draft-ietf-ipwave-vehicular-networking-08.txt   draft-ietf-ipwave-vehicular-networking-09.txt 
IPWAVE Working Group J. Jeong, Ed. IPWAVE Working Group J. Jeong, Ed.
Internet-Draft Sungkyunkwan University Internet-Draft Sungkyunkwan University
Intended status: Informational March 24, 2019 Intended status: Informational May 24, 2019
Expires: September 25, 2019 Expires: November 25, 2019
IP Wireless Access in Vehicular Environments (IPWAVE): Problem Statement IP Wireless Access in Vehicular Environments (IPWAVE): Problem Statement
and Use Cases and Use Cases
draft-ietf-ipwave-vehicular-networking-08 draft-ietf-ipwave-vehicular-networking-09
Abstract Abstract
This document discusses the problem statement and use cases of IP- This document discusses the problem statement and use cases of IP-
based vehicular networking for Intelligent Transportation Systems based vehicular networking for Intelligent Transportation Systems
(ITS). The main scenarios of vehicular communications are vehicle- (ITS). The main scenarios of vehicular communications are vehicle-
to-vehicle (V2V), vehicle-to-infrastructure (V2I), and vehicle-to- to-vehicle (V2V), vehicle-to-infrastructure (V2I), and vehicle-to-
everything (V2X) communications. First, this document surveys use everything (V2X) communications. First, this document explains use
cases using V2V, V2I, and V2X networking. Second, it analyzes cases using V2V, V2I, and V2X networking. Next, it makes a problem
proposed protocols for IP-based vehicular networking and highlights statement about key aspects in IP-based vehicular networking, such as
the limitations and difficulties found on those protocols. Third, it IPv6 Neighbor Discovery, Mobility Management, and Security & Privacy.
presents a problem exploration for key aspects in IP-based vehicular For each key aspect, this document specifies requirements in IP-based
networking, such as IPv6 Neighbor Discovery, Mobility Management, and vehicular networking, and suggests the direction of solutions
Security & Privacy. For each key aspect, this document discusses a satisfying those requirements.
problem statement to evaluate the gap between the state-of-the-art
techniques and requirements in IP-based vehicular networking.
Status of This Memo Status of This Memo
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This Internet-Draft will expire on September 25, 2019. This Internet-Draft will expire on November 25, 2019.
Copyright Notice Copyright Notice
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Use Cases . . . . . . . . . . . . . . . . . . . . . . . . . . 5 3. Use Cases . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3.1. V2V . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 3.1. V2V . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3.2. V2I . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 3.2. V2I . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.3. V2X . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 3.3. V2X . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
4. Analysis for Existing Protocols . . . . . . . . . . . . . . . 8 4. Vehicular Networks . . . . . . . . . . . . . . . . . . . . . 7
4.1. Existing Protocols for Vehicular Networking . . . . . . . 8 4.1. Vehicular Network Architecture . . . . . . . . . . . . . 8
4.1.1. IP Address Autoconfiguration . . . . . . . . . . . . 8 4.2. V2I-based Internetworking . . . . . . . . . . . . . . . . 9
4.1.2. Routing Protocol . . . . . . . . . . . . . . . . . . 9 4.3. V2V-based Internetworking . . . . . . . . . . . . . . . . 11
4.1.3. Mobility Management . . . . . . . . . . . . . . . . . 10 5. Problem Statement . . . . . . . . . . . . . . . . . . . . . . 13
4.1.4. DNS Naming Service . . . . . . . . . . . . . . . . . 11 5.1. Neighbor Discovery . . . . . . . . . . . . . . . . . . . 13
4.1.5. Service Discovery . . . . . . . . . . . . . . . . . . 12 5.1.1. Link Model . . . . . . . . . . . . . . . . . . . . . 14
4.1.6. Security and Privacy . . . . . . . . . . . . . . . . 12 5.1.2. MAC Address Pseudonym . . . . . . . . . . . . . . . . 16
4.2. General Problems . . . . . . . . . . . . . . . . . . . . 13 5.1.3. Prefix Dissemination/Exchange . . . . . . . . . . . . 16
4.2.1. Vehicular Network Architecture . . . . . . . . . . . 14 5.1.4. Routing . . . . . . . . . . . . . . . . . . . . . . . 17
4.2.2. Latency . . . . . . . . . . . . . . . . . . . . . . . 19 5.2. Mobility Management . . . . . . . . . . . . . . . . . . . 17
4.2.3. Security . . . . . . . . . . . . . . . . . . . . . . 20 5.3. Security and Privacy . . . . . . . . . . . . . . . . . . 18
4.2.4. Pseudonym Handling . . . . . . . . . . . . . . . . . 20 6. Security Considerations . . . . . . . . . . . . . . . . . . . 19
5. Problem Exploration . . . . . . . . . . . . . . . . . . . . . 20 7. Informative References . . . . . . . . . . . . . . . . . . . 19
5.1. Neighbor Discovery . . . . . . . . . . . . . . . . . . . 20 Appendix A. Changes from draft-ietf-ipwave-vehicular-
5.1.1. Link Model . . . . . . . . . . . . . . . . . . . . . 21 networking-08 . . . . . . . . . . . . . . . . . . . 25
5.1.2. MAC Address Pseudonym . . . . . . . . . . . . . . . . 22 Appendix B. Acknowledgments . . . . . . . . . . . . . . . . . . 25
5.1.3. Prefix Dissemination/Exchange . . . . . . . . . . . . 22 Appendix C. Contributors . . . . . . . . . . . . . . . . . . . . 25
5.1.4. Routing . . . . . . . . . . . . . . . . . . . . . . . 22 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 27
5.2. Mobility Management . . . . . . . . . . . . . . . . . . . 23
5.3. Security and Privacy . . . . . . . . . . . . . . . . . . 24
6. Security Considerations . . . . . . . . . . . . . . . . . . . 24
7. Informative References . . . . . . . . . . . . . . . . . . . 25
Appendix A. Relevant Topics to IPWAVE Working Group . . . . . . 33
A.1. Vehicle Identity Management . . . . . . . . . . . . . . . 33
A.2. Multihop V2X . . . . . . . . . . . . . . . . . . . . . . 33
A.3. Multicast . . . . . . . . . . . . . . . . . . . . . . . . 33
A.4. DNS Naming Services and Service Discovery . . . . . . . . 34
A.5. IPv6 over Cellular Networks . . . . . . . . . . . . . . . 34
A.5.1. Cellular V2X (C-V2X) Using 4G-LTE . . . . . . . . . . 34
A.5.2. Cellular V2X (C-V2X) Using 5G . . . . . . . . . . . . 35
Appendix B. Changes from draft-ietf-ipwave-vehicular-
networking-07 . . . . . . . . . . . . . . . . . . . 35
Appendix C. Acknowledgments . . . . . . . . . . . . . . . . . . 35
Appendix D. Contributors . . . . . . . . . . . . . . . . . . . . 36
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 38
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], service in the Intelligent Transportation Systems (DSRC) [DSRC] in the Intelligent Transportation Systems (ITS) with
(ITS) Radio Service in the 5.850 - 5.925 GHz band (5.9 GHz band). the frequency band of 5.850 - 5.925 GHz (i.e., 5.9 GHz band). DSRC-
DSRC-based wireless communications can support vehicle-to-vehicle based wireless communications can support vehicle-to-vehicle (V2V),
(V2V), vehicle-to-infrastructure (V2I), and vehicle-to-everything vehicle-to-infrastructure (V2I), and vehicle-to-everything (V2X)
(V2X) networking. Also, the European Union (EU) passed a decision to networking. Also, the European Union (EU) passed a decision to
allocate radio spectrum for safety-related and non-safety-related allocate a radio spectrum for safety-related and non-safety-related
applications of ITS with the frequency band of 5.875 - 5.905 GHz, applications of ITS with the frequency band of 5.875 - 5.905 GHz,
which is called Commission Decision 2008/671/EC [EU-2008-671-EC]. which is called Commission Decision 2008/671/EC [EU-2008-671-EC].
For direct inter-vehicular wireless connectivity, IEEE has amended For direct inter-vehicular wireless connectivity, IEEE has amended
WiFi standard 802.11 to enable driving safety services based on the WiFi standard 802.11 to enable driving safety services based on the
DSRC in terms of standards for the Wireless Access in Vehicular DSRC in terms of standards for the Wireless Access in Vehicular
Environments (WAVE) system. The Physical Layer (L1) and Data Link Environments (WAVE) system. The Physical Layer (L1) and Data Link
Layer (L2) issues are addressed in IEEE 802.11p [IEEE-802.11p] for Layer (L2) issues are addressed in IEEE 802.11p [IEEE-802.11p] for
the PHY and MAC of the DSRC, while IEEE 1609.2 [WAVE-1609.2] covers the PHY and MAC of the DSRC, while IEEE 1609.2 [WAVE-1609.2] covers
security aspects, IEEE 1609.3 [WAVE-1609.3] defines related services security aspects, IEEE 1609.3 [WAVE-1609.3] defines related services
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(PMIPv6) [RFC5213][RFC5844]) can be applied (or easily modified) to (PMIPv6) [RFC5213][RFC5844]) can be applied (or easily modified) to
vehicular networks. In Europe, ETSI has standardized a GeoNetworking vehicular networks. In Europe, ETSI has standardized a GeoNetworking
(GN) protocol [ETSI-GeoNetworking] and a protocol adaptation sub- (GN) protocol [ETSI-GeoNetworking] and a protocol adaptation sub-
layer from GeoNetworking to IPv6 [ETSI-GeoNetwork-IP]. Note that a layer from GeoNetworking to IPv6 [ETSI-GeoNetwork-IP]. Note that a
GN protocol is useful to route an event or notification message to GN protocol is useful to route an event or notification message to
vehicles around a geographic position, such as an acciendent area in vehicles around a geographic position, such as an acciendent area in
a roadway. In addition, ISO has approved a standard specifying the a roadway. In addition, ISO has approved a standard specifying the
IPv6 network protocols and services to be used for Communications IPv6 network protocols and services to be used for Communications
Access for Land Mobiles (CALM) [ISO-ITS-IPv6]. Access for Land Mobiles (CALM) [ISO-ITS-IPv6].
