draft-ietf-ipwave-vehicular-networking-12.txt   draft-ietf-ipwave-vehicular-networking-13.txt 
IPWAVE Working Group J. Jeong, Ed. IPWAVE Working Group J. Jeong, Ed.
Internet-Draft Sungkyunkwan University Internet-Draft Sungkyunkwan University
Intended status: Informational October 3, 2019 Intended status: Informational January 6, 2020
Expires: April 5, 2020 Expires: July 9, 2020
IP Wireless Access in Vehicular Environments (IPWAVE): Problem Statement IPv6 Wireless Access in Vehicular Environments (IPWAVE): Problem
and Use Cases Statement and Use Cases
draft-ietf-ipwave-vehicular-networking-12 draft-ietf-ipwave-vehicular-networking-13
Abstract Abstract
This document discusses the problem statement and use cases of IP- This document discusses the problem statement and use cases of
based vehicular networking for Intelligent Transportation Systems IPv6-based vehicular networking for Intelligent Transportation
(ITS). The main scenarios of vehicular communications are vehicle- Systems (ITS). The main scenarios of vehicular communications are
to-vehicle (V2V), vehicle-to-infrastructure (V2I), and vehicle-to- vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), and
everything (V2X) communications. First, this document explains use vehicle-to-everything (V2X) communications. First, this document
cases using V2V, V2I, and V2X networking. Next, it makes a problem explains use cases using V2V, V2I, and V2X networking. Next, it
statement about key aspects in IP-based vehicular networking, such as makes a problem statement about key aspects in IPv6-based vehicular
IPv6 Neighbor Discovery, Mobility Management, and Security & Privacy. networking, such as IPv6 Neighbor Discovery, Mobility Management, and
For each key aspect, this document specifies requirements in IP-based Security & Privacy. For each key aspect, this document specifies
vehicular networking, and suggests the direction of solutions requirements for IPv6-based vehicular networking.
satisfying those requirements.
Status of This Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
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This Internet-Draft will expire on April 5, 2020. This Internet-Draft will expire on July 9, 2020.
Copyright Notice Copyright Notice
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Use Cases . . . . . . . . . . . . . . . . . . . . . . . . . . 5 3. Use Cases . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.1. V2V . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 3.1. V2V . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3.2. V2I . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 3.2. V2I . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3.3. V2X . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 3.3. V2X . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
4. Vehicular Networks . . . . . . . . . . . . . . . . . . . . . 8 4. Vehicular Networks . . . . . . . . . . . . . . . . . . . . . 9
4.1. Vehicular Network Architecture . . . . . . . . . . . . . 9 4.1. Vehicular Network Architecture . . . . . . . . . . . . . 10
4.2. V2I-based Internetworking . . . . . . . . . . . . . . . . 11 4.2. V2I-based Internetworking . . . . . . . . . . . . . . . . 13
4.3. V2V-based Internetworking . . . . . . . . . . . . . . . . 13 4.3. V2V-based Internetworking . . . . . . . . . . . . . . . . 15
5. Problem Statement . . . . . . . . . . . . . . . . . . . . . . 14 5. Problem Statement . . . . . . . . . . . . . . . . . . . . . . 16
5.1. Neighbor Discovery . . . . . . . . . . . . . . . . . . . 15 5.1. Neighbor Discovery . . . . . . . . . . . . . . . . . . . 16
5.1.1. Link Model . . . . . . . . . . . . . . . . . . . . . 16 5.1.1. Link Model . . . . . . . . . . . . . . . . . . . . . 18
5.1.2. MAC Address Pseudonym . . . . . . . . . . . . . . . . 17 5.1.2. MAC Address Pseudonym . . . . . . . . . . . . . . . . 19
5.1.3. Routing . . . . . . . . . . . . . . . . . . . . . . . 18 5.1.3. Routing . . . . . . . . . . . . . . . . . . . . . . . 20
5.2. Mobility Management . . . . . . . . . . . . . . . . . . . 19 5.2. Mobility Management . . . . . . . . . . . . . . . . . . . 20
6. Security Considerations . . . . . . . . . . . . . . . . . . . 20 6. Security Considerations . . . . . . . . . . . . . . . . . . . 21
7. Informative References . . . . . . . . . . . . . . . . . . . 21 7. Informative References . . . . . . . . . . . . . . . . . . . 23
Appendix A. Changes from draft-ietf-ipwave-vehicular- Appendix A. Changes from draft-ietf-ipwave-vehicular-
networking-11 . . . . . . . . . . . . . . . . . . . 27 networking-12 . . . . . . . . . . . . . . . . . . . 29
Appendix B. Acknowledgments . . . . . . . . . . . . . . . . . . 28 Appendix B. Acknowledgments . . . . . . . . . . . . . . . . . . 29
Appendix C. Contributors . . . . . . . . . . . . . . . . . . . . 28 Appendix C. Contributors . . . . . . . . . . . . . . . . . . . . 29
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 30 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 32
1. Introduction 1. Introduction
Vehicular networking studies have mainly focused on improving safety Vehicular networking studies have mainly focused on improving safety
and efficiency, and also enabling entertainment in vehicular and efficiency, and also enabling entertainment in vehicular
networks. The Federal Communications Commission (FCC) in the US networks. The Federal Communications Commission (FCC) in the US
allocated wireless channels for Dedicated Short-Range Communications allocated wireless channels for Dedicated Short-Range Communications
(DSRC) [DSRC] in the Intelligent Transportation Systems (ITS) with (DSRC) [DSRC] in the Intelligent Transportation Systems (ITS) with
the frequency band of 5.850 - 5.925 GHz (i.e., 5.9 GHz band). DSRC- the frequency band of 5.850 - 5.925 GHz (i.e., 5.9 GHz band). DSRC-
based wireless communications can support vehicle-to-vehicle (V2V), based wireless communications can support vehicle-to-vehicle (V2V),
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Physical Layer (L1) and Data Link Layer (L2) issues are addressed in Physical Layer (L1) and Data Link Layer (L2) issues are addressed in
IEEE 802.11p [IEEE-802.11p] for the PHY and MAC of the DSRC, while IEEE 802.11p [IEEE-802.11p] for the PHY and MAC of the DSRC, while
IEEE 1609.2 [WAVE-1609.2] covers security aspects, IEEE 1609.3 IEEE 1609.2 [WAVE-1609.2] covers security aspects, IEEE 1609.3
[WAVE-1609.3] defines related services at network and transport [WAVE-1609.3] defines related services at network and transport
layers, and IEEE 1609.4 [WAVE-1609.4] specifies the multi-channel layers, and IEEE 1609.4 [WAVE-1609.4] specifies the multi-channel
operation. IEEE 802.11p was first a separate amendment, but was operation. IEEE 802.11p was first a separate amendment, but was
later rolled into the base 802.11 standard (IEEE 802.11-2012) as IEEE later rolled into the base 802.11 standard (IEEE 802.11-2012) as IEEE
802.11 Outside the Context of a Basic Service Set (OCB) in 2012 802.11 Outside the Context of a Basic Service Set (OCB) in 2012
[IEEE-802.11-OCB]. [IEEE-802.11-OCB].
Along with these WAVE standards, IPv6 [RFC8200] and Mobile IP Along with these WAVE standards, IPv6 [RFC8200] and Mobile IPv6
protocols (e.g., MIPv4 [RFC5944], MIPv6 [RFC6275], and Proxy MIPv6 protocols (e.g., Mobile IPv6 (MIPv6) [RFC6275], and Proxy MIPv6
(PMIPv6) [RFC5213][RFC5844]) can be applied to vehicular networks. (PMIPv6) [RFC5213]) can be applied to vehicular networks. In
In addition, ISO has approved a standard specifying the IPv6 network addition, ISO has approved a standard specifying the IPv6 network
protocols and services to be used for Communications Access for Land protocols and services to be used for Communications Access for Land
Mobiles (CALM) [ISO-ITS-IPv6]. Mobiles (CALM) [ISO-ITS-IPv6].
This document describes use cases and a problem statement about IP- This document describes use cases and a problem statement about
based vehicular networking for ITS, which is named IP Wireless Access IPv6-based vehicular networking for ITS, which is named IPv6 Wireless
in Vehicular Environments (IPWAVE). First, it introduces the use Access in Vehicular Environments (IPWAVE). First, it introduces the
cases for using V2V, V2I, and V2X networking in ITS. Next, it makes use cases for using V2V, V2I, and V2X networking in ITS. Next, it
a problem statement about key aspects in IPWAVE, namely, IPv6 makes a problem statement about key aspects in IPWAVE, namely, IPv6
Neighbor Discovery, Mobility Management, and Security & Privacy. For Neighbor Discovery (ND), Mobility Management (MM), and Security &
each key aspect of the problem statement, this document specifies Privacy (SP). For each key aspect of the problem statement, this
requirements in IP-based vehicular networking, and proposes the document specifies requirements for IPv6-based vehicular networking.
direction of solutions fulfilling those requirements. This document This document is intended to motivate development of key protocols
is intended to motivate development of key protocols for IPWAVE. for IPWAVE.
2. Terminology 2. Terminology
This document uses the following definitions: This document uses the terminology described in [RFC8691]. In
addition, the following terms are defined below:
o Class-Based Safety Plan: A vehicle can make safety plan by o Class-Based Safety Plan: A vehicle can make safety plan by
classifying the surrounding vehicles into different groups for classifying the surrounding vehicles into different groups for
safety purposes according to the geometrical relationship among safety purposes according to the geometrical relationship among
them. The vehicle groups can be classified as Line-of-Sight them. The vehicle groups can be classified as Line-of-Sight
Unsafe, Non-Line-of-Sight Unsafe, and Safe groups [CASD]. Unsafe, Non-Line-of-Sight Unsafe, and Safe groups [CASD].
o Context-Awareness: A vehicle can be aware of spatial-temporal o Context-Awareness: A vehicle can be aware of spatial-temporal
mobility information (e.g., position, speed, direction, and mobility information (e.g., position, speed, direction, and
acceleration/deceleration) of surrounding vehicles for both safety acceleration/deceleration) of surrounding vehicles for both safety
and non-safety uses through sensing or communication [CASD]. and non-safety uses through sensing or communication [CASD].
o Edge Computing (EC): It is the local computing near an access
network (i.e., edge network) for the sake of vehicles and
pedestrians.
o Edge Computing Device (ECD): It is a computing device (or server)
for edge computing for the sake of vehicles and pedestrians.
o Edge Network (EN): In is an access network that has an IP-RSU for
wireless communication with other vehicles having an IP-OBU and
wired communication with other network devices (e.g., routers, IP-
RSUs, ECDs, servers, and MA). It may have a radio receiver of
Global Positioning System (GPS) for its position recognition and
the localization service for the sake of vehicles.
o IP-OBU: "Internet Protocol On-Board Unit": An IP-OBU denotes a
computer situated in a vehicle such as a car, bicycle, or similar.
It has at least one IP interface that runs in mode OCB of 802.11
and has an "OBU" transceiver. Also, it may have an IP interface
that runs in Cellular V2X (C-V2X) [TS-23.285-3GPP]. See the
definition of the term "OBU" in [RFC8691].
o IP-RSU: "IP Roadside Unit": An IP-RSU is situated along the road.
It has at least two distinct IP-enabled interfaces. The wireless
PHY/MAC layer of at least one of its IP-enabled interfaces is
configured to operate in 802.11-OCB mode. An IP-RSU communicates
with the IP-OBU over an 802.11 wireless link operating in OCB
mode. Also, it may have an IP interface that runs in C-V2X along
with an "RSU" transceiver. An IP-RSU is similar to an Access
Network Router (ANR), defined in [RFC3753], and a Wireless
Termination Point (WTP), defined in [RFC5415]. See the definition
of the term "RSU" in [RFC8691].
o LiDAR: "Light Detection and Ranging". It is a scanning device to o LiDAR: "Light Detection and Ranging". It is a scanning device to
measure a distance to an object by emitting pulsed laser light and measure a distance to an object by emitting pulsed laser light and
measuring the reflected pulsed light. measuring the reflected pulsed light.
o Mobility Anchor (MA): A node that maintains IP addresses and o Mobility Anchor (MA): A node that maintains IPv6 addresses and
mobility information of vehicles in a road network to support mobility information of vehicles in a road network to support
their address autoconfiguration and mobility management with a their IPv6 address autoconfiguration and mobility management with
binding table. An MA has end-to-end connections with RSUs under a binding table. An MA has End-to-End (E2E) connections with IP-
its control. RSUs under its control for the address autoconfiguration and
mobility management of the vehicles. This MA can play a role of a
Local Mobility Anchor (LMA) in PMIPv6 [RFC5213] for vehicles
moving in the road network .
o On-Board Unit (OBU): A node that has physical communication o OCB: "Outside the Context of a Basic Service Set - BSS". It is a
devices (e.g., IEEE 802.11-OCB and Cellular V2X (C-V2X) mode of operation in which a Station (STA) is not a member of a
[TS-23.285-3GPP]) for wireless communications with other OBUs and BSS and does not utilize IEEE Std 802.11 authentication,
RSUs, and may be connected to in-vehicle devices or networks. An association, or data confidentiality [IEEE-802.11-OCB].
