications and corrections
   o  Removed references from Abstract



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   o  Moved Document Scope section to follow Introduction

16.15.  Changes from draft-ietf-02 to draft-ietf-03

   o  Additional clarifications and corrections

16.16.  Changes from draft-ietf-01 to draft-ietf-02

   o  This document now refers to [I-D.ietf-ecrit-ecall] for technical
      aspects including the service URN; this document no longer
      proposes a unique service URN for non-eCall NG-ACN calls; the same
      service URN is now used for all NG-ACN calls including NG-eCall
      and non-eCall
   o  Added discussion of an NG-ACN call placed to a PSAP that doesn't
      support it
   o  Minor wording improvements and clarifications

16.17.  Changes from draft-ietf-00 to draft-ietf-01

   o  Added further discussion of test calls
   o  Added further clarification to the document scope
   o  Mentioned that multi-region vehicles may need to support other
      crash notification specifications such as eCall
   o  Minor wording improvements and clarifications

16.18.  Changes from draft-gellens-02 to draft-ietf-00

   o  Renamed from draft-gellens- to draft-ietf-
   o  Added text to Introduction to clarify that during a CS ACN, the
      PSAP call taker usually needs to listen to the data and transcribe
      it

16.19.  Changes from draft-gellens-01 to -02

   o  Fixed case of 'EmergencyCallData', in accordance with changes to
      [RFC7852]

16.20.  Changes from draft-gellens-00 to -01

   o  Now using 'EmergencyCallData' for purpose parameter values and
      MIME subtypes, in accordance with changes to [RFC7852]
   o  Added reference to RFC 6443
   o  Fixed bug that caused Figure captions to not appear








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17.  References

17.1.  Normative References

   [I-D.ietf-ecrit-ecall]
              Gellens, R. and H. Tschofenig, "Next-Generation Pan-
              European eCall", draft-ietf-ecrit-ecall-24 (work in
              progress), January 2017.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <http://www.rfc-editor.org/info/rfc2119>.

   [RFC5226]  Narten, T. and H. Alvestrand, "Guidelines for Writing an
              IANA Considerations Section in RFCs", BCP 26, RFC 5226,
              DOI 10.17487/RFC5226, May 2008,
              <http://www.rfc-editor.org/info/rfc5226>.

   [RFC6086]  Holmberg, C., Burger, E., and H. Kaplan, "Session
              Initiation Protocol (SIP) INFO Method and Package
              Framework", RFC 6086, DOI 10.17487/RFC6086, January 2011,
              <http://www.rfc-editor.org/info/rfc6086>.

   [RFC6838]  Freed, N., Klensin, J., and T. Hansen, "Media Type
              Specifications and Registration Procedures", BCP 13,
              RFC 6838, DOI 10.17487/RFC6838, January 2013,
              <http://www.rfc-editor.org/info/rfc6838>.

   [RFC6881]  Rosen, B. and J. Polk, "Best Current Practice for
              Communications Services in Support of Emergency Calling",
              BCP 181, RFC 6881, DOI 10.17487/RFC6881, March 2013,
              <http://www.rfc-editor.org/info/rfc6881>.

   [RFC7303]  Thompson, H. and C. Lilley, "XML Media Types", RFC 7303,
              DOI 10.17487/RFC7303, July 2014,
              <http://www.rfc-editor.org/info/rfc7303>.

   [RFC7852]  Gellens, R., Rosen, B., Tschofenig, H., Marshall, R., and
              J. Winterbottom, "Additional Data Related to an Emergency
              Call", RFC 7852, DOI 10.17487/RFC7852, July 2016,
              <http://www.rfc-editor.org/info/rfc7852>.

   [VEDS]     Advanced Automatic Crash Notification (AACN) Joint APCO/
              NENA Data Standardization Workgroup, , "Vehicular
              Emergency Data Set (VEDS) version 3", July 2012,
              <https://www.apcointl.org/resources/telematics/aacn-and-
              veds.html>.



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17.2.  Informative references

   [Bluetooth]
              Bluetooth Special Interest Group, , "Bluetooth
              Specifications", <https://https://www.bluetooth.com/
              specifications>.

   [RFC5012]  Schulzrinne, H. and R. Marshall, Ed., "Requirements for
              Emergency Context Resolution with Internet Technologies",
              RFC 5012, DOI 10.17487/RFC5012, January 2008,
              <http://www.rfc-editor.org/info/rfc5012>.

   [RFC5069]  Taylor, T., Ed., Tschofenig, H., Schulzrinne, H., and M.
              Shanmugam, "Security Threats and Requirements for
              Emergency Call Marking and Mapping", RFC 5069,
              DOI 10.17487/RFC5069, January 2008,
              <http://www.rfc-editor.org/info/rfc5069>.

   [RFC6443]  Rosen, B., Schulzrinne, H., Polk, J., and A. Newton,
              "Framework for Emergency Calling Using Internet
              Multimedia", RFC 6443, DOI 10.17487/RFC6443, December
              2011, <http://www.rfc-editor.org/info/rfc6443>.

   [RFC7378]  Tschofenig, H., Schulzrinne, H., and B. Aboba, Ed.,
              "Trustworthy Location", RFC 7378, DOI 10.17487/RFC7378,
              December 2014, <http://www.rfc-editor.org/info/rfc7378>.

   [triage-2008]
              National Center for Injury Prevention and Control, and
              Centers for Disease Control and Prevention,
              "Recommendations from the Expert Panel: Advanced Automatic
              Collision Notification and Triage of the Injured Patient",
              2008, <https://stacks.cdc.gov/view/cdc/5304/>.

   [triage-2011]
              National Center for Injury Prevention and Control, and
              Centers for Disease Control and Prevention, "Guidelines
              for field triage of injured patients: recommendations of
              the National Expert Panel on Field Triage", January 2012,
              <https://www.researchgate.net/journal/1545-8601_MMWR_Recom
              mendations_and_reports_Morbidity_and_mortality_weekly_repo
              rt_Recommendations_and_reports_Centers_for_Disease_Control
              >.








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Authors' Addresses

   Randall Gellens
   Core Technology Consulting

   Email: rg+ietf@randy.pensive.org


   Brian Rosen
   NeuStar, Inc.
   470 Conrad Dr
   Mars, PA  16046
   US

   Email: br@brianrosen.net


   Hannes Tschofenig
   Individual

   Email: Hannes.Tschofenig@gmx.net
   URI:   http://www.tschofenig.priv.at





























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