This document discusses problem statements and use cases related to This document explains use cases and a problem statement about IP-
IP-based vehicular networking for Intelligent Transportation Systems based vehicular networking for ITS, which is named IP Wireless Access
(ITS), which is denoted as IP Wireless Access in Vehicular in Vehicular Environments (IPWAVE). First, it introduces the use
Environments (IPWAVE). First, it surveys the use cases for using cases for using V2V, V2I, and V2X networking in the ITS. Next, it
V2V, V2I, and V2X networking in the ITS. Second, for literature makes a problem statement about key aspects in IPWAVE, such as IPv6
review, it analyzes proposed protocols for IP-based vehicular Neighbor Discovery, Mobility Management, and Security & Privacy. For
networking and highlights the limitations and difficulties found on each key aspect of the problem statement, this document specifies
those protocols. Third, for problem statement, it presents a problem requirements in IP-based vehicular networking, and proposes the
exploration with key aspects in IPWAVE, such as IPv6 Neighbor direction of solutions fulfilling those requirements. Therefore,
Discovery, Mobility Management, and Security & Privacy. For each key with the problem statement, this document will open a door to develop
aspect of the problem statement, it analyzes the gap between the key protocols for IPWAVE that will be essential to IP-based vehicular
state-of-the-art techniques and the requirements in IP-based networks in near future.
vehicular networking. It also discusses potential topics relevant to
IPWAVE Working Group (WG), such as Vehicle Identities Management,
Multihop V2X Communications, Multicast, DNS Naming Services, Service
Discovery, and IPv6 over Cellular Networks. Therefore, with the
problem statement, this document will open a door to develop key
protocols for IPWAVE that will be essential to IP-based vehicular
networks.
2. Terminology 2. Terminology
This document uses the following definitions: This document uses the following definitions:
o DMM: Acronym for "Distributed Mobility Management" o DMM: Acronym for "Distributed Mobility Management"
[RFC7333][RFC7429]. [RFC7333][RFC7429].
o LiDAR: Acronym for "Light Detection and Ranging". It is a o LiDAR: Acronym for "Light Detection and Ranging". It is a
scanning device to measure a distance to an object by emitting scanning device to measure a distance to an object by emitting
pulsed laser light and measuring the reflected pulsed light. pulsed laser light and measuring the reflected pulsed light.
o Mobility Anchor (MA): A node that maintains IP addresses and o Mobility Anchor (MA): A node that maintains IP 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 address autoconfiguration and mobility management with a
binding table. It has end-to-end connections with RSUs under its binding table. It has end-to-end connections with RSUs under its
control. control.
o On-Board Unit (OBU): A node that has (e.g., IEEE 802.11-OCB and o On-Board Unit (OBU): A node that has physical communication
Cellular V2X (C-V2X) [TS-23.285-3GPP]) for wireless communications devices (e.g., IEEE 802.11-OCB and Cellular V2X (C-V2X)
with other OBUs and RSUs, and may be connected to in-vehicle [TS-23.285-3GPP]) for wireless communications with other OBUs and
devices or networks. An OBU is mounted on a vehicle. It is RSUs, and may be connected to in-vehicle devices or networks. An
assumed that a radio navigation receiver (e.g., Global Positioning OBU is mounted on a vehicle.
System (GPS)) is included in a vehicle with an OBU for efficient
navigation.
o OCB: Acronym for "Outside the Context of a Basic Service Set" o OCB: Acronym for "Outside the Context of a Basic Service Set"
[IEEE-802.11-OCB]. [IEEE-802.11-OCB].
o Road-Side Unit (RSU): A node that has physical communication o Road-Side Unit (RSU): A node that has physical communication
devices (e.g., IEEE 802.11-OCB and C-V2X) for wireless devices (e.g., IEEE 802.11-OCB and C-V2X) for wireless
communications with vehicles and is also connected to the Internet communications with vehicles and is also connected to the Internet
as a router or switch for packet forwarding. An RSU is typically as a router or switch for packet forwarding. An RSU is typically
deployed on the road infrastructure, either at an intersection or deployed on the road infrastructure, either at an intersection or
in a road segment, but may also be located in car parking area. in a road segment, but may also be located in 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., RSUs, traffic signals, and loop
detectors), vehicular traffic statistics (e.g., average vehicle detectors), vehicular traffic statistics (e.g., average vehicle
speed and vehicle inter-arrival time per road segment), and speed and vehicle inter-arrival time per road segment), and
vehicle information (e.g., a vehicle's identifier, position, 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 node that has an OBU for wireless communication with
other vehicles and RSUs. It has a radio navigation receiver of
Global Positioning System (GPS) for efficient navigation.
o Vehicular Ad Hoc Network (VANET): A network that consists of
vehicles interconnected by wireless communication. Since VANET is
a connected network component, two vehicles in a VANET can
communicate with each other through ad hoc routing via other
vehicles as relays even where they are out of one-hop wireless
communication 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 nodes. having compute nodes, storage nodes, and network nodes.
o Vehicle Detection Loop (or 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 approaching a traffic light or in motorway point, for instance, at an intersection with traffic lights or at
traffic. The relatively crude nature of the loop's structure a ramp toward a highway. The relatively crude nature of the
means that only metal masses above a certain size are capable of loop's structure means that only metal masses above a certain size
triggering the detection. are capable of triggering the detection.
o V2I2P: Acronym for "Vehicle to Infrastructure to Pedestrian". o V2I2P: Acronym for "Vehicle to Infrastructure to Pedestrian".
o V2I2V: Acronym for "Vehicle to Infrastructure to Vehicle". o V2I2V: Acronym for "Vehicle to Infrastructure to Vehicle".
o WAVE: Acronym for "Wireless Access in Vehicular Environments" o WAVE: Acronym for "Wireless Access in Vehicular Environments"
[WAVE-1609.0]. [WAVE-1609.0].
3. Use Cases 3. Use Cases
This section provides 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).
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;
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These four techniques will be important elements for self-driving These four techniques will be important elements for self-driving
vehicles. vehicles.
Context-Aware Safety Driving (CASD) navigator [CASD] can help drivers Context-Aware Safety Driving (CASD) navigator [CASD] can help drivers
to drive safely by letting the drivers recognize dangerous obstacles to drive safely by letting the drivers recognize dangerous obstacles
and situations. That is, CASD navigator displays obstables or and situations. That is, CASD navigator displays obstables or
neighboring vehicles relevant to possible collisions in real-time neighboring vehicles relevant to possible collisions in real-time
through V2V networking. CASD provides vehicles with a class-based through V2V networking. CASD provides vehicles with a class-based
automatic safety action plan, which considers three situations, such automatic safety action plan, which considers three situations, such
as the Line-of-Sight unsafe, Non-Line-of-Sight unsafe and safe as the Line-of-Sight unsafe, Non-Line-of-Sight unsafe, and safe
situations. This action plan can be performed among vehicles through situations. This action plan can be performed among vehicles through
V2V networking. V2V networking.
Cooperative Adaptive Cruise Control (CACC) [CA-Cruise-Control] helps Cooperative Adaptive Cruise Control (CACC) [CA-Cruise-Control] helps
vehicles to adapt their speed autonomously through V2V communication vehicles to adapt their speed autonomously through V2V communication
among vehicles according to the mobility of their predecessor and among vehicles according to the mobility of their predecessor and
successor vehicles in an urban roadway or a highway. Thus, CACC can successor vehicles in an urban roadway or a highway. Thus, CACC can
help adjacent vehicles to efficiently adjust their speed in an help adjacent vehicles to efficiently adjust their speed in an
interactive way through V2V networking in order to avoid collision. interactive way through V2V networking in order to avoid collision.
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trucks) to move together with a very short inter-distance. Trucks trucks) to move together with a very short inter-distance. Trucks
can use V2V communication in addition to forward sensors in order to can use V2V communication in addition to forward sensors in order to
maintain constant clearance between two consecutive vehicles at very maintain constant clearance between two consecutive vehicles at very
short gaps (from 3 meters to 10 meters). This platooning can short gaps (from 3 meters to 10 meters). This platooning can
maximize the throughput of vehicular traffic in a highway and reduce maximize the throughput of vehicular traffic in a highway and reduce
the gas consumption because the leading vehicle can help the the gas consumption because the leading vehicle can help the
following vehicles to experience less air resistance. following vehicles to experience less air resistance.
Cooperative-environment-sensing use cases suggest that vehicles can Cooperative-environment-sensing use cases suggest that vehicles can
share environmental information from various vehicle-mounted sensors, share environmental information from various vehicle-mounted sensors,
such as radars, LiDARs and cameras with other vehicles and such as radars, LiDARs, and cameras with other vehicles and
pedestrians. [Automotive-Sensing] introduces a millimeter-wave pedestrians. [Automotive-Sensing] introduces a millimeter-wave
vehicular communication for massive automotive sensing. Data vehicular communication for massive automotive sensing. Data
generated by those sensors can be substantially large, and these data generated by those sensors can be substantially large, and these data
shall be routed to different destinations. In addition, from the shall 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 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 context. interaction with the context.
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.
A navigation service, such as the Self-Adaptive Interactive A navigation service, such as the Self-Adaptive Interactive
Navigation Tool (called SAINT) [SAINT], using V2I networking Navigation Tool (called SAINT) [SAINT], using V2I networking
interacts with TCC for the large-scale/long-range road traffic interacts with TCC for the large-scale/long-range road traffic
optimization and can guide individual vehicles for appropriate optimization and can guide individual vehicles for appropriate
navigation paths in real time. The enhanced version of SAINT navigation paths in real time. The enhanced version of SAINT
[SAINTplus] can give the fast moving paths to emergency vehicles [SAINTplus] can give the fast moving paths to emergency vehicles
(e.g., ambulance and fire engine) to let them reach accident spots (e.g., ambulance and fire engine) to let them reach an accident spot
while providing other vehicles with efficient detour paths. while providing other vehicles near the accident spot with efficient
detour paths.