OBU is mounted on a vehicle.
o OCB: "Outside the Context of a Basic Service Set". It is o 802.11-OCB: It refers to the mode specified in IEEE Std
differentiated from the Basic Service Set (BSS) mode in IEEE 802.11-2016 [IEEE-802.11-OCB] when the MIB attribute
802.11 standard. A node in OCB mode can directly transmit packets dot11OCBActivited is 'true'.
to other nodes in its wireless range without the authentication or
association process defined in BSS mode [IEEE-802.11-OCB].
o Platooning: Moving vehicles can be grouped together to reduce air- o Platooning: Moving vehicles can be grouped together to reduce air-
resistance for energy efficiency and reduce the number of drivers resistance for energy efficiency and reduce the number of drivers
such that only the leading vehicle has a driver and the other such that only the leading vehicle has a driver and the other
vehicles are autonomous vehicles without a driver and closely vehicles are autonomous vehicles without a driver and closely
following the leading vehicle [Truck-Platooning]. following the leading vehicle [Truck-Platooning].
o Road-Side Unit (RSU): A node that has physical communication
devices (e.g., IEEE 802.11-OCB and C-V2X) for wireless
communications with vehicles and is also connected to the Internet
through a router or switch for packet forwarding. An RSU can
accommodate multiple routers (or switches) and servers (e.g., DNS
server and edge computing server) in its internal network as an
edge computing system. An RSU is typically deployed on the road
infrastructure, either at an intersection or in a road segment,
but may also be located in a car parking area.
o Traffic Control Center (TCC): A node that maintains road o Traffic Control Center (TCC): A node that maintains road
infrastructure information (e.g., RSUs, traffic signals, and loop infrastructure information (e.g., IP-RSUs, traffic signals, and
detectors), vehicular traffic statistics (e.g., average vehicle loop detectors), vehicular traffic statistics (e.g., average
speed and vehicle inter-arrival time per road segment), and vehicle speed and vehicle inter-arrival time per road segment),
vehicle information (e.g., a vehicle's identifier, position, and vehicle information (e.g., a vehicle's identifier, position,
direction, speed, and trajectory as a navigation path). TCC is direction, speed, and trajectory as a navigation path). TCC is
included in a vehicular cloud for vehicular networks. included in a vehicular cloud for vehicular networks.
o Vehicle: A Vehicle in this document is a node that has an OBU for o Vehicle: A Vehicle in this document is a node that has an IP-OBU
wireless communication with other vehicles and RSUs. It has a for wireless communication with other vehicles and IP-RSUs. It
radio navigation receiver of Global Positioning System (GPS) for has a radio navigation receiver of Global Positioning System (GPS)
efficient navigation. for efficient navigation.
o Vehicular Ad Hoc Network (VANET): A network that consists of o Vehicular Ad Hoc Network (VANET): A network that consists of
vehicles interconnected by wireless communication. Two vehicles vehicles interconnected by wireless communication. Two vehicles
in a VANET can communicate with each other using other vehicles as in a VANET can communicate with each other using other vehicles as
relays even where they are out of one-hop wireless communication relays even where they are out of one-hop wireless communication
range. range.
o Vehicular Cloud: A cloud infrastructure for vehicular networks, o Vehicular Cloud: A cloud infrastructure for vehicular networks,
having compute nodes, storage nodes, and network forwarding having compute nodes, storage nodes, and network forwarding
elements (e.g., switch and router). elements (e.g., switch and router).
o Vehicle Detection Loop (i.e., Loop Detector): An inductive device o Vehicle Detection Loop (i.e., Loop Detector): An inductive device
used for detecting vehicles passing or arriving at a certain used for detecting vehicles passing or arriving at a certain
point, for instance, at an intersection with traffic lights or at point, for instance, at an intersection with traffic lights or at
a ramp toward a highway. The relatively crude nature of the a ramp toward a highway. The relatively crude nature of the
loop's structure means that only metal masses above a certain size loop's structure means that only metal masses above a certain size
are capable of triggering the detection. are capable of triggering the detection.
o V2I2P: "Vehicle to Infrastructure to Pedestrian". o V2D: "Vehicle to Device". It is the wireless communication
between a vehicle and a device (e.g., IoT device).
o V2I2V: "Vehicle to Infrastructure to Vehicle". o V2P: "Vehicle to Pedestrian". It is the wireless communication
between a vehicle and a pedestrian's mobile device (e.g.,
smartphone).
o V2I2P: "Vehicle to Infrastructure to Pedestrian". It is the
wireless communication between a vehicle and a pedestrian's mobile
device (e.g., smartphone) via an infrastructure node (e.g., IP-
RSU).
o V2I2V: "Vehicle to Infrastructure to Vehicle". It is the wireless
communication between a vehicle and another vehicle via an
infrastructure node (e.g., IP-RSU).
o VIP: "Vehicular Internet Protocol". It is an IPv6 extension for
vehicular networks including V2V, V2I, and V2X.
o VMM: "Vehicular Mobility Management". It is an IPv6-based
mobility management for vehicular networks.
o VND: "Vehicular Neighbor Discovery". It is an IPv6 ND extension
for vehicular networks.
o VSP: "Vehicular Security and Privacy". It is an IPv6-based
security and privacy for vehicular networks.
o WAVE: "Wireless Access in Vehicular Environments" [WAVE-1609.0]. o WAVE: "Wireless Access in Vehicular Environments" [WAVE-1609.0].
3. Use Cases 3. Use Cases
This section explains use cases of V2V, V2I, and V2X networking. The This section explains use cases of V2V, V2I, and V2X networking. The
use cases of the V2X networking exclude the ones of the V2V and V2I use cases of the V2X networking exclude the ones of the V2V and V2I
networking, but include Vehicle-to-Pedestrian (V2P) and Vehicle-to- networking, but include Vehicle-to-Pedestrian (V2P) and Vehicle-to-
Device (V2D). Device (V2D).
Since IP is widely used among various computing devices in the
Internet, it is expected that the use cases in this section need to
work on top of IPv6 as the network layer protocol. Thus, the IPv6
for these use cases should be extended for vehicular IPv6 such that
the IPv6 can support the functions of the network layer protocol such
as Vehicular Neighbor Discovery (VND), Vehicular Mobility Management
(VMM), and Vehicular Security and Privacy (VSP) in vehicular
networks. Refer to Section 5 for the problem statement of the
requirements of the vehicular IPv6.
3.1. V2V 3.1. V2V
The use cases of V2V networking discussed in this section include The use cases of V2V networking discussed in this section include
o Context-aware navigation for driving safety and collision o Context-aware navigation for driving safety and collision
avoidance; avoidance;
o Cooperative adaptive cruise control in an urban roadway; o Cooperative adaptive cruise control in an urban roadway;
o Platooning in a highway; o Platooning in a highway;
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pedestrians. [Automotive-Sensing] introduces a millimeter-wave pedestrians. [Automotive-Sensing] introduces a millimeter-wave
vehicular communication for massive automotive sensing. A lot of vehicular communication for massive automotive sensing. A lot of
data can be generated by those sensors, and these data typically need data can be generated by those sensors, and these data typically need
to be routed to different destinations. In addition, from the to be routed to different destinations. In addition, from the
perspective of driverless vehicles, it is expected that driverless perspective of driverless vehicles, it is expected that driverless
vehicles can be mixed with driver-operated vehicles. Through the vehicles can be mixed with driver-operated vehicles. Through the
cooperative environment sensing, driver-operated vehicles can use cooperative environment sensing, driver-operated vehicles can use
environmental information sensed by driverless vehicles for better environmental information sensed by driverless vehicles for better
interaction with the other vehicles and environment. interaction with the other vehicles and environment.
To support the applications of these V2V use cases, the functions of
IPv6 such as VND and VSP are prerequisite for the IPv6-based packet
exchange and the secure, safe communication between two vehicles.
3.2. V2I 3.2. V2I
The use cases of V2I networking discussed in this section include The use cases of V2I networking discussed in this section include
o Navigation service; o Navigation service;
o Energy-efficient speed recommendation service; o Energy-efficient speed recommendation service;
o Accident notification service. o Accident notification service.
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time. The enhanced version of SAINT [SAINTplus] can give fast moving time. The enhanced version of SAINT [SAINTplus] can give fast moving
paths to emergency vehicles (e.g., ambulance and fire engine) to let paths to emergency vehicles (e.g., ambulance and fire engine) to let
them reach an accident spot while redirecting other vehicles near the them reach an accident spot while redirecting other vehicles near the
accident spot into efficient detour paths. accident spot into efficient detour paths.
A TCC can recommend an energy-efficient speed to a vehicle that A TCC can recommend an energy-efficient speed to a vehicle that
depends on its traffic environment. [Fuel-Efficient] studies fuel- depends on its traffic environment. [Fuel-Efficient] studies fuel-
efficient route and speed plans for platooned trucks. efficient route and speed plans for platooned trucks.
The emergency communication between accident vehicles (or emergency The emergency communication between accident vehicles (or emergency
vehicles) and TCC can be performed via either RSU or 4G-LTE networks. vehicles) and TCC can be performed via either IP-RSU or 4G-LTE
The First Responder Network Authority (FirstNet) [FirstNet] is networks. The First Responder Network Authority (FirstNet)
provided by the US government to establish, operate, and maintain an [FirstNet] is provided by the US government to establish, operate,
interoperable public safety broadband network for safety and security and maintain an interoperable public safety broadband network for
network services, e.g., emergency calls. The construction of the safety and security network services, e.g., emergency calls. The
nationwide FirstNet network requires each state in the US to have a construction of the nationwide FirstNet network requires each state
Radio Access Network (RAN) that will connect to the FirstNet's in the US to have a Radio Access Network (RAN) that will connect to
network core. The current RAN is mainly constructed by 4G-LTE for the FirstNet's network core. The current RAN is mainly constructed
the communication between a vehicle and an infrastructure node (i.e., by 4G-LTE for the communication between a vehicle and an
V2I) [FirstNet-Report], but it is expected that DSRC-based vehicular infrastructure node (i.e., V2I) [FirstNet-Report], but it is expected
networks [DSRC] will be available for V2I and V2V in near future. that DSRC-based vehicular networks [DSRC] will be available for V2I
and V2V in near future.
To support the applications of these V2I use cases, the functions of
IPv6 such as VND, VMM, and VSP are prerequisite for the IPv6-based
packet exchange, the transport-layer session continuity, and the
secure, safe communication between a vehicle and a server in the
vehicular cloud.
3.3. V2X 3.3. V2X
The use case of V2X networking discussed in this section is The use case of V2X networking discussed in this section is
pedestrian protection service. pedestrian protection service.
A pedestrian protection service, such as Safety-Aware Navigation A pedestrian protection service, such as Safety-Aware Navigation
Application (SANA) [SANA], using V2I2P networking can reduce the Application (SANA) [SANA], using V2I2P networking can reduce the
collision of a vehicle and a pedestrian carrying a smartphone collision of a vehicle and a pedestrian carrying a smartphone
equipped with a network device for wireless communication (e.g., equipped with a network device for wireless communication (e.g.,
WiFi) with an RSU. Vehicles and pedestrians can also communicate WiFi) with an IP-RSU. Vehicles and pedestrians can also communicate
with each other via an RSU that delivers scheduling information for with each other via an IP-RSU. An edge computing device behind the
wireless communication in order to save the smartphones' battery IP-RSU can collect the mobility information from vehicles and
through sleeping mode. pedestrians, compute wireless communication scheduling for the sake
of them. This scheduling can save the battery of each pedestrian's
smartphone by allowing it to work in sleeping mode before the
communication with vehicles, considering their mobility.
For Vehicle-to-Pedestrian (V2P), a vehicle can directly communicate For Vehicle-to-Pedestrian (V2P), a vehicle can directly communicate
with a pedestrian's smartphone by V2X without RSU relaying. Light- with a pedestrian's smartphone by V2X without IP-RSU relaying.
weight mobile nodes such as bicycles may also communicate directly Light-weight mobile nodes such as bicycles may also communicate
with a vehicle for collision avoidance using V2V. directly with a vehicle for collision avoidance using V2V.
