One document matched: draft-petrescu-its-cacc-sdo-02.xml


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     docName="draft-petrescu-its-cacc-sdo-02.txt"
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  <front>

    <title abbrev="C-ACC at SDOs and IP Gap Analysis">
      Cooperative Adaptive Cruise Control and Platooning at SDOs and
      Gap Analysis
    </title>

    <author initials='A.' surname="Petrescu" fullname='Alexandre Petrescu'
	    role="editor">
      <organization>CEA, LIST</organization>
      <address>
	<postal>
	  <street>
	    CEA Saclay
	  </street>
	  <city>
	    Gif-sur-Yvette
	  </city>
	  <region>
	    Ile-de-France
	  </region>
	  <code>
	    91190
	  </code>
	  <country>
	    France
	  </country>
	</postal>
	<phone>
	  +33169089223
	</phone>
	<email>
	  Alexandre.Petrescu@cea.fr
	</email>
      </address>
    </author>

    <author initials='J.' surname="Huang" fullname='James Huang'>
      <organization>Huawei Technologies</organization>
      <address>
    	<postal>
    	  <street></street>
    	  <city>Shenzhen</city>
    	  <region></region>
    	  <code></code>
    	  <country>China</country>
    	</postal>
    	<phone></phone>
    	<email>james.huang@huawei.com</email>
      </address>
    </author>

    <author initials='T.' surname="Ernst" fullname='Thierry Ernst'>
      <organization>
	Mines ParisTech
      </organization>
      <address>
	<postal>
	  <street>
	  </street>
	  <city>
	    Paris
	  </city>
	  <region>
	  </region>
	  <code>
	    75006
	  </code>
	  <country>
	    France
	  </country>
	</postal>
	<phone>
	</phone>
	<email>
	  Thierry.Ernst@mines-paristech.fr
	</email>
      </address>
    </author>

    <author initials='R.' surname="Buddenberg" fullname="Rex Buddenberg">
      <organization>
	" "
      </organization>
      <address>
	<postal>
	  <street>
	  </street>
	  <city>
	  </city>
	  <region>
	  </region>
	  <code>
	  </code>
	  <country>
	    US
	  </country>
	</postal>
	<phone>
	</phone>
	<email>
	  buddenbergr@gmail.com
	</email>
      </address>
    </author>    

    <date/>

    <!-- Meta-data Declarations -->

    <area>Internet</area>

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    <keyword>
      C-ACC, Platooning, V2V, Vehicle-to-Vehicle communications, LTE
      D2D, device-to-device communications
    </keyword>

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    <abstract>
      <t>
	This document describes the use-cases of Cooperative Adaptive
	Cruise Control, and Platooning, as defined by several
	Standards Development Organizations such as ETSI, IEEE P1609,
	SAE, 3GPP, ISO and FirstNet.
      </t>
      <t>
	C-ACC and Platooning involve concepts of direct
	vehicle-to-vehicle, and device-to-device communications, which
	are developped at least by 3GPP and precursory by the METIS EU
	project.  They are illustrated very clearly in emergency
	settings such as FirstNet.
      </t>
      <t>
	IP messages - instead of link-layer messages - are pertinent
	for C-ACC and Platooning use-cases because applications for
	road safety such as WAZE, iRezQ and Coyote (currently
	involving infrastructure) are IP messages, and proved
	succesful in deployments.  Applications such as Sentinel are
	direct between vehicles but are not IP, currently.
      </t>

    </abstract>
  </front>

  <middle>
    <section title="Introduction">
	<t>
	  Cooperative Adaptive Cruise Control and Platooning are two
	  use-cases described recently at particular Standards
	  Development Organizations.  C-ACC is understood as a
	  formation of chains of automobiles following each other at
	  constant speed, in an automated manner.  This is to offer
	  more comfort for human drivers on long journeys on straight
	  roads.
	</t>
	<t>
	  Simple 'cruise control' was the automation of speed
	  maintenance at a single automobile (increase torque if
	  uphill, smoothly brake downhill, such as to maintain
	  constant speed).  The term "Adaptive Cruise Control" was
	  used earlier in related ISO standards.  The concept of C-ACC
	  aims at the same level of automation but in a cooperative
	  manner between several vehicles: while in CC mode, when a
	  vehicle in front slowly decelerates, this vehicle will also
	  do, such as to maintain distance, and relieve driver from
	  taking control over.
	</t>
	<t>
	  Platooning is a concept related to larger vehicles following
	  each other.  The goal in this case is more than just comfort
	  - large gains are expected in terms of gas consumption: when
	  large vehicles can follow each other at small distance the
	  air-drag is much lower, reducing gas consumption, tyre use,
	  and more.
	</t>