A TCC can recommend an energy-efficient speed to a vehicle driving in A TCC can recommend an energy-efficient speed to a vehicle driving in
different traffic environments. [Fuel-Efficient] studies fuel- different traffic environments. [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 RSU or 4G-LTE networks.
The First Responder Network Authority (FirstNet) [FirstNet] is The First Responder Network Authority (FirstNet) [FirstNet] is
provided by the US government to establish, operate, and maintain an provided by the US government to establish, operate, and maintain an
interoperable public safety broadband network for safety and security interoperable public safety broadband network for safety and security
network services, such as emergency calls. The construction of the network services, such as emergency calls. The construction of the
nationwide FirstNet network requires each state in the US to have a nationwide FirstNet network requires each state in the US to have a
Radio Access Network (RAN) that will connect to FirstNet's network Radio Access Network (RAN) that will connect to the FirstNet's
core. The current RAN is mainly constructed by 4G-LTE for the network core. The current RAN is mainly constructed by 4G-LTE for
communication between a vehicle and an infrastructure node (i.e., the communication between a vehicle and an infrastructure node (i.e.,
V2I) [FirstNet-Report], but it is expected that DSRC-based vehicular V2I) [FirstNet-Report], but it is expected that DSRC-based vehicular
networks [DSRC] will be available for V2I and V2V in near future. networks [DSRC] will be available for V2I and V2V in near future.
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 (called SANA) [SANA], using V2I2P networking can reduce Application (called SANA) [SANA], using V2I2P networking can reduce
the collision of a vehicle and a pedestrian carrying a smartphone the collision of a vehicle and a pedestrian carrying a smartphone
equipped with the access technology with an RSU (e.g., WiFi). equipped with a network device for wireless communication (e.g.,
Vehicles and pedestrians can also communicate with each other via an WiFi) with an RSU. Vehicles and pedestrians can also communicate
RSU that delivers scheduling information for wireless communication with each other via an RSU that delivers scheduling information for
in order to save the smartphones' battery through sleeping mode. wireless communication in order to save the smartphones' battery
through sleeping mode.
For Vehicle-to-Pedestrian (V2P), a vehicle and a pedestrian's For Vehicle-to-Pedestrian (V2P), a vehicle and a pedestrian's
smartphone can directly communicate with each other via V2X without smartphone can directly communicate with each other via V2X without
the relaying of an RSU as in a V2V scenario such that the the relaying of an RSU as in the V2V scenario that the pedestrian's
pedestrian's smartphone is regarded as a vehicle with a wireless smartphone is regarded as a vehicle with a wireless media interface
media interface to be able to communicate with another vehicle. In to be able to communicate with another vehicle. In Vehicle-to-Device
Vehicle-to-Device (V2D), a device can be a mobile node such as (V2D), a device can be a mobile node such as bicycle and motorcycle,
bicycle and motorcycle, and can communicate directly with a vehicle and can communicate directly with a vehicle for collision avoidance.
for collision avoidance.
4. Analysis for Existing Protocols
4.1. Existing Protocols for Vehicular Networking
We describe some currently existing protocols and proposed solutions
with respect to the following aspects that are relevant and essential
for vehicular networking:
o IP address autoconfiguration;
o Routing protocol;
o Mobility management;
o DNS naming service;
o Service discovery;
o Security and privacy.
4.1.1. IP Address Autoconfiguration
For IP address autoconfiguration, Fazio et al. proposed a vehicular
address configuration (VAC) scheme using DHCP where elected leader-
vehicles provide unique identifiers for IP address configurations in
vehicles [Address-Autoconf]. Kato et al. proposed an IPv6 address
assignment scheme using lane and position information
[Address-Assignment]. Baldessari et al. proposed an IPv6 scalable
address autoconfiguration scheme called GeoSAC for vehicular networks
[GeoSAC]. Wetterwald et al. conducted for heterogeneous vehicular
networks (i.e., employing multiple access technologies) a
comprehensive study of the cross-layer identity management, which
constitutes a fundamental element of the ITS architecture
[Identity-Management].
A server-based address autoconfiguration such as VAC
[Address-Autoconf] takes some delay for a vehicle to join a new
cluster (i.e., a connected VANET) and communicate with neighboring
vehicles. This delay may prevent vehicles from exchaning safety
messages with each other in a prompty way. It will be good for a
vehicle to maintain its IP address even when it joins another
cluster. A geographical-position-based address autoconfiguration,
such as a prefix allocation per lane [Address-Assignment] and a
prefix allocation per geographic region [GeoSAC], causes the frequent
change of a vehicle's IP address and requires the DAD for the
uniqueness test of a new IP address. This is significant overhead
for high-speed moving vehicles. It will be efficient for a vehicle
to be able to use its IP address while moving across the clusters and
geographical regions. For the cross-layer identity management with
multiple wireless interfaces [Identity-Management], it will be
necessary to maintain an upper-layer session (e.g., TCP session) of a
vehicle with multiple IP addresses corresponing to the multiple
wireless interfaces.
4.1.2. Routing Protocol
For vehicular routing, Abboud et al. proposed a cluster-based routing
[Cluster-Based-Routing]. Vehicles construct clusters along with
their location and speed information for fast data dissemination
among the clusters. They consist of cluster headers, cluster
gateways and cluster members for intra-cluster and inter-cluster
communications. Tsukada et al. presented a work that aims at
combining IPv6 networking and a Car-to-Car Network (called C2CNet)
routing protocol proposed by the Car-to-Car Communication Consortium
(C2C-CC). Note that C2CNet is the network layer of the C2C-CC
communication system and uses a geographic routing protocol for
vehicular networks [VANET-Geo-Routing]. Abrougui et al. presented a
gateway discovery scheme for vehicles to access the Internet via a
gateway, called Location-Aided Gateway Advertisement and Discovery
(LAGAD) mechanism [LAGAD]. A vehicle (as a packet source) multihop
away from a gateway can discover the gateway and deliver its packets
to the gateway through the packet forwarding of intermediate vehicles
(as relay vehicles) in a connected VANET. Those intermediate
vehicles are located between the packet source vehicle and the
gateway.
For data packet routing in vehicular networks, multihop V2V and
multihop V2I communications are required. For multihop V2V
communications within a connected VANET, a cluster-based routing like
[Cluster-Based-Routing] can play a role of efficient data forwarding
through a virtual backbone of cluster headers and cluster gateways.
For this, an efficient cluster formation is performed through sharing
the mobility information (e.g., position, direction, and speed) of
vehicles. But the pure VANET-based clustering will cause significant
control messages and need some delay for cluster formation, so
vehicles can perform clustering through infrastructure nodes (e.g.,
RSUs and base stations) via cellular links, which guarantees always-
network-connection.
For multihop V2I communications, a gateway discovery scheme like
LAGAD [LAGAD] can be used through a connected VANET having a
connection with an Internet gateway. However, this reactive gateway
discovery causes much control messages for the discovery and need
some delay until a packet source vehicle can transmit its packets
toward the gateway. Thus, a proactive gateway discovery is required
over a connected VANET where vehicles share routes towards gateways
(e.g., distance vector information to gateways) in a proactive
manner.
4.1.3. Mobility Management
For mobility management, Chen et al. tackled the issue of network
fragmentation in VANET environments [IP-Passing-Protocol] by
proposing a protocol that can postpone the time to release IP
addresses to the DHCP server and select a faster way to get the
vehicle's new IP address, when the vehicle density is low or the
speeds of vehicles are highly variable. Nguyen et al. proposed a
hybrid centralized-distributed mobility management called H-DMM to
support the mobility of high-speed mobile vehicles, which is based on
both DMM and PMIPv6 [H-DMM]. They also proposed a hybrid
centralized-distributed mobility management for network mobility
called H-NEMO to support the efficient mobility of mobile nodes and
mobile routers between different subnets, which is based on both DMM
and PMIPv6 [H-NEMO].
[NEMO-LMS] proposed an architecture to enable IP mobility for moving
networks using a network-based mobility scheme based on PMIPv6. Chen
et al. proposed a network mobility protocol to reduce handoff delay
and maintain Internet connectivity to moving vehicles in a highway
[NEMO-VANET]. Lee et al. proposed P-NEMO, which is a PMIPv6-based IP
mobility management scheme to maintain the Internet connectivity at
the vehicle as a mobile network, and provides a make-before-break
mechanism when vehicles switch to a new access network
[PMIP-NEMO-Analysis]. Peng et al. proposed a novel mobility
management scheme for integration of VANET and fixed IP networks
[VNET-MM]. This scheme uses both a road network layout and the
wireless coverage of multiple base stations in order to improve the
connectivity of vehicles to the Internet and decrease the overhead of
mobility management. Nguyen et al. extended their previous works
(i.e., H-DMM [H-DMM] and H-NEMO [H-NEMO]) on a vehicular DMM by using
a Software-Defined Networking (SDN) architecture, which separates the
control plane and the data plane in network functionality [SDN-DMM].
A vehicle can have an internal network for its in-vehicle devices and
passengers' mobile devices. In this case, vehicular networks need to
support not only the host mobility for the vehicle, but also the
network mobility of such an internet network within the vehicle. The
current mobility management schemes, such as [H-DMM] and [H-NEMO],
are not enough to support both the host mobility and network mobility
in an efficient way. An efficient mobility management scheme can
take advantage of a vehicle's mobility information (e.g., position,
direction, and speed) and partial or full trajectory (i.e., a
navigation path in a road network) in order to perform operations for
mobility management proactively. For this proactive mobility
management, an SDN-based mobility management scheme like [SDN-DMM]
will be promising because SDN controllers can proactively set up
forwarding tables for traffic flows of vehicles with their mobility
and trajectory information.
4.1.4. DNS Naming Service
For DNS naming service, Multicast DNS (mDNS) [RFC6762] allows devices
in one-hop communication range to resolve each other's DNS name into
the corresponding IP address in multicast. DNS Name
Autoconfiguration (DNSNA) [ID-DNSNA] proposes a DNS naming service
for Internet-of-Things (IoT) devices in a large-scale network.