To support the applications of these V2X use cases, the functions of
IPv6 such as VND, VMM, and VSP are prerequisite for the IPv6-based
packet exchange, the transport-layer session continuity, and the
secure, safe communication between a vehicle and a pedestrian either
directly or indirectly via an IP-RSU.
4. Vehicular Networks 4. Vehicular Networks
This section describes a vehicular network architecture supporting This section describes an exemplary vehicular network architecture
V2V, V2I, and V2X communications in vehicular networks. Also, it supporting V2V, V2I, and V2X communications in vehicular networks.
describes an internal network within a vehicle or RSU, and the It describes an internal network within a vehicle or an edge network
internetworking between the internal networks via DSRC links. (called EN). It explains not only the internetworking between the
internal networks of a vehicle and an EN via wireless links, but also
the internetworking between the internal networks of two vehicles via
wireless links.
Traffic Control Center in Vehicular Cloud Traffic Control Center in Vehicular Cloud
******************************************* *******************************************
* * +-------------+ * *
* +-----------------+ * |Corresponding| * +-----------------+ *
* | Mobility Anchor | * | Node |<->* | Mobility Anchor | *
* +-----------------+ * +-------------+ * +-----------------+ *
* ^ * * ^ *
* | Ethernet * * | *
* v * * v *
******************************************* *******************************************
^ ^ ^ ^ ^ ^
| Ethernet | Ethernet | Ethernet | | |
| | | | | |
v v v v v v
+--------+ Ethernet +--------+ Ethernet +--------+ +---------+ +---------+ +---------+
| RSU1 |<-------->| RSU2 |<---------->| RSU3 | | IP-RSU1 |<--------->| IP-RSU2 |<--------->| IP-RSU3 |
+--------+ +--------+ +--------+ +---------+ +---------+ +---------+
^ ^ ^ ^ ^ ^
: : : : : :
+-----------------+ +-----------------+ +-----------------+ +-----------------+ +-----------------+ +-----------------+
| : V2I | | : V2I | | : V2I | | : V2I | | : V2I | | : V2I |
| v | | v | | v | | v | | v | | v |
+--------+ | +--------+ | | +--------+ | | +--------+ | +--------+ | +--------+ | | +--------+ | | +--------+ |
|Vehicle1|===> |Vehicle2|===>| | |Vehicle3|===>| | |Vehicle4|===>| |Vehicle1|===> |Vehicle2|===>| | |Vehicle3|===>| | |Vehicle4|===>|
+--------+<...>+--------+<........>+--------+ | | +--------+ | +--------+<...>+--------+<........>+--------+ | | +--------+ |
V2V ^ V2V ^ | | ^ | V2V ^ V2V ^ | | ^ |
| : V2V | | : V2V | | : V2V | | : V2V | | : V2V | | : V2V |
| v | | v | | v | | v | | v | | v |
| +--------+ | | +--------+ | | +--------+ | | +--------+ | | +--------+ | | +--------+ |
| |Vehicle5|===> | | |Vehicle6|===>| | |Vehicle7|==>| | |Vehicle5|===> | | |Vehicle6|===>| | |Vehicle7|==>|
| +--------+ | | +--------+ | | +--------+ | | +--------+ | | +--------+ | | +--------+ |
+-----------------+ +-----------------+ +-----------------+ +-----------------+ +-----------------+ +-----------------+
Subnet1 Subnet2 Subnet3 Subnet1 Subnet2 Subnet3
(Prefix1) (Prefix2) (Prefix3) (Prefix1) (Prefix2) (Prefix3)
<----> Wired Link <....> Wireless Link ===> Moving Direction <----> Wired Link <....> Wireless Link ===> Moving Direction
Figure 1: A Vehicular Network Architecture for V2I and V2V Networking Figure 1: An Exemplary Vehicular Network Architecture for V2I and V2V
4.1. Vehicular Network Architecture 4.1. Vehicular Network Architecture
Figure 1 shows an architecture for V2I and V2V networking in a road Figure 1 shows an exemplary vehicular network architecture for V2I
network. The vehicular network architecture contains vehicles, RSUs, and V2V in a road network. The vehicular network architecture
Vehicular Cloud, Traffic Control Center, and Mobility Anchor as contains vehicles, IP-RSUs, Vehicular Cloud, Traffic Control Center,
components. However, some components in the vehicular network and Mobility Anchor as components. However, some components in the
architecture may not be needed for vehicular networking, such as vehicular network architecture may not be needed for vehicular
Vehicular Cloud, Traffic Control Center, and Mobility Anchor. networks, such as Vehicular Cloud, Traffic Control Center, and
Mobility Anchor.
As shown in this figure, RSUs as routers and vehicles with OBU have As shown in this figure, IP-RSUs as routers and vehicles with IP-OBU
wireless media interfaces for VANET. Furthermore, the wireless media have wireless media interfaces for VANET. Furthermore, the wireless
interfaces are autoconfigured with a global IPv6 prefix (e.g., media interfaces are autoconfigured with a global IPv6 prefix (e.g.,
2001:DB8:1:1::/64) to support both V2V and V2I networking. Note that 2001:DB8:1:1::/64) to support both V2V and V2I networking. Note that
2001:DB8::/32 is a documentation prefix [RFC3849] for example 2001:DB8::/32 is a documentation prefix [RFC3849] for example
prefixes in this document, and also that any routable IPv6 address prefixes in this document, and also that any routable IPv6 address
needs to be routable in a VANET and a vehicular network including needs to be routable in a VANET and a vehicular network including IP-
RSUs. RSUs.
For IPv6 packets transported over IEEE 802.11-OCB, For IPv6 packets transported over IEEE 802.11-OCB, [RFC8691]
[IPv6-over-802.11-OCB] specifies several details, including Maximum specifies several details, including Maximum Transmission Unit (MTU),
Transmission Unit (MTU), frame format, link-local address, address frame format, link-local address, address mapping for unicast and
mapping for unicast and multicast, stateless autoconfiguration, and multicast, stateless autoconfiguration, and subnet structure. An
subnet structure. An Ethernet Adaptation (EA) layer is in charge of Ethernet Adaptation (EA) layer is in charge of transforming some
transforming some parameters between IEEE 802.11 MAC layer and IPv6 parameters between IEEE 802.11 MAC layer and IPv6 network layer,
network layer, which is located between IEEE 802.11-OCB's logical which is located between IEEE 802.11-OCB's logical link control layer
link control layer and IPv6 network layer. This IPv6 over 802.11-OCB and IPv6 network layer. This IPv6 over 802.11-OCB can be used for
can be used for both V2V and V2I in IP-based vehicular networks. both V2V and V2I in IPv6-based vehicular networks.
In Figure 1, three RSUs (RSU1, RSU2, and RSU3) are deployed in the In Figure 1, three IP-RSUs (IP-RSU1, IP-RSU2, and IP-RSU3) are
road network and are connected to a Vehicular Cloud through the deployed in the road network and are connected with each other
Internet. A Traffic Control Center (TCC) is connected to the through the wired networks (e.g., Ethernet), which are part of a
Vehicular Cloud for the management of RSUs and vehicles in the road Vehicular Cloud. A Traffic Control Center (TCC) is connected to the
network. A Mobility Anchor (MA) can be located in the TCC as its key Vehicular Cloud for the management of IP-RSUs and vehicles in the
component for the mobility management of vehicles. Vehicle2, road network. A Mobility Anchor (MA) may be located in the TCC as a
Vehicle3, and Vehicle4 are wirelessly connected to RSU1, RSU2, and mobility management controller, which is a controller for the
RSU3, respectively. The three wireless networks of RSU1, RSU2, and mobility management of vehicles. Vehicle2, Vehicle3, and Vehicle4
RSU3 can belong to three different subnets (i.e., Subnet1, Subnet2, are wirelessly connected to IP-RSU1, IP-RSU2, and IP-RSU3,
and Subnet3), respectively. Those three subnets use three different respectively. The three wireless networks of IP-RSU1, IP-RSU2, and
prefixes (i.e., Prefix1, Prefix2, and Prefix3). IP-RSU3 can belong to three different subnets (i.e., Subnet1,
Subnet2, and Subnet3), respectively. Those three subnets use three
different prefixes (i.e., Prefix1, Prefix2, and Prefix3).
A single subnet prefix can span multiple vehicles in VANET. For A single subnet prefix can span multiple vehicles in VANET. For
example, in Figure 1, for Prefix 1, three vehicles (i.e., Vehicle1, example, in Figure 1, for Prefix 1, three vehicles (i.e., Vehicle1,
Vehicle2, and Vehicle5) can construct a connected VANET. Also, for Vehicle2, and Vehicle5) can construct a connected VANET. Also, for
Prefix 2, two vehicles (i.e., Vehicle3 and Vehicle6) can construct Prefix 2, two vehicles (i.e., Vehicle3 and Vehicle6) can construct
another connected VANET, and for Prefix 3, two vehicles (i.e., another connected VANET, and for Prefix 3, two vehicles (i.e.,
Vehicle4 and Vehicle7) can construct another connected VANET. Vehicle4 and Vehicle7) can construct another connected VANET.
In wireless subnets in vehicular networks (e.g., Subnet1 and Subnet2 In wireless subnets in vehicular networks (e.g., Subnet1 and Subnet2
in Figure 1), vehicles can construct a connected VANET (with an in Figure 1), vehicles can construct a connected VANET (with an
arbitrary graph topology) and can communicate with each other via V2V arbitrary graph topology) and can communicate with each other via V2V
communication. Vehicle1 can communicate with Vehicle2 via V2V communication. Vehicle1 can communicate with Vehicle2 via V2V
communication, and Vehicle2 can communicate with Vehicle3 via V2V communication, and Vehicle2 can communicate with Vehicle3 via V2V
communication because they are within the wireless communication communication because they are within the wireless communication
range for each other. On the other hand, Vehicle3 can communicate range for each other. On the other hand, Vehicle3 can communicate
with Vehicle4 via the vehicular infrastructure (i.e., RSU2 and RSU3) with Vehicle4 via the vehicular infrastructure (i.e., IP-RSU2 and IP-
by employing V2I (i.e., V2I2V) communication because they are not RSU3) by employing V2I (i.e., V2I2V) communication because they are
within the wireless communication range for each other. not within the wireless communication range for each other.
In vehicular networks, asymmetric links sometimes exist and must be An IPv6 mobility solution is needed in vehicular networks so that a
considered for wireless communications. In vehicular networks, the vehicle's TCP session can be continued while it moves from an IP-
control plane can be separated from the data plane for efficient RSU's wireless coverage to another IP-RSU's wireless coverage. In
mobility management and data forwarding. The mobility information of Figure 1, assuming that Vehicle2 has a TCP session with a
a GPS receiver mounted in its vehicle (e.g., position, speed, and corresponding node in the vehicular cloud, Vehicle2 can move from IP-
direction) can be used to accommodate mobility-aware proactive RSU1's wireless coverage to IP-RSU2's wireless coverage. In this
protocols. Vehicles can use the TCC as their Home Network having a case, a handover for Vehicle2 needs to be performed by either a host-
home agent for mobility management as in MIPv6 [RFC6275] and PMIPv6 based mobility management scheme (e.g., MIPv6 [RFC6275]) or a
[RFC5213], so the TCC maintains the mobility information of vehicles network-based mobility management scheme (e.g., PMIPv6 [RFC5213]).
for location management. IP tunneling over the wireless link should In the host-based mobility scheme, an IP-RSU plays a role of a home
be avoided for performance efficiency. agent in a visited network. On the other hand, in the network-based
mobility scheme, an MA plays a role of a mobility management
controller such as a Local Mobility Anchor (LMA) in PMIPv6, and an
IP-RSU plays a role of an access router such as a Mobile Access
Gateway (MAG) in PMIPv6 [RFC5213].
In vehicular networks, the control plane can be separated from the
data plane for efficient mobility management and data forwarding.
The separation of the control plane and data plane can be performed
by the Software-Defined Networking (SDN) [RFC7149]. An MA can
configure and monitor its IP-RSUs and vehicles for mobility
management, location management, and security services in an
efficient way.
The mobility information of a GPS receiver mounted in its vehicle
(e.g., position, speed, and direction) can be used to accommodate
mobility-aware proactive handover schemes, which can perform the
handover of a vehicle according to its mobility and the wireless
signal strength of a vehicle and an IP-RSU in a proactive way.
Vehicles can use the TCC as their Home Network having a home agent
for mobility management as in MIPv6 [RFC6275] and PMIPv6 [RFC5213],
so the TCC maintains the mobility information of vehicles for
location management. IP tunneling over the wireless link should be
avoided for performance efficiency. Also, in vehicular networks,
asymmetric links sometimes exist and must be considered for wireless
communications such as V2V and V2I.