	<t>
	  Both C-ACC and Platooning must rely on data packet exchanges
	  between vehicles (in addition to more immediate indices like
	  signal echoes - radars and cameras).  These exchanges may
	  happen in a direct manner (direct vehicle to vehicle
	  communications) or with assistance from a fixed
	  communication infrastructure
	  (vehicle-to-infrastructure-to-vehicle communications).
	</t>

	<t>
	  This document presents the C-ACC and Platooning use-cases as
	  described at ETSI, IEEE, SAE, ISO, 3GPP and more.  These
	  use-cases are widely accepted as Vehicle-to-Vehicle
	  applications.
	</t>

	<t>
	  In emergency settings the concepts of direct
	  vehicle-to-vehicle communications are of paramount
	  importance.  FirstNet, an overarching example described
	  later in this document, covers V2V, V2I and V2I2V
	  communication needs, together with strong security
	  requirements.
	</t>

	<t>
	  In the market, several systems for vehicular communications
	  have demonstrated a number of benefits in the context of
	  vehicle-to-vehicle communications.  The Sentinel system is
	  used between vehicles to warn each other about approach; the
	  WAZE application on smartphones created a community where
	  users influence others about the route choice; the iRezQ and
	  Coyote applications communicate between vehicles, via
	  infrastructure, about route risks.
	</t>
	
	<!-- <t>  -->
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	<t>
	  In <xref target="I-D.petrescu-ipv6-over-80211p"/> the use of
	  IPv6 over 802.11p is described.  This link layer is
	  potentially used in direct vehicle-to-vehicle
	  communications.  It is obviously not the only link layer
	  pertinent for V2V.
	</t>
	
    </section>
	
    <section title="Terminology">
      <t>
	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
	<xref target="RFC2119">RFC 2119</xref>.
      </t>
      <t>
	C-ACC: Cooperative Adaptive Cruise Control.
      </t>
      <t>
	V2V: Vehicle-to-Vehicle communications.
      </t>
    </section>

    <section anchor="etsi"
	     title="ETSI ITS C-ACC and Platooning use-case and reqs">
      <t>
	ETSI Technical Committee Intelligent Transportation Systems
	(ETSI TC ITS) is responsible for the development and
	maintenance of standards, specifications and other reports on
	the implementation of V2V communications in Cooperative
	ITS. Its scope extends from the wireless access (excluding
	issues in radio frequency) to generic services and
	corresponding applications.  Security and tests specifications
	are also covered.  This responsibility is reflected in the
	organization with five working groups that make up the
	committee. Among them, WG1 is responsible of the facilities
	and applications needs.
      </t>
      <t>
	Under the EU Mandate M/453, TC ITS has developed a minimum set
	of standards (Release 1) for systems interoperability during
	initial deployment.  The list of standards and specifications
	are provided in the publicly available report ETSI TR 101
	607. A second release of the standards is being prepared. It
	should support more complex use case, possible integration
	with other technologies as well as a more elaborate
	consideration of access networks other than the ITS-G5
	(European profile of IEEE 802.11p).  The TC ITS WG1 is
	currently working on two separate work items for
	pre-standardization studies on C-ACC (DTR/ITS-00164) and
	Platooning (DTR/ITS-00156).  The scope of the target technical
	reports is to describe the relevant use cases that could be
	enabled by Cooperative ITS, to survey the existing related
	standards and to identify what new features and standards are
	needed to support these use cases.
      </t>
    </section>

    <section anchor="IEEE" title="IEEE P1609 perspective on
				  communications for C-ACC and Platooning">
      <t>
	One perspective from IEEE P1609 is that Cooperative Adaptive
	Cruise Control (CACC) represents an "application".  An
	application is typically software whose communication needs
	are situated at the upper layers of a communication stack -
	e.g. the Application Layer.  As such it is little relevant to
	IEEE P1609; P1609 is concerned more with physical, data-link
	and network communication layers.  On another hand, a
	perspective well considered in IEEE P1609 is that C-ACC and
	Platooning may be more relevant to the Society of Automotive
	Engineers.
      </t>
    </section>