A DNS name resolution service needs to support DNS name resolution
for in-vehicle devices and passengers' mobile devices within a
vehicle's internal network, which can be called intra-vehicle DNS
name resolution. Also, it needs to support DNS name resolution
between devices (e.g., cooperative cruise control device) existing in
different vehicles, which can be called inter-vehicle DNS name
resolution. In addition, it need to support DNS name resolution in
hosts or servers as corresponding nodes in the Internet, which can be
called global DNS name resolution.
For the intra-vehicle DNS name resolution and inter-vehicle DNS name
resolution, both mDNS [RFC6762] and DNSNA [ID-DNSNA] can be used, but
they perform DNS name resolution in a reactive way. That is, when a
DNS query is given by a querier, it will be multicasted to devices
through mDNS or be unicasted to a dedicated DNS server through DNSNA,
respectively.
For the inter-vehicle DNS name resolution in fast-moving vehicles, a
proactive DNS resolution can be performed by the help of an RSU that
collects the DNS information of vehicles and disseminate it to
vehicles under its coverage.
For the global DNS name resolution, a vehicle can use an RSU's DNS
server (or a DNS server close to an RSU in the wired network) to
perform a DNS resolution for the sake of the vehicle's device during
its travel. When the DNS resolution is finished by the RSU's DNS
server, the DNS server can forward the DNS resolution result to the
vehicle through the current RSU providing the vehicle with the
Internet connectivity.
4.1.5. Service Discovery
To discover instances of a demanded service in vehicular networks,
DNS-based Service Discovery (DNS-SD) [RFC6763] with either DNSNA
[ID-DNSNA] or mDNS [RFC6762] provides vehicles with service discovery
by using standard DNS queries. Vehicular ND [ID-Vehicular-ND]
proposes an extension of IPv6 ND for the prefix and service discovery
with new ND options.
For vehicular networks, DNSNA can use a dedicated DNS server residing
in an RSU or close to an RSU in the wired network [ID-DNSNA]. In
this case, in-vehicle devices can register their services (e.g.,
cooperative cruise control service and navigation service) into the
DNS server. When the DNS server can receive a service discovery
query from vehicles via an RSU, it can resolve it quickly for them.
In DNSNA, these DNS query and response messages are delivered in
unicast rather than multicast, so the wireless channel will be
utilized efficiently for DNS resolution including service discovery.
Thus, DNSNA will provide a more efficient service discovery to
vehicles in a high-vehicle-density environment than mDNS [RFC6762]
and Vehicular ND [ID-Vehicular-ND]. This is because a DNS query for
service discovery is unicasted by DNSNA, but it is multicasted by
both mDNS and Vehicular ND.
In a V2V scenario such as the case where a dedicated DNS server in an
RSU is not available for the registration and sharing of service
information, Vehicular ND can provide vehicles with rapid service
discovery by letting vehicles proactively advertise their service
information with Neighbor Advertisement (NA) messages. Thus,
considering both V2I and V2V scenarios, an efficient service
discovery scheme can be designed.
4.1.6. Security and Privacy
For security and privacy, Fernandez et al. proposed a secure
vehicular IPv6 communication scheme using Internet Key Exchange
version 2 (IKEv2) and Internet Protocol Security (IPsec) for
vehiculer networks. This scheme provides the secure communication
channel between a home agent and a mobile router to support the
network mobility of a vehicle's internal network [Securing-VCOMM].
Moustafa et al. proposed a security scheme providing authentication,
authorization, and accounting (AAA) services in vehicular networks
[VNET-AAA]. The vehicular networks consist of VANETs as a front end
and an access network as a back end via an access point. The
security scheme provides vehicles with an efficient AAA service for
the network connectivity during their movement in the road network.
Security services in vehicular networks need to support an efficient
AAA for the accommodation of only valid vehicles and a secure
communication with IKEv2 and IPsec between vehicles or between a
vehicle and the corresponding node in the Internet. For the
efficiency, these security services need to take advantage of a
vehicular network architecture having a TCC and RSUs as well as a
vehicle's mobility and trajectory information.
4.2. General Problems 4. Vehicular Networks
This section describes a possible vehicular network architecture for This section describes a vehicular network architecture supporting
V2V, V2I, and V2X communications. Then it analyzes the limitations V2V, V2I, and V2X communications in vehicular networks. Also, it
of the current protocols for vehicular networking. describes an internal network within a vehicle or RSU, and the
internetworking between the internal networks via DSRC links.
Traffic Control Center in Vehicular Cloud Traffic Control Center in Vehicular Cloud
*-----------------------------------------* *-----------------------------------------*
* * * *
* +----------------+ * * +----------------+ *
* | Mobility Anchor| * * | Mobility Anchor| *
* +----------------+ * * +----------------+ *
* ^ * * ^ *
* | * * | *
*--------------------v--------------------* *--------------------v--------------------*
^ ^ ^ ^ ^ ^
| | | | | |
| | | | | |
v v v v v v
+--------+ Ethernet +--------+ +--------+ +--------+ Ethernet +--------+ +--------+
| RSU1 |<-------->| RSU2 |<---------->| RSU3 | | RSU1 |<-------->| RSU2 |<---------->| 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 +--------+ | | +--------+ |
| | | | | | | | | |
+--------------------------------------+ +------------------+ +-----------------+ +-----------------+ +-----------------+
Subnet1 Subnet2 Subnet1 Subnet2 Subnet3
<----> 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: A Vehicular Network Architecture for V2I and V2V Networking
4.2.1. 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 architecture for V2I and V2V networking in a road
network. As shown in this figure, RSUs as routers and vehicles with network. As shown in this figure, RSUs as routers and vehicles with
OBU have wireless media interfaces for VANET. Also, it is assumed OBU have wireless media interfaces for VANET. Also, it is assumed
that such the wireless media interfaces are autoconfigured with a that such the wireless media interfaces are autoconfigured with a
global IPv6 prefix (e.g., 2001:DB8:1:1::/64) to support both V2V and global IPv6 prefix (e.g., 2001:DB8:1:1::/64) to support both V2V and
V2I networking. V2I networking.
Especially, for IPv6 packets transporting over IEEE 802.11-OCB, Especially, for IPv6 packets transporting over IEEE 802.11-OCB,
[IPv6-over-802.11-OCB] specifies several details, such as Maximum [IPv6-over-802.11-OCB] specifies several details, such as Maximum
skipping to change at page 15, line 17 skipping to change at page 9, line 17
vehicular networks. vehicular networks.
In Figure 1, three RSUs (RSU1, RSU2, and RSU3) are deployed in the In Figure 1, three RSUs (RSU1, RSU2, and RSU3) are deployed in the
road network and are connected to a Vehicular Cloud through the road network and are connected to a Vehicular Cloud through the
Internet. A Traffic Control Center (TCC) is connected to the Internet. A Traffic Control Center (TCC) is connected to the
Vehicular Cloud for the management of RSUs and vehicles in the road Vehicular Cloud for the management of RSUs and vehicles in the road
network. A Mobility Anchor (MA) is located in the TCC as its key network. A Mobility Anchor (MA) is located in the TCC as its key
component for the mobility management of vehicles. Two vehicles component for the mobility management of vehicles. Two vehicles
(Vehicle1 and Vehicle2) are wirelessly connected to RSU1, and one (Vehicle1 and Vehicle2) are wirelessly connected to RSU1, and one
vehicle (Vehicle3) is wirelessly connected to RSU2. The wireless vehicle (Vehicle3) is wirelessly connected to RSU2. The wireless
networks of RSU1 and RSU2 belong to a multi-link subnet (denoted as networks of RSU1 and RSU2 belong to two different subnets (denoted as
Subnet1) with the same network prefix. Thus, these three vehicles Subnet1 and Subnet2), respectively. Also, another vehicle (Vehicle4)
are within the same subnet. On the other hand, another vehicle is wireless connected to RSU3, belonging to another subnet (denoted
(Vehicle4) is wireless connected to RSU4, belonging to another subnet as Subnet3).
(denoted as Subnet2). That is, the first three vehicles (i.e.,
Vehicle1, Vehicle2, and Vehicle3) and the last vehicle (i.e.,
Vehicle4) are located in the two different subnets.
In wireless subnets in vehicular networks (e.g., Subnet 1 and Subnet In wireless subnets in vehicular networks (e.g., Subnet1 and Subnet2
2 in Figure 1), vehicles can construct a connected VANET (as 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 same subnet along their communication because they are within the wireless communication
IPv6 addresses, which are based on the same prefix. On the other range for each other. On the other hand, Vehicle3 can communicate
hand, Vehicle3 can communicate with Vehicle4 via RSU2 and RSU3 with Vehicle4 via the vehicular infrastructure (i.e., RSU2 and RSU3)
employing V2I (i.e., V2I2V) communication because they are within the by employing V2I (i.e., V2I2V) communication because they are not
two different subnets along with their IPv6 addresses, which are within the wireless communication range for each other.
based on the two different prefixes.
In vehicular networks, unidirectional links exist and must be In vehicular networks, unidirectional links exist and must be
considered for wireless communications. Also, in the vehicular considered for wireless communications. Also, in the vehicular
networks, control plane must be separated from data plane for networks, control plane can be separated from data plane for
efficient mobility management and data forwarding using Software- efficient mobility management and data forwarding using Software-
Defined Networking (SDN) [SDN-DMM]. The mobility information of a Defined Networking (SDN) [SDN-DMM]. The mobility information of a
GPS receiver mounted in its vehicle (e.g., trajectory, position, GPS receiver mounted in its vehicle (e.g., trajectory, position,
speed, and direction) can be used for the accommodation of mobility- speed, and direction) can be used for the accommodation of mobility-
aware proactive protocols. Vehicles can use the TCC as their Home aware proactive protocols. Vehicles can use the TCC as their Home
Network having a home agent for mobility management as in MIPv6 Network having a home agent for mobility management as in MIPv6
[RFC6275] and PMIPv6 [RFC5213], so the TCC maintains the mobility [RFC6275] and PMIPv6 [RFC5213], so the TCC maintains the mobility
information of vehicles for location management. Also, IP tunneling information of vehicles for location management. Also, IP tunneling
over the wireless link should be avoided for performance efficiency. over the wireless link should be avoided for performance efficiency.