+-----------------+ +-----------------+
(*)<........>(*) +----->| Vehicular Cloud | (*)<........>(*) +----->| Vehicular Cloud |
2001:DB8:1:1::/64 | | | +-----------------+ 2001:DB8:1:1::/64 | | | +-----------------+
+------------------------------+ +---------------------------------+ +------------------------------+ +---------------------------------+
| v | | v v | | v | | v v |
| +-------+ +------+ +-------+ | | +-------+ +------+ +-------+ | | +-------+ +-------+ | | +-------+ +-------+ |
| | Host1 | | DNS1 | |Router1| | | |Router3| | DNS2 | | Host3 | | | | Host1 | |IP-OBU1| | | |IP-RSU1| | Host3 | |
| +-------+ +------+ +-------+ | | +-------+ +------+ +-------+ | | +-------+ +-------+ | | +-------+ +-------+ |
| ^ ^ ^ | | ^ ^ ^ | | ^ ^ | | ^ ^ |
| | | | | | | | | | | | | | | | | |
| v v v | | v v v | | v v | | v v |
| ---------------------------- | | ------------------------------- | | ---------------------------- | | ------------------------------- |
| 2001:DB8:10:1::/64 ^ | | ^ 2001:DB8:20:1::/64 | | 2001:DB8:10:1::/64 ^ | | ^ 2001:DB8:20:1::/64 |
| | | | | | | | | | | |
| v | | v | | v | | v |
| +-------+ +-------+ | | +-------+ +-------+ +-------+ | | +-------+ +-------+ | | +-------+ +-------+ +-------+ |
| | Host2 | |Router2| | | |Router4| |Server1|...|ServerN| | | | Host2 | |Router1| | | |Router2| |Server1|...|ServerN| |
| +-------+ +-------+ | | +-------+ +-------+ +-------+ | | +-------+ +-------+ | | +-------+ +-------+ +-------+ |
| ^ ^ | | ^ ^ ^ | | ^ ^ | | ^ ^ ^ |
| | | | | | | | | | | | | | | | | |
| v v | | v v v | | v v | | v v v |
| ---------------------------- | | ------------------------------- | | ---------------------------- | | ------------------------------- |
| 2001:DB8:10:2::/64 | | 2001:DB8:20:2::/64 | | 2001:DB8:10:2::/64 | | 2001:DB8:20:2::/64 |
+------------------------------+ +---------------------------------+ +------------------------------+ +---------------------------------+
Vehicle1 (Moving Network1) RSU1 (Fixed Network1) Vehicle1 (Moving Network1) EN1 (Fixed Network1)
<----> Wired Link <....> Wireless Link (*) Antenna <----> Wired Link <....> Wireless Link (*) Antenna
Figure 2: Internetworking between Vehicle Network and RSU Network Figure 2: Internetworking between Vehicle and Edge Network
4.2. V2I-based Internetworking 4.2. V2I-based Internetworking
This section discusses the internetworking between a vehicle's This section discusses the internetworking between a vehicle's
internal network (i.e., moving network) and an RSU's internal network internal network (i.e., moving network) and an EN's internal network
(i.e., fixed network) via V2I communication. Note that an RSU can (i.e., fixed network) via V2I communication. Note that an EN can
accommodate multiple routers (or switches) and servers (e.g., DNS accommodate multiple routers (or switches) and servers (e.g., ECDs,
server and edge computing server) in its internal network as an edge navigation server, and DNS server) in its internal network.
computing system.
A vehicle's internal network often uses Ethernet to interconnect A vehicle's internal network often uses Ethernet to interconnect
control units in the vehicle. The internal network also supports Electronic Control Units (ECUs) in the vehicle. The internal network
WiFi and Bluetooth to accommodate a driver's and passenger's mobile can support WiFi and Bluetooth to accommodate a driver's and
devices (e.g., smartphone or tablet). It is reasonable to consider passenger's mobile devices (e.g., smartphone or tablet). The network
the interaction between the internal network and an external network topology and subnetting depend on each vendor's network configuration
within another vehicle or RSU. for a vehicle and an EN. It is reasonable to consider the
interaction between the internal network and an external network
As shown in Figure 2, the vehicle's moving network and the RSU's within another vehicle or an EN.
fixed network are self-contained networks having multiple subnets and
having an edge router for the communication with another vehicle or
RSU. Internetworking between two internal networks via V2I
communication requires an exchange of network prefix and other
parameters through a prefix discovery mechanism, such as ND-based
prefix discovery [ID-Vehicular-ND]. For ND-based prefix discovery,
network prefixes and parameters should be registered with a vehicle's
router and an RSU router with an external network interface in
advance.
For an IP communication between a vehicle and an RSU or between two
neighboring vehicles, the network parameter discovery collects
information relevant to the link layer, MAC layer, and IP layer. The
link layer information includes wireless link layer parameters and
transmission power level. The MAC layer information includes the MAC
address of an external network interface for the internetworking with
another vehicle or RSU. The IP layer information includes the IP
address and prefix of an external network interface for the
internetworking with another vehicle or RSU.
Once the network parameter discovery and prefix exchange operations As shown in Figure 2, as internal networks, a vehicle's moving
have been performed, packets can be transmitted between the vehicle's network and an EN's fixed network are self-contained networks having
moving network and the RSU's fixed network. A DNS service should be multiple subnets and having an edge router (e.g., IP-OBU and IP-RSU)
supported for the DNS name resolution of in-vehicle devices within a for the communication with another vehicle or another EN.
vehicle's internal network as well as for the DNS name resolution of Internetworking between two internal networks via V2I communication
those devices from a remote host in the Internet (e.g., a customer's requires the exchange of the network parameters and the network
web browser and an automotive service center system). The DNS names prefixes of the internal networks.
of in-vehicle devices and their service names can be registered with
a DNS server in a vehicle or an RSU, as shown in Figure 2.
Figure 2 also shows internetworking between the vehicle's moving Figure 2 also shows internetworking between the vehicle's moving
network and the RSU's fixed network. There exists an internal network and the EN's fixed network. There exists an internal network
network (Moving Network1) inside Vehicle1. Vehicle1 has the DNS (Moving Network1) inside Vehicle1. Vehicle1 has two hosts (Host1 and
Server (DNS1), the two hosts (Host1 and Host2), and the two routers Host2), and two routers (IP-OBU1 and Router1). There exists another
(Router1 and Router2). There exists another internal network (Fixed internal network (Fixed Network1) inside EN1. EN1 has one host
Network1) inside RSU1. RSU1 has the DNS Server (DNS2), one host (Host3), two routers (IP-RSU1 and Router2), and the collection of
(Host3), the two routers (Router3 and Router4), and the collection of
servers (Server1 to ServerN) for various services in the road servers (Server1 to ServerN) for various services in the road
networks, such as the emergency notification and navigation. networks, such as the emergency notification and navigation.
Vehicle1's Router1 (a mobile router) and RSU1's Router3 (a fixed Vehicle1's IP-OBU1 (as a mobile router) and EN1's IP-RSU1 (as a fixed
router) use 2001:DB8:1:1::/64 for an external link (e.g., DSRC) for router) use 2001:DB8:1:1::/64 for an external link (e.g., DSRC) for
V2I networking. Thus, one host (Host1) in Vehicle1 can communicate V2I networking. Thus, a host (Host1) in Vehicle1 can communicate
with one server (Server1) in RSU1 for a vehicular service through with a server (Server1) in EN1 for a vehicular service through
Vehicle1's moving network, a wireless link between Vehicle1 and RSU1, Vehicle1's moving network, a wireless link between IP-OBU1 and IP-
and RSU1's fixed network. RSU1, and EN1's fixed network.
For an IPv6 communication between an IP-OBU and an IP-RSU or between
two neighboring IP-OBUs, network parameters need to be shared among
them, such as MAC layer and IPv6 layer information. The MAC layer
information includes wireless link layer parameters, transmission
power level, the MAC address of an external network interface for the
internetworking with another IP-OBU or IP-RSU. The IPv6 layer
information includes the IPv6 address and network prefix of an
external network interface for the internetworking with another IP-
OBU or IP-RSU.
Through the exchange of network parameters and network prefixes among
internal networks, packets can be transmitted between the vehicle's
moving network and the EN's fixed network. Thus, V2I requires an
efficient exchange protocol for network parameters and an efficient
routing protocol for network prefixes.
(*)<..........>(*) (*)<..........>(*)
2001:DB8:1:1::/64 | | 2001:DB8:1:1::/64 | |
+------------------------------+ +------------------------------+ +------------------------------+ +------------------------------+
| v | | v | | v | | v |
| +-------+ +------+ +-------+ | | +-------+ +------+ +-------+ | | +-------+ +-------+ | | +-------+ +-------+ |
| | Host1 | | DNS1 | |Router1| | | |Router5| | DNS3 | | Host4 | | | | Host1 | |IP-OBU1| | | |IP-OBU2| | Host3 | |
| +-------+ +------+ +-------+ | | +-------+ +------+ +-------+ | | +-------+ +-------+ | | +-------+ +-------+ |
| ^ ^ ^ | | ^ ^ ^ | | ^ ^ | | ^ ^ |
| | | | | | | | | | | | | | | | | |
| v v v | | v v v | | v v | | v v |
| ---------------------------- | | ---------------------------- | | ---------------------------- | | ---------------------------- |
| 2001:DB8:10:1::/64 ^ | | ^ 2001:DB8:30:1::/64 | | 2001:DB8:10:1::/64 ^ | | ^ 2001:DB8:30:1::/64 |
| | | | | | | | | | | |
| v | | v | | v | | v |
| +-------+ +-------+ | | +-------+ +-------+ | | +-------+ +-------+ | | +-------+ +-------+ |
| | Host2 | |Router2| | | |Router6| | Host5 | | | | Host2 | |Router1| | | |Router2| | Host4 | |
| +-------+ +-------+ | | +-------+ +-------+ | | +-------+ +-------+ | | +-------+ +-------+ |
| ^ ^ | | ^ ^ | | ^ ^ | | ^ ^ |
| | | | | | | | | | | | | | | |
| v v | | v v | | v v | | v v |
| ---------------------------- | | ---------------------------- | | ---------------------------- | | ---------------------------- |
| 2001:DB8:10:2::/64 | | 2001:DB8:30:2::/64 | | 2001:DB8:10:2::/64 | | 2001:DB8:30:2::/64 |
+------------------------------+ +------------------------------+ +------------------------------+ +------------------------------+
Vehicle1 (Moving Network1) Vehicle2 (Moving Network2) Vehicle1 (Moving Network1) Vehicle2 (Moving Network2)
<----> Wired Link <....> Wireless Link (*) Antenna <----> Wired Link <....> Wireless Link (*) Antenna
Figure 3: Internetworking between Two Vehicle Networks Figure 3: Internetworking between Two Vehicles
4.3. V2V-based Internetworking 4.3. V2V-based Internetworking
This section discusses the internetworking between the moving This section discusses the internetworking between the moving
networks of two neighboring vehicles via V2V communication. networks of two neighboring vehicles via V2V communication.
Figure 3 shows internetworking between the moving networks of two Figure 3 shows internetworking between the moving networks of two
neighboring vehicles. There exists an internal network (Moving neighboring vehicles. There exists an internal network (Moving
Network1) inside Vehicle1. Vehicle1 has the DNS Server (DNS1), the Network1) inside Vehicle1. Vehicle1 has two hosts (Host1 and Host2),
two hosts (Host1 and Host2), and the two routers (Router1 and and two routers (IP-OBU1 and Router1). There exists another internal
Router2). There exists another internal network (Moving Network2) network (Moving Network2) inside Vehicle2. Vehicle2 has two hosts
inside Vehicle2. Vehicle2 has the DNS Server (DNS3), the two hosts (Host3 and Host4), and two routers (IP-OBU2 and Router2). Vehicle1's
(Host4 and Host5), and the two routers (Router5 and Router6). IP-OBU1 (as a mobile router) and Vehicle2's IP-OBU2 (as a mobile
Vehicle1's Router1 (a mobile router) and Vehicle2's Router5 (a mobile
router) use 2001:DB8:1:1::/64 for an external link (e.g., DSRC) for router) use 2001:DB8:1:1::/64 for an external link (e.g., DSRC) for
V2V networking. Thus, one host (Host1) in Vehicle1 can communicate V2V networking. Thus, a host (Host1) in Vehicle1 can communicate
with one host (Host4) in Vehicle1 for a vehicular service through with another host (Host3) in Vehicle2 for a vehicular service through
Vehicle1's moving network, a wireless link between Vehicle1 and Vehicle1's moving network, a wireless link between IP-OBU1 and IP-
Vehicle2, and Vehicle2's moving network. OBU2, and Vehicle2's moving network.