    <section anchor="SAE" title="SAE perspective on C-ACC and Platooning">
      <t>
	The Society of Automotive Engineers (SAE) concerns itself with
	data exchanges and host system requirements for applications.
	The SAE DSRC Technical Committee (DSRC: Dedicated Short-Range
	Communications) is working on C-ACC within the Cooperative
	Vehicle Task Force.  In addition, the SAE On-Road Vehicle
	Automation Committee is working on a use-case relevant to
	C-ACC (under development) towards realization of a reference
	architecture.
      </t>
      <t>
	The SAE DSRC TC activities are in cooperative agreement to
	ETSI ITS WG1, as there are information exchanges between the
	two bodies.
      </t>
    </section>

    <section title="3GPP SDO and EU projects using LTE Device-to-Device concepts" 
	     anchor="pp"	       
	     >

      <section title="3GPP">
        <t>
	  Proximity Service (ProSe) allows a UE to discover and
	  communicate with other UEs that are in proximity directly or
	  with the network assistance. This may also be called as
	  Device-to-Device (D2D) communication. ProSe is intended for
	  purposes such as public security, network offloading, etc
	  <xref target="GPP-TR-22-803"/>.
	</t>

        <t>
	  The ProSe Communication path could use E-UTRAN or WLAN.
	  In the case of WLAN, only ProSe-assisted WLAN direct
	  communication (i.e. when ProSe assists with connection
	  establishment management and service continuity) is
	  considered <xref target="GPP-TS-22-278"/>.
	</t>

        <t>
	  The work on ProSe is initiated in 3GPP Release 12. Some
	  enhancements are being added in Release 13,
	  e.g. Restricted ProSe Discovery. Some use cases are
	  identified in <xref target="GPP-TR-22-803"/>, but most of
	  which are intended for common mobile users, e.g. walking
	  people, not for vehicles moving at high speed, for example
	  the latency in ProSe communication may be a problem for
	  V2X.
	</t>

        <t>
	  Although ProSe does not support V2X communication before
	  Release 14, but it has some very good characteristics
	  which makes it a good candidate for V2X besides
	  DSRC. ProSe communication does not have to go through the
	  EPC, which will significantly reduce the latency. ProSe
	  also support group and broadcast communication by means of
	  a common communication path established between the UEs.
	</t>

        <t>
	  There are some efforts at 3GPP Release 14, trying to
	  address V2X communication. The efforts are proposed by
	  experts in the industry, and may be subject to
	  change. These efforts include the following:

	  <list style='numbers'>
            <t>
	      To address the V2X use cases in 3GPP. The use cases may
	      have been defined by other SDOs, e.g. ETSI ITS, 3GPP can
	      reference to them. Requirements for V2X communication
	      should also be considered, for example network delay,
	      packet loss rate, etc. <xref target="METIS-D1.1"/>
	      already propose some requirements, but those are
	      intended for future mobile network, which may be too
	      critical for LTE.
	    </t>

            <t>
	      To address V2X applications and messages. The messages
	      may include message defined in SAE J2735, ETSI
	      Cooperative Awareness Message (CAM) and ETSI
	      Decentralized Environmental Notification Message (DeNM).
	      The messages defined by different SDOs might be similar
	      to each other.
	    </t>

            <t>
	      Study of possibility to add enhancements to ProSe, and
	      to make it able to support and enhance DSRC.
	    </t>

            <t>
	      Study of using existing LTE technologies for
	      unicast/multicast/broadcast communication.
	    </t>
	  </list>
	</t>

        <t>
	  The above are just some examples, not an exhaustive list.
	</t>

	<t>
	  <xref target="GPP-TR-22-885"/> studies many V2X services
	  using LTE.  These services include V2V communication
	  (e.g. Cooperative Adaptive Cruise Control, Forwarding
	  Collision Warning, etc), V2I/V2N communication (e.g. Road
	  Safety Services) and vehicle to pedestrian
	  communication. The services' pre-condition, service flow,
	  post-condition, including some network communication
	  requirements, such as delay, messages frequency and message
	  size, are ayalyzed.
	</t>