Cespedes et al. proposed a vehicular IP in WAVE called VIP-WAVE for 4.2. V2I-based Internetworking
I2V and V2I networking [VIP-WAVE]. The standard WAVE does not
support both seamless communications for Internet services and multi-
hop communications between a vehicle and an infrastructure node
(e.g., RSU), either. To overcome these limitations of the standard
WAVE, VIP-WAVE enhances the standard WAVE by the following three
schemes:
1. An efficient mechanism for the IPv6 address assignment and DAD
2. An on-demand IP mobility management based on PMIPv6 [RFC5213]
3. One-hop and two-hop communication scheme for V2I networking
Note that VIP-WAVE supports at most two-hop V2I communication for
simple forwarding operations in VANET. This is because the multi-hop
V2I communication with more than two hops requires an additional
VANET routing protocol. Such a multi-hop V2I communication will be
required for vehicles in a highway with sparsely deployed RSUs in
order to provide them with the Internet connectivity via V2I.
Baccelli et al. provided an analysis of the operation of IPv6 as it
has been described by the IEEE WAVE standards 1609 [IPv6-WAVE]. This
analysis confirms that the use of the standard IPv6 protocol stack in
WAVE is not sufficient. It recommends that the IPv6 addressing
assignment should follow considerations for ad-hoc link models,
defined in [RFC5889] for nodes' mobility and link variability.
However, this ad-hoc link model is not clearly defined to support the
efficient V2V and V2I for vehicles with a wireless interface
configured with an IPv6 address.
Petrescu et al. proposed the joint IP networking and radio
architecture for V2V and V2I communication in [Joint-IP-Networking].
The radio architecture uses Wi-Fi for wireless link rather than IEEE
802.11-OCB. The proposed architecture considers an IP topology in a
similar way as a radio link topology, in the sense that an IP subnet
would correspond to the range of 1-hop vehicular communication. This
architecture defines three types of vehicles: Leaf Vehicle, Range
Extending Vehicle, and Internet Vehicle. Leaf Vehicle is like a
vehicle with OBU and has one external WiFi interface along with an
MR. This MR supports the network mobility of a user's mobile device
and in-vehicle devices in the vehicle's internal network. Range
Extending Vehicles has two external Wi-Fi interfaces to connect two
Wi-Fi subnets of cars in a train. Internet Vehicle has one Wi-Fi
interface for a car's subnet and one Wireless Metropolitan Area
Network (WMAN) interface for the Internet connectivity. However,
this architecture is not suitable for vehicles with a small size and
with a wireless interface for V2V and V2I in vehicular links.
4.2.1.1. V2I-based Internetworking
This section discusses the internetworking between a vehicle's moving This section discusses the internetworking between a vehicle's
network and an RSU's fixed network via V2I communication. internal network (i.e., moving network) and an RSU's internal network
(i.e., fixed network) via V2I communication.
+-----------------+ +-----------------+
(*)<........>(*) +----->| 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 | | DNS1 | |Router1| | | |Router3| | DNS2 | | Host3 | |
| +-------+ +------+ +-------+ | | +-------+ +------+ +-------+ | | +-------+ +------+ +-------+ | | +-------+ +------+ +-------+ |
| ^ ^ ^ | | ^ ^ ^ | | ^ ^ ^ | | ^ ^ ^ |
skipping to change at page 17, line 40 skipping to change at page 10, line 35
| 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) RSU1 (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 Network and RSU Network
Nowadays, a vehicle's internal network tends to be Ethernet to
interconnect electronic control units in a vehicle. It can also
support WiFi and Bluetooth to accommodate a driver's and passenger's
mobile devices (e.g., smartphone and tablet). In this trend, it is
reasonable to consider a vehicle's internal network (i.e., moving
network) and also the interaction between the internal network and an
external network within another vehicle or RSU.
As shown in Figure 2, the vehicle's moving network and the RSU's As shown in Figure 2, the vehicle's moving network and the RSU's
fixed network are self-contained networks having multiple subnets and fixed network are self-contained networks having multiple subnets and
having an edge router for the communication with another vehicle or having an edge router for the communication with another vehicle or
RSU. Internetworking between two internal networks via V2I RSU. Internetworking between two internal networks via V2I
communication requires an exchange of network prefix and other communication requires an exchange of network prefix and other
parameters through a prefix discovery mechanism, such as ND-based parameters through a prefix discovery mechanism, such as ND-based
prefix discovery [ID-Vehicular-ND]. For the ND-based prefix prefix discovery [ID-Vehicular-ND]. For the ND-based prefix
discovery, network prefixs and parameters should be registered into a discovery, network prefixs and parameters should be registered into a
vehicle's router and an RSU router with an external network interface vehicle's router and an RSU router with an external network interface
in advance. in advance.
skipping to change at page 18, line 20 skipping to change at page 11, line 23
information includes the IP address and prefix of an external network information includes the IP address and prefix of an external network
interface for the internetworking with another vehicle or RSU. interface for the internetworking with another vehicle or RSU.
Once the network parameter discovery and prefix exchange operations Once the network parameter discovery and prefix exchange operations
have been performed, packets can be transmitted between the vehicle's have been performed, packets can be transmitted between the vehicle's
moving network and the RSU's fixed network. DNS services should be moving network and the RSU's fixed network. DNS services should be
supported to enable name resolution for hosts or servers residing supported to enable name resolution for hosts or servers residing
either in the vehicle's moving network or the RSU's fixed network. either in the vehicle's moving network or the RSU's fixed network.
It is assumed that the DNS names of in-vehicle devices and their It is assumed that the DNS names of in-vehicle devices and their
service names are registered into a DNS server in a vehicle or an service names are registered into a DNS server in a vehicle or an
RSU, as shown in Figure 2. For service discovery, those DNS names RSU, as shown in Figure 2.
and service names can be advertised to neighboring vehicles through
either DNS-based service discovery mechanisms
[RFC6762][RFC6763][ID-DNSNA] and ND-based service discovery
[ID-Vehicular-ND]. For the ND-based service discovery, service names
should be registered into a vehicle's router and an RSU router with
an external network interface in advance. For this service
discovery, each vehicle and each RSU should have its dedicated DNS
server within its internal network, respectively, as shown in
Figure 2.
Figure 2 shows internetworking between the vehicle's moving network Figure 2 shows internetworking between the vehicle's moving network
and the RSU's fixed network. There exists an internal network and the RSU's fixed network. There exists an internal network
(Moving Network1) inside Vehicle1. Vehicle1 has the DNS Server (Moving Network1) inside Vehicle1. Vehicle1 has the DNS Server
(DNS1), the two hosts (Host1 and Host2), and the two routers (Router1 (DNS1), the two hosts (Host1 and Host2), and the two routers (Router1
and Router2). There exists another internal network (Fixed Network1) and Router2). There exists another internal network (Fixed Network1)
inside RSU1. RSU1 has the DNS Server (DNS2), one host (Host3), the inside RSU1. RSU1 has the DNS Server (DNS2), one host (Host3), the
two routers (Router3 and Router4), and the collection of servers two routers (Router3 and Router4), and the collection of servers
(Server1 to ServerN) for various services in the road networks, such (Server1 to ServerN) for various services in the road networks, such
as the emergency notification and navigation. Vehicle1's Router1 as the emergency notification and navigation. Vehicle1's Router1
(called mobile router) and RSU1's Router3 (called fixed router) use (called mobile router) and RSU1's Router3 (called fixed router) use
2001:DB8:1:1::/64 for an external link (e.g., DSRC) for I2V 2001:DB8:1:1::/64 for an external link (e.g., DSRC) for I2V
networking. networking. Thus, one host (Host1) in Vehicle1 can communicate with
one server (Server1) in RSU1 for a vehicular service through
Vehicle1's moving network, a wireless link between Vehicle1 and RSU1,
and RSU1's fixed network.
4.2.1.2. 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.
(*)<..........>(*) (*)<..........>(*)
2001:DB8:1:1::/64 | | 2001:DB8:1:1::/64 | |
+------------------------------+ +------------------------------+ +------------------------------+ +------------------------------+
| v | | v | | v | | v |
| +-------+ +------+ +-------+ | | +-------+ +------+ +-------+ | | +-------+ +------+ +-------+ | | +-------+ +------+ +-------+ |
| | Host1 | | DNS1 | |Router1| | | |Router5| | DNS3 | | Host4 | | | | Host1 | | DNS1 | |Router1| | | |Router5| | DNS3 | | Host4 | |
skipping to change at page 19, line 43 skipping to change at page 12, line 43
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 the DNS Server (DNS1), the
two hosts (Host1 and Host2), and the two routers (Router1 and two hosts (Host1 and Host2), and the two routers (Router1 and
Router2). There exists another internal network (Moving Network2) Router2). There exists another internal network (Moving Network2)
inside Vehicle2. Vehicle2 has the DNS Server (DNS3), the two hosts inside Vehicle2. Vehicle2 has the DNS Server (DNS3), the two hosts
(Host4 and Host5), and the two routers (Router5 and Router6). (Host4 and Host5), and the two routers (Router5 and Router6).
Vehicle1's Router1 (called mobile router) and Vehicle2's Router5 Vehicle1's Router1 (called mobile router) and Vehicle2's Router5
(called mobile router) use 2001:DB8:1:1::/64 for an external link (called mobile router) use 2001:DB8:1:1::/64 for an external link
(e.g., DSRC) for V2V networking. (e.g., DSRC) for V2V networking. Thus, one host (Host1) in Vehicle1
can communicate with one host (Host4) in Vehicle1 for a vehicular
service through Vehicle1's moving network, a wireless link between
Vehicle1 and Vehicle2, and Vehicle2's moving network.