(*)<..................>(*)<..................>(*) (*)<..................>(*)<..................>(*)
| | | | | |
+-----------+ +-----------+ +-----------+ +-----------+ +-----------+ +-----------+
| | | | | | | | | | | |
| +-------+ | | +-------+ | | +-------+ | | +-------+ | | +-------+ | | +-------+ |
| |Router1| | | |Router5| | | |Router7| | | |IP-OBU1| | | |IP-OBU2| | | |IP-OBU3| |
| +-------+ | | +-------+ | | +-------+ | | +-------+ | | +-------+ | | +-------+ |
| | | | | | | | | | | |
| +-------+ | | +-------+ | | +-------+ | | +-------+ | | +-------+ | | +-------+ |
| | Host1 | | | | Host4 | | | | Host6 | | | | Host1 | | | | Host2 | | | | Host3 | |
| +-------+ | | +-------+ | | +-------+ | | +-------+ | | +-------+ | | +-------+ |
| | | | | | | | | | | |
+-----------+ +-----------+ +-----------+ +-----------+ +-----------+ +-----------+
Vehicle1 Vehicle2 Vehicle3 Vehicle1 Vehicle2 Vehicle3
<....> Wireless Link (*) Antenna <....> Wireless Link (*) Antenna
Figure 4: Multihop Internetworking between Two Vehicle Networks Figure 4: Multihop Internetworking between Two Vehicle Networks
Figure 4 shows multihop internetworking between the moving networks Figure 4 shows multihop internetworking between the moving networks
of two vehicles in the same VANET. For example, Host1 in Vehicle1 of two vehicles in the same VANET. For example, Host1 in Vehicle1
can communicate with Host6 in Vehicle3 via Router 5 in Vehicle2 that can communicate with Host3 in Vehicle3 via IP-OBU1 in Vehicle1, IP-
is an intermediate vehicle being connected to Vehicle1 and Vehicle3 OBU2 in Vehicle2, and IP-OBU3 in Vehicle3 in a linear topology as
in a linear topology as shown in the figure. shown in the figure.
5. Problem Statement 5. Problem Statement
In order to specify protocols using the abovementioned architecture In order to specify protocols using the abovementioned architecture
for VANETs, IPv6 core protocols have to be adapted to overcome for VANETs, IPv6 core protocols have to be adapted to overcome
certain challenging aspects of vehicular networking. Since the certain challenging aspects of vehicular networking. Since the
vehicles are likely to be moving at great speed, protocol exchanges vehicles are likely to be moving at great speed, protocol exchanges
need to be completed in a time relatively small compared to the need to be completed in a time relatively small compared to the
lifetime of a link between a vehicle and an RSU, or between two lifetime of a link between a vehicle and an IP-RSU, or between two
vehicles. This has a major impact on IPv6 neighbor discovery. vehicles. This has a major impact on IPv6 Neighbor Discovery (ND).
Mobility management is also vulnerable to disconnections that occur Mobility Management (MM) is also vulnerable to disconnections that
before the completion of identity verification and tunnel management. occur before the completion of identity verification and tunnel
This is especially true given the unreliable nature of wireless management. This is especially true given the unreliable nature of
communications. Finally, and perhaps most importantly, proper wireless communications. Thus, this section presents key topics such
authorization for vehicular protocol messages must be assured in as neighbor discovery and mobility management.
order to prevent false reports of accidents or other mishaps on the
road, which would cause horrific misery in modern urban environments.
This section presents key topics such as neighbor discovery and
mobility management.
5.1. Neighbor Discovery 5.1. Neighbor Discovery
IPv6 Neighbor Discovery (IPv6 ND) [RFC4861][RFC4862] is a core part IPv6 ND [RFC4861][RFC4862] is a core part of the IPv6 protocol suite.
of the IPv6 protocol suite. IPv6 ND is designed for point-to-point IPv6 ND is designed for point-to-point links and transit links (e.g.,
links and transit links (e.g., Ethernet). It assumes an efficient Ethernet). It assumes an efficient and reliable support of multicast
and reliable support of multicast from the link layer for various from the link layer for various network operations such as MAC
network operations such as MAC Address Resolution (AR) and Duplicate Address Resolution (AR) and Duplicate Address Detection (DAD).
Address Detection (DAD).
DAD and ND-related parameters (e.g., Router Lifetime) need to be Vehicles move quickly within the communication coverage of any
extended to vehicular networking (e.g., V2V, V2I, and V2X). Vehicles particular vehicle or IP-RSU. Before the vehicles can exchange
move quickly within the communication coverage of any particular application messages with each other, they need to be configured with
vehicle or RSU. Before the vehicles can exchange application a link-local IPv6 address or a global IPv6 address, and run IPv6 ND.
messages with each other, they need to be configured with a link-
local IPv6 address or a global IPv6 address, and run IPv6 ND.
The legacy DAD assumes that a node with an IPv6 address can reach any The legacy DAD assumes that a node with an IPv6 address can reach any
other node with the scope of its address at the time it claims its other node with the scope of its address at the time it claims its
address, and can hear any future claim for that address by another address, and can hear any future claim for that address by another
party within the scope of its address for the duration of the address party within the scope of its address for the duration of the address
ownership. However, the partitioning and merging of VANETs makes ownership. However, the partitioning and merging of VANETs makes
this assumption frequently invalid in vehicular networks. The this assumption frequently invalid in vehicular networks. The
merging and partitioning of VANETs occurs frequently in vehicular merging and partitioning of VANETs occurs frequently in vehicular
networks. This merging and partitioning should be considered for the networks. This merging and partitioning should be considered for the
IPv6 Neighbor Discovery (e.g., SLAAC). Due to the merging of VANETs, IPv6 ND such as IPv6 Stateless Address Autoconfiguration (SLAAC)
two IPv6 addresses may conflict with each other though they were [RFC4862]. Due to the merging of VANETs, two IPv6 addresses may
unique before the merging. Also, the partitioning of a VANET may conflict with each other though they were unique before the merging.
make vehicles with the same prefix be physically unreachable. Also, Also, the partitioning of a VANET may make vehicles with the same
SLAAC should be extended to prevent IPv6 address duplication due to prefix be physically unreachable. Also, SLAAC needs to prevent IPv6
the merging of VANETs. According to the merging and partitioning, a address duplication due to the merging of VANETs. According to the
destination vehicle (as an IP host) should be distinguished as either merging and partitioning, a destination vehicle (as an IPv6 host)
an on-link host or off-link host even though the source vehicle uses needs to be distinguished as either an on-link host or an off-link
the same prefix with the destination vehicle. host even though the source vehicle uses the same prefix with the
destination vehicle.
The vehicular networks need to support a vehicular-network-wide DAD To efficiently prevent the IPv6 address duplication due to the VANET
by defining a scope that is compatible with the legacy DAD, and two partitioning and merging from happing in vehicular networks, the
vehicles can communicate with each other when there exists a vehicular networks need to support a vehicular-network-wide DAD by
communication path over VANET or a combination of VANETs and RSUs, as defining a scope that is compatible with the legacy DAD. In this
shown in Figure 1. By using the vehicular-network-wide DAD, vehicles case, two vehicles can communicate with each other when there exists
can assure that their IPv6 addresses are unique in the vehicular a communication path over VANET or a combination of VANETs and IP-
network whenever they are connected to the vehicular infrastructure RSUs, as shown in Figure 1. By using the vehicular-network-wide DAD,
or become disconnected from it in the form of VANET. A vehicular vehicles can assure that their IPv6 addresses are unique in the
infrastructure having RSUs and an MA can participate in the vehicular network whenever they are connected to the vehicular
vehicular-network-wide DAD for the sake of vehicles [RFC6775]. For infrastructure or become disconnected from it in the form of VANET.
the vehicle as an IPv6 node, deriving a unique IPv6 address from a
globally unique MAC address creates a privacy issue. Refer to
Section 6 for the discussion about such a privacy issue.
ND time-related parameters such as router lifetime and Neighbor ND time-related parameters such as router lifetime and Neighbor
Advertisement (NA) interval should be adjusted for high-speed Advertisement (NA) interval need to be adjusted for high-speed
vehicles and vehicle density. As vehicles move faster, the NA vehicles and vehicle density. As vehicles move faster, the NA
interval should decrease (e.g., from 1 sec to 0.5 sec) for the NA interval should decrease (e.g., from 1 sec to 0.5 sec) for the NA
messages to reach the neighboring vehicles promptly. Also, as messages to reach the neighboring vehicles promptly. Also, as
vehicle density is higher, the NA interval should increase (e.g., vehicle density is higher, the NA interval should increase (e.g.,
from 0.5 sec to 1 sec) for the NA messages to reduce collision from 0.5 sec to 1 sec) for the NA messages to reduce collision
probability with other NA messages. probability with other NA messages.
According to a report from the National Highway Traffic Safety For IPv6-based safety applications (e.g., context-aware navigation,
Administration (NHTSA) [NHTSA-ACAS-Report], an extra 0.5 second of adaptive cruise control, and platooning) in vehicular networks, the
warning time can prevent about 60% of the collisions of vehicles delay-bounded data delivery is critical. Implementations for such
moving closely in a roadway. A warning message should be exchanged applications are not available yet. IPv6 ND needs to efficiently
every 0.5 second. Thus, if the ND messages (e.g., NS and NA) are work to support IPv6-based safety applications.
used as warning messages, they should be exchanged every 0.5 second.
For IP-based safety applications (e.g., context-aware navigation,
adaptive cruise control, and platooning) in vehicular network, this
bounded data delivery is critical. Implementations for such
applications are not available yet. ND needs work to support IP-
based safety applications.
5.1.1. Link Model 5.1.1. Link Model
A prefix model for a vehicular network needs to facilitate the
communication between two vehicles with the same prefix regardless of
the vehicular network topology as long as there exist bidirectional
E2E paths between them in the vehicular network including VANETs and
IP-RSUs. This prefix model allows vehicles with the same prefix to
communicate with each other via a combination of multihop V2V and
multihop V2I with VANETs and IP-RSUs.
IPv6 protocols work under certain assumptions for the link model that IPv6 protocols work under certain assumptions for the link model that
do not necessarily hold in a vehicular wireless link [VIP-WAVE] do not necessarily hold in a vehicular wireless link
[RFC5889]. For instance, some IPv6 protocols assume symmetry in the [VIP-WAVE][RFC5889]. For instance, some IPv6 protocols assume
connectivity among neighboring interfaces [RFC6250]. However, symmetry in the connectivity among neighboring interfaces [RFC6250].
interference and different levels of transmission power may cause However, radio interference and different levels of transmission
asymmetric links to appear in vehicular wireless links. As a result, power may cause asymmetric links to appear in vehicular wireless
a new vehicular link model should consider the asymmetry of links. As a result, a new vehicular link model needs to consider the
dynamically changing vehicular wireless links. asymmetry of dynamically changing vehicular wireless links.
There is a relationship between a link and a prefix, besides the There is a relationship between a link and a prefix, besides the
different scopes that are expected from the link-local and global different scopes that are expected from the link-local and global
types of IPv6 addresses. In an IPv6 link, it is assumed that all types of IPv6 addresses. In an IPv6 link, it is assumed that all
interfaces which are configured with the same subnet prefix and with interfaces which are configured with the same subnet prefix and with
on-link bit set can communicate with each other on an IP link. on-link bit set can communicate with each other on an IPv6 link.
However, the vehicular link model needs to define the relationship However, the vehicular link model needs to define the relationship
between a link and a prefix, considering the dynamics of wireless between a link and a prefix, considering the dynamics of wireless
links and the characteristics of VANET. links and the characteristics of VANET.
A VANET can have multiple links between pairs of vehicles within A VANET can have multiple links between pairs of vehicles within
wireless communication range, as shown in Figure 4. When two wireless communication range, as shown in Figure 4. When two
vehicles belong to the same VANET, but they are out of wireless vehicles belong to the same VANET, but they are out of wireless
communication range, they cannot communicate directly with each communication range, they cannot communicate directly with each
other. Suppose that a global-scope IPv6 prefix is assigned to VANETs other. Suppose that a global-scope IPv6 prefix is assigned to VANETs
in vehicular networks. Even though two vehicles in the same VANET in vehicular networks. Even though two vehicles in the same VANET
configure their IPv6 addresses with the same IPv6 prefix, they may configure their IPv6 addresses with the same IPv6 prefix, they may
not communicate with each other not in a one hop in the same VANET not communicate with each other not in a one hop in the same VANET
because of the multihop network connectivity. Thus, in this case, because of the multihop network connectivity between them. Thus, in
the concept of an on-link IPv6 prefix does not hold because two this case, the concept of an on-link IPv6 prefix does not hold
vehicles with the same on-link IPv6 prefix cannot communicate because two vehicles with the same on-link IPv6 prefix cannot
directly with each other. Also, when two vehicles are located in two communicate directly with each other. Also, when two vehicles are
different VANETs with the same IPv6 prefix, they cannot communicate located in two different VANETs with the same IPv6 prefix, they
with each other. When these two VANETs converge to one VANET, the cannot communicate with each other. When these two VANETs converge
two vehicles can communicate with each other in a multihop fashion. to one VANET, the two vehicles can communicate with each other in a
multihop fashion, for example, wheh they are Vehicle1 and Vehicle3,
as shown in Figure 4.