	<t>
	  In <xref target="GPP-TR-22-885"/>, Cooperative Adaptive
	  Cruise Control (CACC) allows a vehicle to join a group of
	  CACC vehicles, and the benefits are to improve road
	  congestion and fuel efficiency. Member vehicles of CACC
	  group should periodically broadcast messages including the
	  CACC group information, such as speed and gap policies, etc.
	  If a vehicle outside the group wants to join, it should send
	  a request to the group.  If a member of the CACC group
	  accepts the request, it should send a confirm message and
	  provide necessary distance gap; and members of the group
	  will update their group information. When a Member wants to
	  leave the CACC group, it should broadcast a goodbye message,
	  and the driver assumes control of the vehicle.
	</t>
	
      </section>

      <section title="METIS">
        <t>
	  METIS is co-funded by the European Commission as an
	  Integrated Project under the Seventh Framework Programme for
	  research and development (FP7).
	</t>

        <t>
	  METIS defines test cases and requirements of "Traffic
	  safety and efficiency", as depicted in <xref
	  target="METIS-D1.1"/>, which is intended for 5G in 2020
	  but may also be applicable for LTE and beyond.
	</t>

        <t>
	  The use cases include:
	  <list style='numbers'>
	    <t>
	      Dangerous situation that can be avoided by means of V2V
	      communications.
	    </t>	   
            <t>
	      Dangerous situation with vulnerable road users
	      (i.e. pedestrians, cyclists,...) that can be avoided by
	      means of V2D communications. "D" can denote any cellular
	      device that the vulnerable road user may carry
	      (e.g. smart phone, tablet, sensor tag).
	    </t>
            <t>
	      Assistance services that can improve traffic efficiency
	      by means of V2X communications, e.g. traffic sign
	      recognition and green light assistance.
	    </t>
	    <t>
	      Platooning (or road trains) in an autonomous manner to
	      increase traffic flows and reduce fuel consumption and
	      emissions.
	    </t>
            <t>
	      Highly automated vehicles.
	    </t>
	  </list>	
	</t>

        <t>
	  To support the above use cases, METIS works out the
	  corresponding network requirements, such as E2E latency
	  should be within 5ms, required data rates for various
	  scenarios, service ranges in highway/rural/urban
	  scenarios, etc.
	</t>
      </section>

    </section>

    <section anchor="iso" title="ISO perspective on V2V">
      <t>
	The International Standards Organization's Technical Committee
	204 "Intelligent transport systems" (ISO TC204, in short) has
	specified a communication architecture known as the "ITS
	station reference communication architecture" <xref
	target='ISO-21217'/>.  This communication architecture covers
	all layers (access technologies, network, transport,
	facilities and applications) of a typical communications
	protocol stack.  It is designed to accommodate communications
	between ITS stations engaged in ITS services.  ITS stations
	can be deployed in vehicles of any type, roadside
	infrastructure (traffic lights, variable message signs, toll
	road gantries, etc.), urban infrastructure (parking gates, bus
	stops, etc.)  nomadic devices (smartphones, tablets) and
	control centers (traffic control center, emergency call
	centers, data centers and services centers).  The ITS stations
	can be distributed in several nodes (e.g. an in-vehicle
	gateway and a set of hosts attached to the internal in-vehicle
	network).  The ITS station architecture is designed to support
	many kinds of wired and wireless access technologies
	(vehicular WiFi 802.11p, urban WiFi 802.11b/g/n/ac/ad;
	cellular networks; satellite; infra-red, LiFi, millimeter
	wave, etc.)
      </t>
      <t>
	The ISO ITS station architecture can thus support both
	broadcast and unicast types of communication,
	vehicle-to-infrastructure communications (road infrastructure
	using e.g. WiFi, or cellular infrastructure using e.g. 3G/4G)
	and, most notably, direct vehicle-to-vehicle communications.
      </t>
      <t>
	The architecture includes the possibility to communicate using
	IPv6 <xref target='ISO-21210'/> or non-IP (ISO FNTP, currently
	being harmonized with IEEE WAVE).
      </t>
      <t>
	The ISO TC204/WG14 (Work Group 14 "Vehicle/Roadway Warning and
	Control Systems") is developing a draft of international
	standard for C-ACC systems.  The focus is on vehicular system
	control, rather than on communication media.  The potential
	work item is in an early stage of development; it may describe
	performance requirements or validation through test
	procedures.  It is considered that "C-ACC" to be an expansion
	to the existing ACC concepts which have been previously
	described in the document ISO 15622 "Adaptive Cruise Control
	Systems".  The potential C-ACC work item may require the
	specific involvement of Vehicle-to-Vehicle communications and
	other types of communications (I2V and more), in addition to
	requiring active sensing involving radars and camera systems.
      </t>
    </section>
    