4.2.2. Latency (*)<..................>(*)<..................>(*)
| | |
+-----------+ +-----------+ +-----------+
| | | | | |
| +-------+ | | +-------+ | | +-------+ |
| |Router1| | | |Router5| | | |Router7| |
| +-------+ | | +-------+ | | +-------+ |
| | | | | |
| +-------+ | | +-------+ | | +-------+ |
| | Host1 | | | | Host4 | | | | Host6 | |
| +-------+ | | +-------+ | | +-------+ |
| | | | | |
+-----------+ +-----------+ +-----------+
Vehicle1 Vehicle2 Vehicle3
The communication delay (i.e., latency) between two vehicles should <....> Wireless Link (*) Antenna
be bounded to a certain threshold (e.g., 500 ms) for collision-
avoidance message exchange [CASD]. For IP-based safety applications
(e.g., context-aware navigation, adaptive cruise control, and
platooning) in vehicular network, this bounded data delivery is
critical. The real implementations for such applications are not
available yet. Thus, the feasibility of IP-based safety applications
is not tested yet in the real world.
4.2.3. Security Figure 4: Multihop Internetworking between Two Vehicle Networks
Strong security measures shall protect vehicles roaming in road Figure 4 shows multihop internetworking between the moving networks
networks from the attacks of malicious nodes, which are controlled by of two vehicles in the same VANET. For example, Host1 in Vehicle1
hackers. For safety applications, the cooperation among vehicles is can communicate with Host6 in Vehicle3 via Router 5 in Vehicle2 that
assumed. Malicious nodes may disseminate wrong driving information is an intermediate vehicle being connected to Vehicle1 and Vehicle3
(e.g., location, speed, and direction) to make driving be unsafe. in a linear topology as shown in the figure.
Sybil attack, which tries to illude 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. Applications on IP-based vehicular networking,
which are resilient to such a sybil attack, are not developed and
tested yet.
4.2.4. Pseudonym Handling 5. Problem Statement
For the protection of drivers' privacy, the pseudonym of a MAC This section makes a problem statement about key topics for IPWAVE
address of a vehicle's network interface should be used, with the WG, such as neighbor discovery, mobility management, and security &
help of which the MAC address can be changed periodically. The privacy.
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
address pair. However, the pseudonym handling is not implemented and
tested yet for applications on IP-based vehicular networking.
5. Problem Exploration 5.1. Neighbor Discovery
This section discusses key topics for IPWAVE WG, such as neighbor IPv6 Neighbor Discovery (IPv6 ND) [RFC4861][RFC4862] is a core part
discovery, mobility management, and security & privacy. of the IPv6 protocol suite. IPv6 ND is designed for point-to-point
links and transit links (e.g., Ethernet). It assumes an efficient
and reliable support of multicast from the link layer for various
network operations such as MAC Address Resolution (AR) and Duplicate
Address Detection (DAD).
5.1. Neighbor Discovery IPv6 ND needs to be extended to vehicular networking (e.g., V2V, V2I,
and V2X) in terms of DAD and ND-related parameters (e.g., Router
Lifetime). The vehicles are moving fast within the communication
coverage of a vehicular node (e.g., vehicle and RSU). Before the
vehicles can exchange application messages with each other, they need
to be configured with a link-local IPv6 address or a global IPv6
address, and recognize each other in the aspect of IPv6 ND.
Neighbor Discovery (ND) [RFC4861] is a core part of the IPv6 protocol The legacy DAD assumes that a node with an IPv6 address can reach any
suite. This section discusses the need for modifying ND for use with other node with the scope of its address at the time it claims its
vehicular networking (e.g., V2V, V2I, and V2X). The vehicles are address, and can hear any future claim for that address by another
moving fast within the communication coverage of a vehicular node party within the scope of its address for the duration of the address
(e.g., vehicle and RSU). The external wireless link between two ownership. However, the partioning and merging of VANETs makes this
vehicular nodes can be used for vehicular networking, as shown in assumption frequently invalid in vehicular networks.
Figure 2 and Figure 3.
The vehicular networks need to support a vehicular-network-wide DAD
by defining a scope that is compatible with the legacy DAD, and two
vehicles can communicate with each other when there exists a
communication path over VANET or a combination of VANETs and RSUs, as
shown in Figure 1. By using the vehicular-network-wide DAD, vehicles
can assure that their IPv6 addresses are unique in the vehicular
network whenever they are connected to the vehicular infrastructure
or become disconnected from it in the form of VANET. Even though a
unique IPv6 address can be derived from a globally unique MAC
address, this derivation yields a privacy issue of a vehicle as an
IPv6 node. The vehicular infrastructure having RSUs and an MA can
participate in the vehicular-network-wide DAD for the sake of
vehicles [RFC6775][RFC8505].
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 should 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.
When ND is used in vehicular networks, the communication delay (i.e.,
latency) between two vehicles should be bounded to a certain
threshold (e.g., 500 ms) for collision-avoidance message exchange
[CASD]. For IP-based safety applications (e.g., context-aware
navigation, adaptive cruise control, and platooning) in vehicular
network, this bounded data delivery is critical. The real
implementations for such applications are not available yet. Thus,
ND needs to appropriately operate to support IP-based safety
applications.
5.1.1. Link Model 5.1.1. Link Model
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]. For do not necessarily hold in a vehicular wireless link [VIP-WAVE]
instance, some IPv6 protocols assume symmetry in the connectivity [RFC5889]. For instance, some IPv6 protocols assume symmetry in the
among neighboring interfaces. However, interference and different connectivity among neighboring interfaces. However, interference and
levels of transmission power may cause unidirectional links to appear different levels of transmission power may cause unidirectional links
in vehicular wireless links. As a result, a new vehicular link model to appear in vehicular wireless links. As a result, a new vehicular
is required for a dynamically changing vehicular wireless link. link model is required for a dynamically changing vehicular wireless
link.
There is a relationship between a link and prefix, besides the There is a relationship between a link and 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 or on-link bit set can communicate with each other on an IP link.
extended IP links via ND proxy. Note that a subnet prefix can be
used by spanning multiple links into a multi-link subnet with an
extended subnet concept [RFC6775]. Also, note that IPv6 Stateless
Address Autoconfiguration (SLAAC) can be performed in the multiple
links where each of them is not assigned with a unique subnet prefix,
that is, all of them are configured with the same subnet prefix
[RFC4861][RFC4862].
A vehicular link model needs to consider a multi-hop V2V (or V2I) A VANET can have multiple links between pairs of vehicles within
over a multi-link subnet as shown in Figure 1. In this figure, wireless communication range, as shown in Figure 4. When two
vehicles in Subnet1 having RSU1 and RSU2 construct a multi-link vehicles belong to the same VANET, but they are out of wireless
subnet called Subnet1 with VANETs and RSUs. Vehicle1 and Vehicle3 communication range, they cannot communicate directly with each
can communicate with each other via multi-hop V2V or multi-hop V2I2V. other. Assume that a global-scope IPv6 prefix is assigned to VANETs
When two vehicles (e.g., Vehicle1 and Vehicle3 in Figure 1) are in vehicular networks. Even though two vehicles in the same VANET
connected in a VANET, they can communicate with each other via VANET configure their IPv6 addresses with the same IPv6 prefix, they may
rather than RSUs. On the other hand, when two vehicles (e.g., not communicate with each other not in a one hop in the same VANET
Vehicle1 and Vehicle3) are far away from the communication range in because of the multihop network connectivity. Thus, in this case,
separate VANETs and under two different RSUs, they can communicate the concept of a on-link IPv6 prefix does not hold because two
with each other through the relay of RSUs via V2I2V. vehicles with the same on-link IPv6 prefix cannot communicate
directly with each other. Also, when two vehicles are located in two
different VANETs with the same IPv6 prefix, they cannot communicate
with each other. When these two VANETs are converged into one VANET,
the two vehicles can communicate with each other in a multihop
fashion. Therefore, a vehicular link model should consider the
frequent partitioning and merging of VANETs due to vehicle mobility.
Thus, IPv6 ND should be extended into a Vehicular Neighbor Discovey An IPv6 prefix can be used in a multi-link subnet as an extended
(VND) [ID-Vehicular-ND] to support the concept of an IPv6 link subnet. IPv6 Stateless Address Autoconfiguration (SLAAC) needs to be
performed even in the multiple links where all of the links are
configured with the same subnet prefix [RFC4861][RFC4862]. Thus, a
vehicular link model can consider a multi-hop V2V (or V2I) over a
multi-link subnet in a vehicular network having multiple VANETs and
RSUs, as shown in Figure 1. For example, in this figure, vehicles
(i.e., Vehicle1, Vehicle2, and Vehicle3) in Subnet1 and Subnet2
having RSU1 and RSU2, respectively, construct a multi-link subnet
with VANETs and RSUs. Vehicle1 and Vehicle3 can also communicate
with each other via either multi-hop V2V or multi-hop V2I2V. When
two vehicles (e.g., Vehicle1 and Vehicle3 in Figure 1) are connected
in a VANET, it will be more efficient for them to communicate with
each other via VANET rather than RSUs. On the other hand, when two
vehicles (e.g., Vehicle1 and Vehicle3) are far away from the
communication range in separate VANETs and under two different RSUs,
they can communicate with each other through the relay of RSUs via
V2I2V.
Therefore, IPv6 ND needs to be extended for an efficient Vehicular
Neighbor Discovey (VND) to support the concept of an IPv6 link
corresponding to an IPv6 prefix even in a multi-link subnet corresponding to an IPv6 prefix even in a multi-link subnet
consisting of multiple vehicles and RSUs that are interconnected with consisting of multiple vehicles and RSUs [ID-Vehicular-ND].
wireless communication range in IP-based vehicular networks.