From the previous observation, a vehicular link model should consider From the previous observation, a vehicular link model should consider
the frequent partitioning and merging of VANETs due to vehicle the frequent partitioning and merging of VANETs due to vehicle
mobility. Therefore, the vehicular link model needs to use an on- mobility. Therefore, the vehicular link model needs to use an on-
link prefix and off-link prefix according to the one-hop reachability link prefix and off-link prefix according to the network topology of
among the vehicles in an appropriate way. If the vehicles with the vehicles such as a one-hop reachable network and a multihop reachable
same prefix are reachable with each other in one hop, the prefix network (or partitioned networks). If the vehicles with the same
should be on-link. On the other hand, if some of the vehicles with prefix are reachable with each other in one hop, the prefix should be
the same prefix are not reachable with each other in one hop due to on-link. On the other hand, if some of the vehicles with the same
either the multi-hop topology in the VANET or multiple partitions, prefix are not reachable with each other in one hop due to either the
the prefix should be off-link. multihop topology in the VANET or multiple partitions, the prefix
should be off-link.
The vehicular link model needs to support the multihop routing in a The vehicular link model needs to support the multihop routing in a
connected VANET where the vehicles with the same global-scope IPv6 connected VANET where the vehicles with the same global-scope IPv6
prefix are connected in one hop or multiple hops. It also needs to prefix are connected in one hop or multiple hops. It also needs to
support the multihop routing in multiple connected VANETs via an RSU support the multihop routing in multiple connected VANETs through
that has the wireless connectivity with each VANET. For example, in infrastructure nodes (e.g., IP-RSU) where they are connected to the
Figure 1, suppose that Vehicle1, Vehicle2, and Vehicle3 are infrastructure. For example, in Figure 1, suppose that Vehicle1,
configured with their IPv6 addresses based on the same global-scope Vehicle2, and Vehicle3 are configured with their IPv6 addresses based
IPv6 prefix. Vehicle1 and Vehicle3 can also communicate with each on the same global-scope IPv6 prefix. Vehicle1 and Vehicle3 can also
other via either multi-hop V2V or multi-hop V2I2V. When two vehicles communicate with each other via either multihop V2V or multihop
of Vehicle1 and Vehicle3 are connected in a VANET, it will be more V2I2V. When the two vehicles of Vehicle1 and Vehicle3 are connected
efficient for them to communicate with each other via VANET rather in a VANET, it will be more efficient for them to directly
than RSUs. On the other hand, when the two vehicles of Vehicle1 and communicate with each other via VANET rather than indirectly via IP-
RSUs. On the other hand, when the two vehicles of Vehicle1 and
Vehicle3 are far away from the communication range in separate VANETs Vehicle3 are far away from the communication range in separate VANETs
and under two different RSUs, they can communicate with each other and under two different IP-RSUs, they can communicate with each other
through the relay of RSUs via V2I2V. Thus, two separate VANETs can through the relay of IP-RSUs via V2I2V. Thus, two separate VANETs
merge into one network via RSU(s). Also, newly arriving vehicles can can merge into one network via IP-RSU(s). Also, newly arriving
merge two separate VANETs into one VANET if they can play a role of a vehicles can merge two separate VANETs into one VANET if they can
relay node for those VANETs. play a role of a relay node for those VANETs.
5.1.2. MAC Address Pseudonym 5.1.2. MAC Address Pseudonym
For the protection of drivers' privacy, a pseudonym of a MAC address For the protection of drivers' privacy, a pseudonym of a MAC address
of a vehicle's network interface should be used, so that the MAC of a vehicle's network interface should be used, so that the MAC
address can be changed periodically. However, although such a address can be changed periodically. However, although such a
pseudonym of a MAC address can protect some extent of privacy of a pseudonym of a MAC address can protect some extent of privacy of a
vehicle, it may not be able to resist attacks on vehicle vehicle, it may not be able to resist attacks on vehicle
identification by other fingerprint information, for example, the identification by other fingerprint information, for example, the
scrambler seed embedded in IEEE 802.11-OCB frames [Scrambler-Attack]. scrambler seed embedded in IEEE 802.11-OCB frames [Scrambler-Attack].
The pseudonym of a MAC address affects an IPv6 address based on the The pseudonym of a MAC address affects an IPv6 address based on the
MAC address, and a transport-layer (e.g., TCP) session with an IPv6 MAC address, and a transport-layer (e.g., TCP and and SCTP) session
address pair. However, the pseudonym handling is not implemented and with an IPv6 address pair. However, the pseudonym handling is not
tested yet for applications on IP-based vehicular networking. implemented and tested yet for applications on IP-based vehicular
networking.
In the ETSI standards, for the sake of security and privacy, an ITS In the ETSI standards, for the sake of security and privacy, an ITS
station (e.g., vehicle) can use pseudonyms for its network interface station (e.g., vehicle) can use pseudonyms for its network interface
identities (e.g., MAC address) and the corresponding IPv6 addresses identities (e.g., MAC address) and the corresponding IPv6 addresses
[Identity-Management]. Whenever the network interface identifier [Identity-Management]. Whenever the network interface identifier
changes, the IPv6 address based on the network interface identifier changes, the IPv6 address based on the network interface identifier
should be updated, and the uniqueness of the address should be needs to be updated, and the uniqueness of the address needs to be
performed through the DAD procedure. For vehicular networks with checked through the DAD procedure. For vehicular networks with high
high mobility and density, this DAD should be performed efficiently mobility and density, this DAD needs to be performed efficiently with
with minimum overhead so that the vehicles can exchange warning minimum overhead so that the vehicles can exchange application
messages with each other every 0.5 second [NHTSA-ACAS-Report]. messages (e.g., collision avoidance and accident notification) with
each other with a short interval (e.g., 0.5 second)
For the continuity of an end-to-end (E2E) transport-layer (e.g., TCP, [NHTSA-ACAS-Report].
UDP, and SCTP) session, with a mobility management scheme (e.g.,
MIPv6 and PMIPv6), the new IP address for the transport-layer session
can be notified to an appropriate end point, and the packets of the
session should be forwarded to their destinations with the changed
network interface identifier and IPv6 address. This mobility
management overhead for pseudonyms should be minimized for efficient
operations in vehicular networks having lots of vehicles.
5.1.3. Routing 5.1.3. Routing
For multihop V2V communications in either a VANET or VANETs via RSUs, For multihop V2V communications in either a VANET or VANETs via IP-
a vehicular ad hoc routing protocol (e.g., AODV and OLSRv2) may be RSUs, a vehicular ad hoc routing protocol (e.g., AODV and OLSRv2) may
required to support both unicast and multicast in the links of the be required to support both unicast and multicast in the links of the
subnet with the same IPv6 prefix. However, it will be costly to run subnet with the same IPv6 prefix. However, it will be costly to run
both vehicular ND and a vehicular ad hoc routing protocol in terms of both vehicular ND and a vehicular ad hoc routing protocol in terms of
control traffic overhead [ID-Multicast-Problems]. control traffic overhead [ID-Multicast-Problems].
The merging of the IPv6 Neighbor Discovery and a VANET routing A routing protocol for VANET may cause redundant wireless frames in
protocol allows the efficient wireless channel utilization. A the air to check the neighborhood of each vehicle and compute the
routing protocol for VANET may cause redundant wireless frames in the routing information in VANET with a dynamic network topology because
air to check the neighborhood of each vehicle and compute the routing the IPv6 ND is used to check the neighborhood of each vehicle. Thus,
information in VANET with a dynamic network topology if the IPv6 ND the vehicular routing needs to take advantage of the IPv6 ND to
is used to check the neighborhood of each vehicle, and can be minimize its control overhead.
extended to compute each vehicle's routing table in VANET.
Vehicular ND can be extended to accommodate routing functionality
with a prefix discovery option. The ND extension can allow vehicles
to exchange their prefixes in a multihop fashion [ID-Vehicular-ND].
With the exchanged prefixes, they can compute their routing table (or
IPv6 ND's neighbor cache) for the VANETs with a distance-vector
algorithm [Intro-to-Algorithms].
5.2. Mobility Management 5.2. Mobility Management
The seamless connectivity and timely data exchange between two end The seamless connectivity and timely data exchange between two end
points requires an efficient mobility management including location points requires an efficient mobility management including location
management and handover. Most of vehicles are equipped with a GPS management and handover. Most of vehicles are equipped with a GPS
receiver as part of a dedicated navigation system or a corresponding receiver as part of a dedicated navigation system or a corresponding
smartphone App. The GPS receiver may not provide vehicles with smartphone App. Note that The GPS receiver may not provide vehicles
accurate location information in adverse, local environments such as with accurate location information in adverse environments such as a
building area and tunnel. The location precision can be improved by building area and tunnel. The location precision can be improved by
the assistance from the RSUs or a cellular system with a GPS receiver the assistance from the IP-RSUs or a cellular system with a GPS
for location information. receiver for location information.
With a GPS navigator, an efficient mobility management will be With a GPS navigator, an efficient mobility management can be
possible by vehicles periodically reporting their current position performed with the help of vehicles periodically reporting their
and trajectory (i.e., navigation path) to the vehicular current position and trajectory (i.e., navigation path) to the
infrastructure (having RSUs and an MA in TCC) [ID-Vehicular-MM]. vehicular infrastructure (having IP-RSUs and an MA in TCC). This
This vehicular infrastructure can predict the future positions of the vehicular infrastructure can predict the future positions of the
vehicles with their mobility information (i.e., the current position, vehicles with their mobility information (i.e., the current position,
speed, direction, and trajectory) for the efficient mobility speed, direction, and trajectory) for the efficient mobility
management (e.g., proactive handover). For a better proactive management (e.g., proactive handover). For a better proactive
handover, link-layer parameters, such as the signal strength of a handover, link-layer parameters, such as the signal strength of a
link-layer frame (e.g., Received Channel Power Indicator (RCPI) link-layer frame (e.g., Received Channel Power Indicator (RCPI)
[VIP-WAVE]), can be used to determine the moment of a handover [VIP-WAVE]), can be used to determine the moment of a handover
between RSUs along with mobility information. between IP-RSUs along with mobility information.
By predicting a vehicle's mobility, the vehicular infrastructure can By predicting a vehicle's mobility, the vehicular infrastructure
better support RSUs to perform efficient DAD, data packet routing, needs to better support IP-RSUs to perform efficient SLAAC, data
horizontal handover (i.e., handover in wireless links using a forwarding, horizontal handover (i.e., handover in wireless links
homogeneous radio technology), and vertical handover (i.e., handover using a homogeneous radio technology), and vertical handover (i.e.,
in wireless links using heterogeneous radio technologies) in advance handover in wireless links using heterogeneous radio technologies) in
along with the movement of the vehicle [ID-Vehicular-MM]. For advance along with the movement of the vehicle.
example, when a vehicle is moving into the wireless link under
another RSU belonging to a different subnet, the RSU can proactively
perform the DAD for the sake of the vehicle, reducing IPv6 control
traffic overhead in the wireless link. To prevent a hacker from
impersonating RSUs as bogus RSUs, RSUs and MA in the vehicular
infrastructure need to have secure channels via IPsec.
Therefore, with a proactive handover and a multihop DAD in vehicular For example, as shown in Figure 1, when a vehicle (e.g., Vehicle2) is
networks, RSUs needs to efficiently forward data packets from the moving from the coverage of an IP-RSU (e.g., IP-RSU1) into the
wired network (or the wireless network) to a moving destination coverage of another IP-RSU (e.g., IP-RSU2) belonging to a different
vehicle along its trajectory. subnet, the IP-RSUs can proactively support the IPv6 mobility of the
vehicle, while performing the SLAAC, data forwarding, and handover
for the sake of the vehicle.
Therefore, for the proactive and seamless IPv6 mobility of vehicles,
the vehicular infrastructure (including IP-RSUs and MA) needs to
efficiently perform the mobility management of the vehicles with
their mobility information and link-layer information.