    <section title="ISO-IEEE Harmonization">
      <t>
	The intent is to harmonize the IEEE 1609 and ISO FAST
	protocols at 5.9GHz to avoid having to support
	region-dependent protocols (e.g. different protocols in Europe
	and the US), and this intention is not dependent on any
	particular application or service.
      </t>

      <t>
	For example, the IEEE 1609.3 WSMP and WSA messages have
	recently been harmonized with ISO 29281-1 FNTP and ISO 24102-5
	FSAP.
      </t>

      <t>
	C-ACC and Platooning are (C-)ITS services that will get
	deployed as ITS applications involving ITS application
	instances being installed on ITS stations in vehicles.  These
	applications can and will make use of any and all available
	ITS station communication services (network and transport
	protocols, data link layer protocols, and physical layer
	protocols) that have the necessary characteristics/properties
	(e.g. V2V, low-latency, moderate bandwidth, etc.) to achieve
	their goals.  The IEEE 1609 and ISO protocols and
	communication services, whether or not they are ultimately
	"harmonized", can be used by either or both of these ITS
	applications as they generally meet the requirements for these
	apps.
      </t>

      <t>
	Some communication tasks in C-ACC and Platooning will use
	IPv6, whereas others will not.  For example some vendors of
	WAVE devices and ITS station units consider the use of the
	short messages protocol (not IPv6) for C-ACC and Platooning
	scenarios.
      </t>
    </section>

    <section anchor="firstnet" title="FirstNet EMS use of LTE and IP
				      in V2I2V">
      <t>
	FirstNet is a corporation housed inside the US Department of
	Commerce.  It gets capitalization budget from, among other
	sources, sale of spectrum by the US FCC.  It gets operating
	budget from sale of services to state emergency services
	entities.
      </t>

      <t>
	The specific use-cases for FirstNet include
	vehicle-to-vehicle, vehicle-to-infrastructure and
	vehicle-to-infrastructure-to-vehicle communications using in
	certain cases LTE and IP:
	<list style='numbers'>
	  <t>
	    Emergency communications to vehicles from government
	    entities conveying, for example: weather warnings, road
	    conditions, evacuation orders.  The government entities
	    might include PSAPs or mobile vehicles such as police
	    cruisers.
	  </t>
          <t>
	    Instrumented emergency services vehicles such as
	    ambulances.  An example is the ability to telemeter
	    casualty (patient) data from sensors attached to the
	    casualty to a hospital emergency room.
	  </t>
	  <t>
	    Emergency communications from vehicles' occupants to
	    government entities such as Public Safety Access Points
	    (PSAPs, also known as 911 operators in US).
	  </t>
	</list>
      </t>

      <t>
	The National Public Safety Telecommunications Council
	describes FirstNet as an emergency communications system
	(largely viewed through the prism of the familiar Land Mobile
	Radio systems most emergency services use.)  The cellular
	telephone industry views FirstNet as supplementary to an
	existing commercial cellphone system (e.g. reusing the same
	towers and backhaul).  Perhaps a better view of FirstNet is as
	an extension of the Internet to emergency services vehicles
	(including foot-borne).
      </t>

      <t>
	It is clear that FirstNet overlaps to a large extent to the
	concepts that have been discussed in vehicle-to-vehicle
	communications for other purposes.
      </t>

      <t>
	FirstNet has not been clear about its communication technology
	choices to date.  But LTE has been discussed as the most
	likely layer 2 protocol.  A segregated segment of spectrum in
	the 700MHz band has been set aside by Congressional action for
	emergency services and control of that spectrum has been
	passed to FirstNet.  There appear to be no new protocols,
	development of which is fostered by FirstNet.  Several
	Internet applications would need rework to handle high
	availability, security and assured access needs of emergency
	services.
      </t>