5.1.2. MAC Address Pseudonym 5.1.2. MAC Address Pseudonym
For the protection of drivers' privacy, the pseudonym of a MAC
address of a vehicle's network interface should be used, with the
help of which the MAC address can be changed periodically. 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
address pair. However, the pseudonym handling is not 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 should be updated, and the uniqueness of the address should be
performed through the DAD procedure. For vehicular networks with performed through the DAD procedure. For vehicular networks with
high-mobility, this DAD should be performed efficiently with minimum high-mobility, this DAD should be performed efficiently with minimum
overhead. overhead.
skipping to change at page 22, line 45 skipping to change at page 17, line 7
vehicular ND (VND) [ID-Vehicular-ND] can support the communication vehicular ND (VND) [ID-Vehicular-ND] can support the communication
between the internal-network nodes (e.g., an in-vehicle device in a between the internal-network nodes (e.g., an in-vehicle device in a
vehicle and a server in an RSU) of vehicular nodes with a vehicular vehicle and a server in an RSU) of vehicular nodes with a vehicular
prefix information option. Thus, this ND extension for routing prefix information option. Thus, this ND extension for routing
functionality can reduce control traffic for routing in vehicular functionality can reduce control traffic for routing in vehicular
networks without a vehicular ad hoc routing protocol (e.g., AODV networks without a vehicular ad hoc routing protocol (e.g., AODV
[RFC3561] and OLSRv2 [RFC7181]). [RFC3561] and OLSRv2 [RFC7181]).
5.1.4. Routing 5.1.4. Routing
For multihop V2V communications in a multi-link subnet (as a For multihop V2V communications in a VANET (or a multi-link subnet),
connected VANET), a vehicular ad hoc routing protocol (e.g., AODV and a vehicular ad hoc routing protocol (e.g., AODV and OLSRv2) may be
OLSRv2) may be required to support both unicast and multicast in the required to support both unicast and multicast in the links of the
links of the subnet with the same IPv6 prefix. Instead of the subnet with the same IPv6 prefix. However, it will be costly to run
vehicular ad hoc routing protocol, Vehicular ND along with a prefix both vehicular ND and a vehicular ad hoc routing protocol in terms of
discovery option can be used to let vehicles exchange their prefixes control traffic overhead. As a feasible approach, Vehicular ND can
in a multihop fashion [ID-Vehicular-ND]. With the exchanged be extended to accommodate routing functionality with a prefix
prefixes, they can compute their routing table (or IPv6 ND's neighbor discovery option. In this case, there is no need to run a separate
cache) for the multi-link subnet with a distance-vector algorithm vehicular ad hoc routing protocol in VANETs. The ND extension can
[Intro-to-Algorithms]. 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 multi-link
subnet with a distance-vector algorithm [Intro-to-Algorithms].
Also, an efficient, rapid DAD should be supported in a multi-link Also, an efficient, rapid DAD needs to be supported in a vehicular
subnet to prevent or reduce IPv6 address conflicts in such a subnet network having multiple VANETs (or a multi-link subnet) to prevent or
by using a multi-hop DAD optimization [ID-Vehicular-ND][RFC6775] or reduce IPv6 address conflicts in such a subnet. A feasible approach
an IPv6 geographic-routing-based address autoconfiguration [GeoSAC]. is to use a multi-hop DAD optimization for the efficient vehicular-
network-wide DAD [RFC6775][RFC8505].
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. The GPS receiver may not provide vehicles with
accurate location information in adverse, local environments such as accurate location information in adverse, local environments such as
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 navigation the assistance from the RSUs or a cellular system with a GPS receiver
system. for location information.
With this GPS navigator, an efficient mobility management is possible With a GPS navigator, an efficient mobility management will be
by vehicles periodically reporting their current position and possible by vehicles periodically reporting their current position
trajectory (i.e., navigation path) to RSUs and a Mobility Anchor (MA) and trajectory (i.e., navigation path) to the vehicular
in TCC. The RSUs and MA can predict the future positions of the infrastructure (having RSUs and an MA in TCC) [ID-Vehicular-MM].
This 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 [ID-Vehicular-ND]. between RSUs along with mobility information.
With the prediction of the vehicle mobility, MA can support RSUs to With the prediction of the vehicle mobility, the vehicular
perform DAD, data packet routing, horizontal handover (i.e., handover infrastructure needs to support RSUs to perform efficient DAD, data
in wireless links using a homogeneous radio technology), and vertical packet routing, horizontal handover (i.e., handover in wireless links
handover (i.e., handover in wireless links using heterogeneous radio using a homogeneous radio technology), and vertical handover (i.e.,
technologies) in a proactive manner. Even though a vehicle moves handover in wireless links using heterogeneous radio technologies) in
into the wireless link under another RSU belonging to a different a proactive manner [ID-Vehicular-MM]. For example, when a vehicle is
subnet, the RSU can proactively perform the DAD for the sake of the moving into the wireless link under another RSU belonging to a
vehicle, reducing IPv6 control traffic overhead in the wireless link different subnet, the RSU can proactively perform the DAD for the
[ID-Vehicular-ND]. To prevent a hacker from impersonating RSUs as sake of the vehicle, reducing IPv6 control traffic overhead in the
bogus RSUs, RSUs and MA should have secure channels via IPsec. 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 Therefore, with a proactive handover and a multihop DAD in vehicular
networks [ID-Vehicular-ND], RSUs can efficiently forward data packets networks, RSUs needs to efficiently forward data packets from the
from the wired network (or the wireless network) to a moving wired network (or the wireless network) to a moving destination
destination vehicle along its trajectory along with the MA. Thus, a vehicle along its trajectory. As a result, a moving vehicle can
moving vehicle can communicate with its corresponding vehicle in the communicate with its corresponding vehicle in the vehicular network
vehicular network or a host/server in the Internet along its or a host/server in the Internet along its trajectory.
trajectory.
5.3. Security and Privacy 5.3. Security and Privacy
Strong security measures shall protect vehicles roaming in road
networks from the attacks of malicious nodes, which are controlled by
hackers. For safety applications, the cooperation among vehicles is
assumed. Malicious nodes may disseminate wrong driving information
(e.g., location, speed, and direction) to make driving be unsafe.
Sybil attack, which tries to illude 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. 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 Security and privacy are paramount in the V2I, V2V, and V2X
networking in vehicular networks. Only authorized vehicles should be networking in vehicular networks. Only authorized vehicles should be
allowed to use vehicular networking. Also, in-vehicle devices and allowed to use vehicular networking. Also, in-vehicle devices and
mobile devices in a vehicle need to communicate with other in-vehicle mobile devices in a vehicle need to communicate with other in-vehicle
devices and mobile devices in another vehicle, and other servers in devices and mobile devices in another vehicle, and other servers in
an RSU in a secure way. an RSU in a secure way.
A Vehicle Identification Number (VIN) and a user certificate along A Vehicle Identification Number (VIN) and a user certificate along
with in-vehicle device's identifier generation can be used to with in-vehicle device's identifier generation can be used to
efficiently authenticate a vehicle or a user through a road efficiently authenticate a vehicle or a user through a road
skipping to change at page 25, line 7 skipping to change at page 19, line 36
This document discussed security and privacy for IP-based vehicular This document discussed security and privacy for IP-based vehicular
networking. networking.
The security and privacy for key components in IP-based vehicular The security and privacy for key components in IP-based vehicular
networking, such as neighbor discovery and mobility management, need networking, such as neighbor discovery and mobility management, need
to be analyzed in depth. to be analyzed in depth.
7. Informative References 7. Informative References
[Address-Assignment]
Kato, T., Kadowaki, K., Koita, T., and K. Sato, "Routing
and Address Assignment using Lane/Position Information in
a Vehicular Ad-hoc Network", IEEE Asia-Pacific Services
Computing Conference, December 2008.
[Address-Autoconf]
Fazio, M., Palazzi, C., Das, S., and M. Gerla, "Automatic
IP Address Configuration in VANETs", ACM International
Workshop on Vehicular Inter-Networking, September 2016.
[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.
[Broadcast-Storm]
Wisitpongphan, N., K. Tonguz, O., S. Parikh, J., Mudalige,
P., Bai, F., and V. Sadekar, "Broadcast Storm Mitigation
Techniques in Vehicular Ad Hoc Networks", IEEE Wireless
Communications, December 2007.
[CA-Cruise-Control] [CA-Cruise-Control]
California Partners for Advanced Transportation Technology California Partners for Advanced Transportation Technology
(PATH), "Cooperative Adaptive Cruise Control", [Online] (PATH), "Cooperative Adaptive Cruise Control", [Online]
Available: Available:
http://www.path.berkeley.edu/research/automated-and- http://www.path.berkeley.edu/research/automated-and-
connected-vehicles/cooperative-adaptive-cruise-control, connected-vehicles/cooperative-adaptive-cruise-control,
2017. 2017.
[CASD] Shen, Y., Jeong, J., Oh, T., and S. Son, "CASD: A [CASD] Shen, Y., Jeong, J., Oh, T., and S. Son, "CASD: A
Framework of Context-Awareness Safety Driving in Vehicular Framework of Context-Awareness Safety Driving in Vehicular
Networks", International Workshop on Device Centric Cloud Networks", International Workshop on Device Centric Cloud
(DC2), March 2016. (DC2), March 2016.
[Cluster-Based-Routing]
Abboud, K. and W. Zhuang, "Impact of Microscopic Vehicle
Mobility on Cluster-Based Routing Overhead in VANETs",
IEEE Transactions on Vehicular Technology, Vol. 64, No.
12, December 2015.
[DSRC] ASTM International, "Standard Specification for [DSRC] ASTM International, "Standard Specification for
Telecommunications and Information Exchange Between Telecommunications and Information Exchange Between
Roadside and Vehicle Systems - 5 GHz Band Dedicated Short Roadside and Vehicle Systems - 5 GHz Band Dedicated Short
Range Communications (DSRC) Medium Access Control (MAC) Range Communications (DSRC) Medium Access Control (MAC)
and Physical Layer (PHY) Specifications", and Physical Layer (PHY) Specifications",
ASTM E2213-03(2010), October 2010. ASTM E2213-03(2010), October 2010.
[ETSI-GeoNetwork-IP] [ETSI-GeoNetwork-IP]
ETSI Technical Committee Intelligent Transport Systems, ETSI Technical Committee Intelligent Transport Systems,
"Intelligent Transport Systems (ITS); Vehicular "Intelligent Transport Systems (ITS); Vehicular
skipping to change at page 27, line 5 skipping to change at page 21, line 11
First Responder Network Authority, "FY 2017: ANNUAL REPORT First Responder Network Authority, "FY 2017: ANNUAL REPORT
TO CONGRESS, Advancing Public Safety Broadband TO CONGRESS, Advancing Public Safety Broadband
Communications", FirstNet FY 2017, December 2017. Communications", FirstNet FY 2017, December 2017.