6. Security Considerations 6. Security Considerations
This section discusses security and privacy for IP-based vehicular This section discusses security and privacy for IPv6-based vehicular
networking. The security and privacy are one of key components in networking. The security and privacy is one of key components in
IP-based vehicular networking, such as neighbor discovery and IPv6-based vehicular networking along with neighbor discovery and
mobility management, so they need to be analyzed in depth. mobility management.
Security and privacy are paramount in the V2I, V2V, and V2X
networking. Only authorized vehicles need to be allowed to use the
vehicular networking. Also, in-vehicle devices (e.g., ECU) and
mobile devices (e.g., smartphone) in a vehicle need to communicate
with other in-vehicle devices and mobile devices in another vehicle,
and other servers in an IP-RSU in a secure way. Even a perfectly
authorized and legitimate vehicle may be hacked to run malicious
applications to track and collect its and other vehicles'
information. For this case, an attack mitigation process may be
required to reduce the aftermath of the malicious behaviors.
Strong security measures shall protect vehicles roaming in road Strong security measures shall protect vehicles roaming in road
networks from the attacks of malicious nodes, which are controlled by networks from the attacks of malicious nodes, which are controlled by
hackers. For safety applications, the cooperation among vehicles is hackers. For safety applications, the cooperation among vehicles is
assumed. Malicious nodes may disseminate wrong driving information assumed. Malicious nodes may disseminate wrong driving information
(e.g., location, speed, and direction) to make driving be unsafe. (e.g., location, speed, and direction) to make driving be unsafe.
Sybil attack, which tries to confuse a vehicle with multiple false
identities, disturbs a vehicle in taking a safe maneuver. This sybil
attack should be prevented through the cooperation between good
vehicles and RSUs. Note that good vehicles are ones with valid
certificates that are determined by the authentication process with
an authentication server in the vehicular network. Applications on
IP-based vehicular networking, which are resilient to such a sybil
attack, are not developed and tested yet.
Security and privacy are paramount in the V2I, V2V, and V2X For example, Sybil attack, which tries to confuse a vehicle with
networking in vehicular networks. Only authorized vehicles should be multiple false identities, disturbs a vehicle in taking a safe
allowed to use vehicular networking. Also, in-vehicle devices and maneuver. This sybil attack needs to be prevented through the
mobile devices in a vehicle need to communicate with other in-vehicle cooperation between good vehicles and IP-RSUs. Note that good
devices and mobile devices in another vehicle, and other servers in vehicles are ones with valid certificates that are determined by the
an RSU in a secure way. Even a perfectly authorized and legitimate authentication process with an authentication server in the vehicular
vehicle may be hacked to run malicious applications to track and cloud. However, applications on IPv6-based vehicular networking,
collect other vehicles' information. For this case, an attack which are resilient to such a sybil attack, are not developed and
mitigation process may be required to reduce the aftermath of the tested yet.
malicious behaviors.
A Vehicle Identification Number (VIN) and a user certificate along To identify the genuineness of vehicles against malicious vehicles,
with in-vehicle device's identifier generation can be used to an authentication method is required. A Vehicle Identification
efficiently authenticate a vehicle or a user through a road Number (VIN) and a user certificate along with in-vehicle device's
infrastructure node (e.g., RSU) connected to an authentication server identifier generation can be used to efficiently authenticate a
in TCC. Also, Transport Layer Security (TLS) certificates can be vehicle or a user through a road infrastructure node (e.g., IP-RSU)
used for secure E2E vehicle communications. connected to an authentication server in the vehicular cloud. Also,
Transport Layer Security (TLS) certificates can be used for the
vehicle authentication to allow secure E2E vehicle communications.
To identify the genuineness of vehicles against malicious vehicles,
an authentication method is required. For vehicle authentication,
information available from a vehicle or a driver (e.g., Vehicle
Identification Number (VIN) and Transport Layer Security (TLS)
certificate [RFC8446]) needs to be used to efficiently authenticate a
vehicle or a user with the help of a road infrastructure node (e.g.,
IP-RSU) connected to an authentication server in the vehicular cloud.
For secure V2I communication, a secure channel between a mobile For secure V2I communication, a secure channel between a mobile
router in a vehicle and a fixed router in an RSU should be router (i.e., IP-OBU) in a vehicle and a fixed router (i.e., IP-RSU)
established, as shown in Figure 2. Also, for secure V2V in an EN needs to be established, as shown in Figure 2. Also, for
communication, a secure channel between a mobile router in a vehicle secure V2V communication, a secure channel between a mobile router
and a mobile router in another vehicle should be established, as (i.e., IP-OBU) in a vehicle and a mobile router (i.e., IP-OBU) in
shown in Figure 3. another vehicle needs to be established, as shown in Figure 3.
To prevent an adversary from tracking a vehicle with its MAC address To prevent an adversary from tracking a vehicle with its MAC address
or IPv6 address, MAC address pseudonym should be provided to the or IPv6 address, MAC address pseudonym needs to be provided to the
vehicle; that is, each vehicle should periodically update its MAC vehicle; that is, each vehicle periodically updates its MAC address
address and the corresponding IPv6 address as suggested in and the corresponding IPv6 address [RFC4086][RFC4941]. Such an
[RFC4086][RFC4941]. Such an update of the MAC and IPv6 addresses update of the MAC and IPv6 addresses should not interrupt the E2E
should not interrupt the E2E communications between two vehicles (or communications between two vehicles (or between a vehicle and an IP-
between a vehicle and an RSU) in terms of transport layer for a long- RSU) for a long-living transport-layer session. However, if this
living higher-layer session. However, if this pseudonym is performed pseudonym is performed without strong E2E confidentiality, there will
without strong E2E confidentiality, there will be no privacy benefit be no privacy benefit from changing MAC and IPv6 addresses, because
from changing MAC and IP addresses, because an adversary can see the an adversary can observe the change of the MAC and IPv6 addresses and
change of the MAC and IP addresses and track the vehicle with those track the vehicle with those addresses.
addresses.
For the IPv6 ND, the vehicular-network-wide DAD is required for the For the IPv6 ND, the DAD is required for the uniqueness of the IPv6
uniqueness of the IPv6 address of a vehicle's wireless interface. address of a vehicle's wireless interface. This DAD can be used as a
This DAD can be used as a flooding attack that makes the DAD-related flooding attack that makes the DAD-related ND packets are
ND packets are disseminated over the VANET and vehicular network disseminated over the VANET or vehicular networks. Thus, the
including the RSUs and the MA. The vehicles and RSUs need to filter vehicles and IP-RSUs need to filter out suspicious ND traffic in
out suspicious ND traffic in advance. advance.
For the mobility management, a malicious vehicle can construct For the mobility management, a malicious vehicle can construct
multiple virtual bogus vehicles, and register them with the RSU and multiple virtual bogus vehicles, and register them with IP-RSUs and
the MA. This registration makes the RSU and MA waste their MA. This registration makes the IP-RSUs and MA waste their
resources. The RSU and MA need to determine whether a vehicle is resources. The IP-RSUs and MA need to determine whether a vehicle is
genuine or bogus in the mobility management. genuine or bogus in the mobility management. Also, the
confidentiality of control packets and data packets among IP-RSUs and
MA, the E2E paths (e.g., tunnels) need to be protected by secure
communication channels. In addition, to prevent bogus IP-RSUs and MA
from interfering IPv6 mobility of vehicles, the mutual authentication
among them needs to be performed by certificates (e.g., TLS
certificate).
7. Informative References 7. Informative References
[Automotive-Sensing] [Automotive-Sensing]
Choi, J., Va, V., Gonzalez-Prelcic, N., Daniels, R., R. Choi, J., Va, V., Gonzalez-Prelcic, N., Daniels, R., R.
Bhat, C., and R. W. Heath, "Millimeter-Wave Vehicular Bhat, C., and R. W. Heath, "Millimeter-Wave Vehicular
Communication to Support Massive Automotive Sensing", Communication to Support Massive Automotive Sensing",
IEEE Communications Magazine, December 2016. IEEE Communications Magazine, December 2016.
[CA-Cruise-Control] [CA-Cruise-Control]
skipping to change at page 22, line 39 skipping to change at page 24, line 32
[Fuel-Efficient] [Fuel-Efficient]
van de Hoef, S., H. Johansson, K., and D. V. Dimarogonas, van de Hoef, S., H. Johansson, K., and D. V. Dimarogonas,
"Fuel-Efficient En Route Formation of Truck Platoons", "Fuel-Efficient En Route Formation of Truck Platoons",
IEEE Transactions on Intelligent Transportation Systems, IEEE Transactions on Intelligent Transportation Systems,
January 2018. January 2018.
[ID-Multicast-Problems] [ID-Multicast-Problems]
Perkins, C., McBride, M., Stanley, D., Kumari, W., and JC. Perkins, C., McBride, M., Stanley, D., Kumari, W., and JC.
Zuniga, "Multicast Considerations over IEEE 802 Wireless Zuniga, "Multicast Considerations over IEEE 802 Wireless
Media", draft-ietf-mboned-ieee802-mcast-problems-06 (work Media", draft-ietf-mboned-ieee802-mcast-problems-11 (work
in progress), July 2019. in progress), December 2019.
[ID-Vehicular-MM]
Jeong, J., Ed., Shen, Y., and Z. Xiang, "Vehicular
Mobility Management for IP-Based Vehicular Networks",
draft-jeong-ipwave-vehicular-mobility-management-01 (work
in progress), July 2019.
[ID-Vehicular-ND]
Jeong, J., Ed., Shen, Y., and Z. Xiang, "Vehicular
Neighbor Discovery for IP-Based Vehicular Networks",
draft-jeong-ipwave-vehicular-neighbor-discovery-07 (work
in progress), July 2019.
[Identity-Management] [Identity-Management]
Wetterwald, M., Hrizi, F., and P. Cataldi, "Cross-layer Wetterwald, M., Hrizi, F., and P. Cataldi, "Cross-layer
Identities Management in ITS Stations", The 10th Identities Management in ITS Stations", The 10th
International Conference on ITS Telecommunications, International Conference on ITS Telecommunications,
November 2010. November 2010.
[IEEE-802.11-OCB] [IEEE-802.11-OCB]
"Part 11: Wireless LAN Medium Access Control (MAC) and "Part 11: Wireless LAN Medium Access Control (MAC) and
Physical Layer (PHY) Specifications", IEEE Std Physical Layer (PHY) Specifications", IEEE Std
802.11-2016, December 2016. 802.11-2016, December 2016.
[IEEE-802.11p] [IEEE-802.11p]
"Part 11: Wireless LAN Medium Access Control (MAC) and "Part 11: Wireless LAN Medium Access Control (MAC) and
Physical Layer (PHY) Specifications - Amendment 6: Physical Layer (PHY) Specifications - Amendment 6:
Wireless Access in Vehicular Environments", IEEE Std Wireless Access in Vehicular Environments", IEEE Std
802.11p-2010, June 2010. 802.11p-2010, June 2010.
[Intro-to-Algorithms]
H. Cormen, T., E. Leiserson, C., L. Rivest, R., and C.
Stein, "Introduction to Algorithms, 3rd ed.", The
MIT Press, July 2009.
[IPv6-over-802.11-OCB]
Benamar, N., Haerri, J., Lee, J., and T. Ernst, "Basic
Support for IPv6 over IEEE Std 802.11 Networks Operating
Outside the Context of a Basic Service Set (IPv6-over-
80211-OCB)", draft-ietf-ipwave-ipv6-over-80211ocb-49 (work
in progress), July 2019.
[ISO-ITS-IPv6] [ISO-ITS-IPv6]
ISO/TC 204, "Intelligent Transport Systems - ISO/TC 204, "Intelligent Transport Systems -
Communications Access for Land Mobiles (CALM) - IPv6 Communications Access for Land Mobiles (CALM) - IPv6
Networking", ISO 21210:2012, June 2012. Networking", ISO 21210:2012, June 2012.
[NHTSA-ACAS-Report] [NHTSA-ACAS-Report]
National Highway Traffic Safety Administration (NHTSA), National Highway Traffic Safety Administration (NHTSA),
"Final Report of Automotive Collision Avoidance Systems "Final Report of Automotive Collision Avoidance Systems
(ACAS) Program", DOT HS 809 080, August 2000. (ACAS) Program", DOT HS 809 080, August 2000.
[RFC3561] Perkins, C., Belding-Royer, E., and S. Das, "Ad hoc On- [RFC3561] Perkins, C., Belding-Royer, E., and S. Das, "Ad hoc On-
Demand Distance Vector (AODV) Routing", RFC 3561, July Demand Distance Vector (AODV) Routing", RFC 3561, July
2003. 2003.