    </section>    

    <section anchor="apps" title="Internet apps: WAZE, iRezQ, Coyote, Sentinel">
      <t>
	Applications using the Internet have been developped in the
	particular context of vehicular communications.  These
	applications are designed for parties situated in
	vehicles.  Their profile is less of client-server kind, but
	more of peer-to-peer kind (vehicle to vehicle).
      </t>
      <t>
	Some use vehicle-to-infrastructure-to-vehicle IP paths,
	whereas others involve direct vehicle-to-vehicle paths
	(without infrastructure).
      </t>
      <t>
	These applications are described in more detail in
	draft-liu-its-scenario-00.txt issued on March 9th, 2015,
	authored by Dapeng Liu.
      </t>
	  
    </section>

    <section anchor="gap" title="Gap Analysis">
      <t>
	It is generally agreed that an entire IP network is embedded
	in an automobile.  The embedded network is formed by at least
	two (and generally up to 5) distinct IP subnets.  In each of
	the subnets several IP-addressable computers are currently
	enabled with IP stacks.
      </t>
      <t>
	The realization of V2V communications can happen by connecting
	together two such embedded networks, each carried by a
	distinct vehicle.  With a direct connection, an IP Router in
	one vehicle connects to an IP Router in another vehicle
	nearby.  The maximum distance between two such vehicles is
	dictated by the link layer technology (e.g., with IEEE 802.11p
	OCB mode the distance may be up to 800 metres).  On another
	hand, an indirect connection may involve the use of a
	Road-Side Unit fixed along the road, or a longer IP path
	through a cellular network.  It is expected that the shortest
	latencies to be obtained with the most straightforward
	(direct) connections rather than through-fixed-RSU
	through-cellular.
      </t>
      <t>
	When two vehicles are connected to each other in this way, an
	IP subnet is formed between the egress interfaces of Router
	embedded in vehicles.  There are several ways in which the IP
	path can be established across this 1-hop subnet.
      </t>
      <section title="Neighbor Discovery protocol">
	<t>
	  Routers exchange Router Advertisement messages.  An RA
	  message contains prefixes announced to be valid on one link.
	  On another hand, the prefix announced by an RA can not be
	  equal to the prefix of a same router but of one of its other
	  interfaces.  And this represents the gap of the ND protocol
	  - it can not realize V2V topologies.
	</t>
      </section>
      <section title="Mobile IP protocol">
	<t>
	  There are two modes of operation of a V2V topology.  With a
	  link technology like IEEE 802.11b it is possible that one
	  vehicle attaches to another vehicle in "Access Point" mode,
	  or alternatively in "ad-hoc" mode.  In "Access Point" mode
	  (or Client-Server), the first vehicle allocates an address,
	  and potentially a prefix, to the second vehicle.  This
	  latter may then use the Mobile IP protocol to inform the
	  first vehicle about is in-car prefix (use a Binding Update
	  message as if the Access Point vehicle were a Correspondent
	  Node).  The gap is in that currently the Mobile IP protocol
	  is not fully specified to send BUs in that way.
	</t>
      </section>
      <section title="AODV protocol">
	<t>
	  The AODV protocol is a routing protocol used to build and
	  find IP paths in a MANET network.  However, this protocol
	  does not take into account default routes.  Default routes
	  are extensively used in current networks carried in
	  vehicles.  The good administration of these routes simplify
	  to a large extent the routing in such networks.  This
	  represents a gap.
	</t>
      </section>

    </section>

    <section anchor="Security" title="Security Considerations">
      <t>
	All government-to-vehicle and vehicle-to-government
	communications require authenticity; there will be no
	exceptions.
      </t>

      <t>
	Some, but not all, communications from government-to-vehicle
	and vehicle-to-government require confidentiality (some of
	these requirements, such as medical data, have the force of
	law, many have custom or respect as the requirements base).
      </t>

      <t>
	These requirements pertain to the content.
      </t>

    </section>
    

    <section anchor="IANA" title="IANA Considerations">
      <t>
	mandatory
      </t>
    </section>

    <section anchor="Contributors"
	     title="Contributors">
      <t>
	Jim Misener (Qualcomm, SAE DSRC TC Chair), Masanori Misumi
	(Mazda, ISO TC204/WG14 Convenor), Michelle Wetterwald
	(FBConsulting, ETSI active member), Hans-Joachim Fischer,
	Richard "Dick" Roy.
      </t>
    </section>