[RFC3753] Manner, J. and M. Kojo, "Mobility Related Terminology",
RFC 3753, June 2004.
[RFC3849] Huston, G., Lord, A., and P. Smith, "IPv6 Address Prefix [RFC3849] Huston, G., Lord, A., and P. Smith, "IPv6 Address Prefix
Reserved for Documentation", RFC 3849, July 2004. Reserved for Documentation", RFC 3849, July 2004.
[RFC4086] Eastlake 3rd, D., Schiller, J., and S. Crocker, [RFC4086] Eastlake 3rd, D., Schiller, J., and S. Crocker,
"Randomness Requirements for Security", RFC 4086, June "Randomness Requirements for Security", RFC 4086, June
2005. 2005.
[RFC4861] Narten, T., Nordmark, E., Simpson, W., and H. Soliman, [RFC4861] Narten, T., Nordmark, E., Simpson, W., and H. Soliman,
"Neighbor Discovery for IP Version 6 (IPv6)", RFC 4861, "Neighbor Discovery for IP Version 6 (IPv6)", RFC 4861,
September 2007. September 2007.
skipping to change at page 24, line 24 skipping to change at page 25, line 44
Address Autoconfiguration", RFC 4862, September 2007. Address Autoconfiguration", RFC 4862, September 2007.
[RFC4941] Narten, T., Draves, R., and S. Krishnan, "Privacy [RFC4941] Narten, T., Draves, R., and S. Krishnan, "Privacy
Extensions for Stateless Address Autoconfiguration in Extensions for Stateless Address Autoconfiguration in
IPv6", RFC 4941, September 2007. IPv6", RFC 4941, September 2007.
[RFC5213] Gundavelli, S., Ed., Leung, K., Devarapalli, V., [RFC5213] Gundavelli, S., Ed., Leung, K., Devarapalli, V.,
Chowdhury, K., and B. Patil, "Proxy Mobile IPv6", Chowdhury, K., and B. Patil, "Proxy Mobile IPv6",
RFC 5213, August 2008. RFC 5213, August 2008.
[RFC5844] Wakikawa, R. and S. Gundavelli, "IPv4 Support for Proxy [RFC5415] Calhoun, P., Montemurro, M., and D. Stanley, "Control And
Mobile IPv6", RFC 5844, May 2010. Provisioning of Wireless Access Points (CAPWAP) Protocol
Specification", RFC 5415, March 2009.
[RFC5889] Baccelli, E. and M. Townsley, "IP Addressing Model in Ad [RFC5889] Baccelli, E. and M. Townsley, "IP Addressing Model in Ad
Hoc Networks", RFC 5889, September 2010. Hoc Networks", RFC 5889, September 2010.
[RFC5944] Perkins, C., Ed., "IP Mobility Support in IPv4, Revised",
RFC 5944, November 2010.
[RFC6250] Thaler, D., "Evolution of the IP Model", RFC 6250, May [RFC6250] Thaler, D., "Evolution of the IP Model", RFC 6250, May
2011. 2011.
[RFC6275] Perkins, C., Ed., Johnson, D., and J. Arkko, "Mobility [RFC6275] Perkins, C., Ed., Johnson, D., and J. Arkko, "Mobility
Support in IPv6", RFC 6275, July 2011. Support in IPv6", RFC 6275, July 2011.
[RFC6775] Shelby, Z., Chakrabarti, S., Nordmark, E., and C. Bormann, [RFC6775] Shelby, Z., Chakrabarti, S., Nordmark, E., and C. Bormann,
"Neighbor Discovery Optimization for IPv6 over Low-Power "Neighbor Discovery Optimization for IPv6 over Low-Power
Wireless Personal Area Networks (6LoWPANs)", RFC 6775, Wireless Personal Area Networks (6LoWPANs)", RFC 6775,
November 2012. November 2012.
[RFC7149] Boucadair, M. and C. Jacquenet, "Software-Defined
Networking: A Perspective from within a Service Provider
Environment", RFC 7149, March 2014.
[RFC7181] Clausen, T., Dearlove, C., Jacquet, P., and U. Herberg, [RFC7181] Clausen, T., Dearlove, C., Jacquet, P., and U. Herberg,
"The Optimized Link State Routing Protocol Version 2", "The Optimized Link State Routing Protocol Version 2",
RFC 7181, April 2014. RFC 7181, April 2014.
[RFC8200] Deering, S. and R. Hinden, "Internet Protocol, Version 6 [RFC8200] Deering, S. and R. Hinden, "Internet Protocol, Version 6
(IPv6) Specification", RFC 8200, July 2017. (IPv6) Specification", RFC 8200, July 2017.
[RFC8446] Rescorla, E., "The Transport Layer Security (TLS) Protocol
Version 1.3", RFC 8446, August 2018.
[RFC8691] Benamar, N., Haerri, J., Lee, J., and T. Ernst, "Basic
Support for IPv6 Networks Operating Outside the Context of
a Basic Service Set over IEEE Std 802.11", RFC 8691,
December 2019.
[SAINT] Jeong, J., Jeong, H., Lee, E., Oh, T., and D. Du, "SAINT: [SAINT] Jeong, J., Jeong, H., Lee, E., Oh, T., and D. Du, "SAINT:
Self-Adaptive Interactive Navigation Tool for Cloud-Based Self-Adaptive Interactive Navigation Tool for Cloud-Based
Vehicular Traffic Optimization", IEEE Transactions on Vehicular Traffic Optimization", IEEE Transactions on
Vehicular Technology, Vol. 65, No. 6, June 2016. Vehicular Technology, Vol. 65, No. 6, June 2016.
[SAINTplus] [SAINTplus]
Shen, Y., Lee, J., Jeong, H., Jeong, J., Lee, E., and D. Shen, Y., Lee, J., Jeong, H., Jeong, J., Lee, E., and D.
Du, "SAINT+: Self-Adaptive Interactive Navigation Tool+ Du, "SAINT+: Self-Adaptive Interactive Navigation Tool+
for Emergency Service Delivery Optimization", for Emergency Service Delivery Optimization",
IEEE Transactions on Intelligent Transportation Systems, IEEE Transactions on Intelligent Transportation Systems,
skipping to change at page 27, line 5 skipping to change at page 29, line 5
[WAVE-1609.3] [WAVE-1609.3]
IEEE 1609 Working Group, "IEEE Standard for Wireless IEEE 1609 Working Group, "IEEE Standard for Wireless
Access in Vehicular Environments (WAVE) - Networking Access in Vehicular Environments (WAVE) - Networking
Services", IEEE Std 1609.3-2016, April 2016. Services", IEEE Std 1609.3-2016, April 2016.
[WAVE-1609.4] [WAVE-1609.4]
IEEE 1609 Working Group, "IEEE Standard for Wireless IEEE 1609 Working Group, "IEEE Standard for Wireless
Access in Vehicular Environments (WAVE) - Multi-Channel Access in Vehicular Environments (WAVE) - Multi-Channel
Operation", IEEE Std 1609.4-2016, March 2016. Operation", IEEE Std 1609.4-2016, March 2016.
Appendix A. Changes from draft-ietf-ipwave-vehicular-networking-11 Appendix A. Changes from draft-ietf-ipwave-vehicular-networking-12
The following changes are made from draft-ietf-ipwave-vehicular- The following changes are made from draft-ietf-ipwave-vehicular-
networking-11: networking-12:
o This version is revised based on the comments from Charlie Perkins
and Sandra Cespedes.
o In Section 5, the problem statement is revisd with easily
identifiable problems.
o In Section 1, the description of GeoNetworking (GN) protocols
(i.e., geographic routing) is removed because the GN protocols are
not relevant to the IPWAVE's use cases.
o In Section 2, the terms of OCB, Context-Awareness, Platooning, and
Class-Based Safety Plan are clarified.
o In Section 2, the definition of an RSU is revised so that it can
accommodate multiple routers (or switches) and servers (including
DNS server and edge computing server) as an edge computing system
because the RSU is regularly a router or switch.
o In Section 4.1, a general vehicular network architecture is
proposed for the problem statement along with Figure 1. This
figure clarifies that a single subnet prefix can span multiple
vehicles that construct a subnet. Also, some components in the
vehicular network architecture may not be needed such as Vehicular
Cloud, Traffic Control Center, and Mobility Anchor.
o In Section 5.1.1, the motivation of a new link model as a
vehicular link model is added. The "on-link" and "off-link" for
prefixes are classified according to the subnet topology of VANET.
o In Section 5.1.1, the merging and partitioning of VANETs is
described, and the requirements of the IPv6 ND are addressed for
the merging and partitioning as a problem statement.
o In Section 5.1.2, a citation of [Scrambler-Attack], which uses the
scrambler seed in the IEEE 802.11-OCB frames as fingerprint
information, is added to show the insufficiency of the MAC address
pseudonym for privacy.
o In Section 5.1, the subsection of Prefix Dissemination/Exchange is
removed because the Prefix Dissemination/Exchange subsection
discusses a solution rather than a problem or requirement.
o In Section 5.1.3, the motivation of merging the IPv6 ND and a o This version is revised based on the comments from Carlos
VANET routing protocol is explained to improve wireless channel Bernardos.
utilization by removing redundant neighbor information exchange.
o The text of the problems and requirements of security and privacy o This version focuses on problems rather than solutions for IPWAVE.
in vehicular networks are moved to Section 6. Also, this version addresses the requirements of IPv6 neighbor
discovery, mobility management, and security and privacy.
o In Section 6, the compromise of a perfectly authorized and o In Section 2, IP-OBU and IP-RSU are used instead of OBU and RSU,
legitimate vehicle is described as a security problem to be respectively.
considered.
o In Section 3.3, the description of Vehicle-to-Pedestrian (V2P) is o In Section 4.1, an exemplary vehicular network architecture is
concised to deliver the clear concept of the direct communication illustrated for the problem statement as Figure 1.
between a vehicle and a pedestrian.
Appendix B. Acknowledgments Appendix B. Acknowledgments
This work was supported by Basic Science Research Program through the This work was supported by Basic Science Research Program through the
National Research Foundation of Korea (NRF) funded by the Ministry of National Research Foundation of Korea (NRF) funded by the Ministry of
Education (2017R1D1A1B03035885). Education (2017R1D1A1B03035885).
This work was supported in part by the MSIT (Ministry of Science and This work was supported in part by the MSIT (Ministry of Science and
ICT), Korea, under the ITRC (Information Technology Research Center) ICT), Korea, under the ITRC (Information Technology Research Center)
support program (IITP-2019-2017-0-01633) supervised by the IITP support program (IITP-2019-2017-0-01633) supervised by the IITP
skipping to change at page 28, line 43 skipping to change at page 29, line 46
by the European Commission I (636537-H2020). by the European Commission I (636537-H2020).
Appendix C. Contributors Appendix C. Contributors
This document is a group work of IPWAVE working group, greatly This document is a group work of IPWAVE working group, greatly
benefiting from inputs and texts by Rex Buddenberg (Naval benefiting from inputs and texts by Rex Buddenberg (Naval
Postgraduate School), Thierry Ernst (YoGoKo), Bokor Laszlo (Budapest Postgraduate School), Thierry Ernst (YoGoKo), Bokor Laszlo (Budapest
University of Technology and Economics), Jose Santa Lozanoi University of Technology and Economics), Jose Santa Lozanoi
(Universidad of Murcia), Richard Roy (MIT), Francois Simon (Pilot), (Universidad of Murcia), Richard Roy (MIT), Francois Simon (Pilot),
Sri Gundavelli (Cisco), Erik Nordmark, Dirk von Hugo (Deutsche Sri Gundavelli (Cisco), Erik Nordmark, Dirk von Hugo (Deutsche
Telekom), and Pascal Thubert (Cisco). The authors sincerely Telekom), Pascal Thubert (Cisco), Carlos Bernardos (UC3M), Russ
appreciate their contributions. Housley (Vigil Security), and Suresh Krishnan (Kaloom). The authors
sincerely appreciate their contributions.
The following are co-authors of this document: The following are co-authors of this document:
Nabil Benamar Nabil Benamar
Department of Computer Sciences Department of Computer Sciences
High School of Technology of Meknes High School of Technology of Meknes
Moulay Ismail University Moulay Ismail University
Morocco Morocco
Phone: +212 6 70 83 22 36 Phone: +212 6 70 83 22 36
EMail: benamar73@gmail.com EMail: benamar73@gmail.com
Sandra Cespedes Sandra Cespedes
NIC Chile Research Labs NIC Chile Research Labs
Universidad de Chile Universidad de Chile
Av. Blanco Encalada 1975 Av. Blanco Encalada 1975
Santiago Santiago
Chile Chile
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