    <!-- <section anchor="Acknowledgements" -->
    <!-- 	     title="Acknowledgements"> -->
    <!--   <t> -->
    <!-- 	The authors would like to acknowledge . -->
    <!--   </t> -->
    <!-- </section> -->
    
  </middle>

  <!--  *****BACK MATTER ***** -->

  <back>

    <references title="Normative References">
      &RFC2119;
    </references>

    <references title="Informative References">
      &DRAFT-IPv6-over-11p;
      <!-- &DRAFT-liu;  -->

      <reference anchor='METIS-D1.1'>
        <front>
          <title>
	    Scenarios, requirements and KPIs for 5G mobile and
	    wireless system
	  </title>

          <author initials='M.' surname='Fallgren'
		  fullname='Mikael Fallgren'>
            <organization>
	      Ericsson AB
	    </organization>
          </author>

          <author initials='B.' surname='Timus' fullname='Bogdan Timus'>
            <organization>
	      Ericsson AB
	    </organization>
          </author>
	  
          <date year='2013' month='April' />
        </front>

        <format type="PDF"
		target='https://www.metis2020.com/wp-content/uploads/deliverables/METIS_D1.1_v1.pdf' />
      </reference>

      <reference anchor="GPP-TR-22-803">
        <front>
          <title>
	    Feasibility study for Proximity Services (ProSe)
	  </title>
          <author initials='' surname='' fullname=''>
            <organization>
	      3GPP
	    </organization>
          </author>
          <date year='2013' month='June' />
        </front>

        <format type="zip"
		target='http://www.3gpp.org/ftp/specs/archive/22_series/22.803/22803-c20.zip' />
      </reference>

      <reference anchor='GPP-TS-22-278'>
        <front>
          <title>
	    Service requirements for the Evolved Packet System (EPS)
	  </title>
          <author initials='' surname='' fullname=''>
            <organization>
	      3GPP
	    </organization>
          </author>
	  
          <date year='2014' month='December' />
        </front>
        <format type="zip"
		target='http://www.3gpp.org/ftp/specs/archive/22_series/22.278/22278-d20.zip' />
      </reference>

      <reference anchor='GPP-TR-22-885'>
        <front>
          <title>
	    Study on LTE Support for V2X Services
	  </title>
          <author initials='' surname='' fullname=''>
            <organization>
	      3GPP
	    </organization>
          </author>
	  
          <date year='2015' month='April' />
        </front>
        <format type=""
		target='' />
      </reference>

      <reference anchor='ISO-21217'>
        <front>
          <title>
	    21217: TC ITS - WG CALM - Architecture -
	    International Standard
	  </title>
          <author initials='' surname='' fullname=''>
            <organization>
	      ISO
	    </organization>
          </author>
	  
          <date year='2014' month='' />
        </front>
        <format type=""
		target='http://www.iso.org/iso/catalogue_detail.htm?csnumber=61570' />
      </reference>

      <reference anchor='ISO-21210'>
        <front>
          <title>
	    21210: TC ITS - WG CALM - IPv6 Networking -
	    International Standard
	  </title>
          <author initials='' surname='' fullname=''>
            <organization>
	      ISO
	    </organization>
          </author>
	  
          <date year='2014' month='' />
        </front>
        <format type=""
		target='http://www.iso.org/iso/catalogue_detail.htm?csnumber=46549' />
      </reference>      

    </references>


    <section anchor='changelog'
	     title='ChangeLog'>
      <t>
	The changes are listed in reverse chronological order, most
	recent changes appearing at the top of the list.
      </t>

      <t>
	From -01 to -02:
	<list style='symbols'>
	  <t>
	    Added perspectives on C-ACC and Platooning from ETSI, SAE,
	    IEEE P1609 and ISO-IEEE Harmonization.  Updated the
	    perspective from ISO.
	  </t>
	  <t>
	    Added Gap Analysis: what are the gaps between what
	    existing protocols ND, Mobile IP and AODV can do and what
	    is needed to realize a C-ACC and Platooning use-case with
	    a V2V topology?
	  </t>
	</list>	
      </t>
      
      <t>
	From nil to draft-petrescu-its-cacc-sdo-00.xml:
	<list style='symbols'>
	  <t>
	    initial version
	  </t>
	</list>	
      </t>      	
      
    </section>

  </back>
</rfc>

PAFTECH AB 2003-20262026-04-23 16:30:24