[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.
[GeoSAC] Baldessari, R., Bernardos, C., and M. Calderon, "GeoSAC - [ID-Vehicular-MM]
Scalable Address Autoconfiguration for VANET Using Jeong, J., Ed., Shen, Y., and Z. Xiang, "Vehicular
Geographic Networking Concepts", IEEE International Mobility Management for IP-Based Vehicular Networks",
Symposium on Personal, Indoor and Mobile Radio draft-jeong-ipwave-vehicular-mobility-management-00 (work
Communications, September 2008. in progress), March 2019.
[H-DMM] Nguyen, T. and C. Bonnet, "A Hybrid Centralized-
Distributed Mobility Management for Supporting Highly
Mobile Users", IEEE International Conference on
Communications, June 2015.
[H-NEMO] Nguyen, T. and C. Bonnet, "A Hybrid Centralized-
Distributed Mobility Management Architecture for Network
Mobility", IEEE International Symposium on A World of
Wireless, Mobile and Multimedia Networks, June 2015.
[ID-DNSNA]
Jeong, J., Ed., Lee, S., and J. Park, "DNS Name
Autoconfiguration for Internet of Things Devices", draft-
jeong-ipwave-iot-dns-autoconf-04 (work in progress),
October 2018.
[ID-Vehicular-ND] [ID-Vehicular-ND]
Jeong, J., Ed., Shen, Y., and Z. Xiang, "IPv6 Neighbor Jeong, J., Ed., Shen, Y., and Z. Xiang, "IPv6 Neighbor
Discovery for IP-Based Vehicular Networks", draft-jeong- Discovery for IP-Based Vehicular Networks", draft-jeong-
ipwave-vehicular-neighbor-discovery-06 (work in progress), ipwave-vehicular-neighbor-discovery-06 (work in progress),
March 2019. March 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
skipping to change at page 28, line 10 skipping to change at page 21, line 45
"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] [Intro-to-Algorithms]
H. Cormen, T., E. Leiserson, C., L. Rivest, R., and C. H. Cormen, T., E. Leiserson, C., L. Rivest, R., and C.
Stein, "Introduction to Algorithms, 3rd ed.", The Stein, "Introduction to Algorithms, 3rd ed.", The
MIT Press, July 2009. MIT Press, July 2009.
[IP-Passing-Protocol]
Chen, Y., Hsu, C., and W. Yi, "An IP Passing Protocol for
Vehicular Ad Hoc Networks with Network Fragmentation",
Elsevier Computers & Mathematics with Applications,
January 2012.
[IPv6-over-802.11-OCB] [IPv6-over-802.11-OCB]
Petrescu, A., Benamar, N., Haerri, J., Lee, J., and T. Benamar, N., Haerri, J., Lee, J., and T. Ernst,
Ernst, "Transmission of IPv6 Packets over IEEE 802.11 "Transmission of IPv6 Packets over IEEE 802.11 Networks
Networks operating in mode Outside the Context of a Basic operating in mode Outside the Context of a Basic Service
Service Set (IPv6-over-80211-OCB)", draft-ietf-ipwave- Set (IPv6-over-80211-OCB)", draft-ietf-ipwave-ipv6-over-
ipv6-over-80211ocb-34 (work in progress), December 2018. 80211ocb-45 (work in progress), April 2019.
[IPv6-WAVE]
Baccelli, E., Clausen, T., and R. Wakikawa, "IPv6
Operation for WAVE - Wireless Access in Vehicular
Environments", IEEE Vehicular Networking Conference,
December 2010.
[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.
[Joint-IP-Networking]
Petrescu, A., Boc, M., and C. Ibars, "Joint IP Networking
and Radio Architecture for Vehicular Networks",
11th International Conference on ITS Telecommunications,
August 2011.
[LAGAD] Abrougui, K., Boukerche, A., and R. Pazzi, "Location-Aided
Gateway Advertisement and Discovery Protocol for VANets",
IEEE Transactions on Vehicular Technology, Vol. 59, No. 8,
October 2010.
[Multicast-802]
Perkins, C., Stanley, D., Kumari, W., and JC. Zuniga,
"Multicast Considerations over IEEE 802 Wireless Media",
draft-perkins-intarea-multicast-ieee802-03 (work in
progress), July 2017.
[Multicast-Alert]
Camara, D., Bonnet, C., Nikaein, N., and M. Wetterwald,
"Multicast and Virtual Road Side Units for Multi
Technology Alert Messages Dissemination", IEEE 8th
International Conference on Mobile Ad-Hoc and Sensor
Systems, October 2011.
[NEMO-LMS]
Soto, I., Bernardos, C., Calderon, M., Banchs, A., and A.
Azcorra, "NEMO-Enabled Localized Mobility Support for
Internet Access in Automotive Scenarios",
IEEE Communications Magazine, May 2009.
[NEMO-VANET]
Chen, Y., Hsu, C., and C. Cheng, "Network Mobility
Protocol for Vehicular Ad Hoc Networks",
Wiley International Journal of Communication Systems,
November 2014.
[PMIP-NEMO-Analysis]
Lee, J., Ernst, T., and N. Chilamkurti, "Performance
Analysis of PMIPv6-Based Network Mobility for Intelligent
Transportation Systems", IEEE Transactions on Vehicular
Technology, January 2012.
[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.
[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,
skipping to change at page 30, line 17 skipping to change at page 22, line 45
[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", [RFC5944] Perkins, C., Ed., "IP Mobility Support in IPv4, Revised",
RFC 5944, November 2010. RFC 5944, November 2010.
[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.
[RFC6762] Cheshire, S. and M. Krochmal, "Multicast DNS", RFC 6762,
February 2013.
[RFC6763] Cheshire, S. and M. Krochmal, "DNS-Based Service
Discovery", RFC 6763, February 2013.
[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.
[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.
[RFC7333] Chan, H., Liu, D., Seite, P., Yokota, H., and J. Korhonen, [RFC7333] Chan, H., Liu, D., Seite, P., Yokota, H., and J. Korhonen,
"Requirements for Distributed Mobility Management", "Requirements for Distributed Mobility Management",
RFC 7333, August 2014. RFC 7333, August 2014.
[RFC7429] Liu, D., Zuniga, JC., Seite, P., Chan, H., and CJ. [RFC7429] Liu, D., Zuniga, JC., Seite, P., Chan, H., and CJ.
Bernardos, "Distributed Mobility Management: Current Bernardos, "Distributed Mobility Management: Current
Practices and Gap Analysis", RFC 7429, January 2015. Practices and Gap Analysis", RFC 7429, January 2015.
[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.
[RFC8505] Thubert, P., Nordmark, E., Chakrabarti, S., and C.
Perkins, "Registration Extensions for IPv6 over Low-Power
Wireless Personal Area Network (6LoWPAN) Neighbor
Discovery", RFC 8505, November 2018.
[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 31, line 22 skipping to change at page 23, line 43
[SANA] Hwang, T. and J. Jeong, "SANA: Safety-Aware Navigation [SANA] Hwang, T. and J. Jeong, "SANA: Safety-Aware Navigation
Application for Pedestrian Protection in Vehicular Application for Pedestrian Protection in Vehicular
Networks", Springer Lecture Notes in Computer Science Networks", Springer Lecture Notes in Computer Science
(LNCS), Vol. 9502, December 2015. (LNCS), Vol. 9502, December 2015.
[SDN-DMM] Nguyen, T., Bonnet, C., and J. Harri, "SDN-based [SDN-DMM] Nguyen, T., Bonnet, C., and J. Harri, "SDN-based
Distributed Mobility Management for 5G Networks", Distributed Mobility Management for 5G Networks",
IEEE Wireless Communications and Networking Conference, IEEE Wireless Communications and Networking Conference,
April 2016. April 2016.
[Securing-VCOMM]
Fernandez, P., Santa, J., Bernal, F., and A. Skarmeta,
"Securing Vehicular IPv6 Communications",
IEEE Transactions on Dependable and Secure Computing,
January 2016.
[TR-22.886-3GPP]
3GPP, "Study on Enhancement of 3GPP Support for 5G V2X
Services", 3GPP TS 22.886, June 2018.
[Truck-Platooning] [Truck-Platooning]
California Partners for Advanced Transportation Technology California Partners for Advanced Transportation Technology
(PATH), "Automated Truck Platooning", [Online] Available: (PATH), "Automated Truck Platooning", [Online] Available:
http://www.path.berkeley.edu/research/automated-and- http://www.path.berkeley.edu/research/automated-and-
connected-vehicles/truck-platooning, 2017. connected-vehicles/truck-platooning, 2017.
[TS-23.285-3GPP] [TS-23.285-3GPP]
3GPP, "Architecture Enhancements for V2X Services", 3GPP 3GPP, "Architecture Enhancements for V2X Services", 3GPP
TS 23.285, June 2018. TS 23.285, June 2018.
[VANET-Geo-Routing]
Tsukada, M., Jemaa, I., Menouar, H., Zhang, W., Goleva,
M., and T. Ernst, "Experimental Evaluation for IPv6 over
VANET Geographic Routing", IEEE International Wireless
Communications and Mobile Computing Conference, June 2010.
[VIP-WAVE] [VIP-WAVE]
Cespedes, S., Lu, N., and X. Shen, "VIP-WAVE: On the Cespedes, S., Lu, N., and X. Shen, "VIP-WAVE: On the
Feasibility of IP Communications in 802.11p Vehicular Feasibility of IP Communications in 802.11p Vehicular
Networks", IEEE Transactions on Intelligent Transportation Networks", IEEE Transactions on Intelligent Transportation
Systems, vol. 14, no. 1, March 2013. Systems, vol. 14, no. 1, March 2013.
[VMaSC-LTE]
Ucar, S., Ergen, S., and O. Ozkasap, "Multihop-Cluster-
Based IEEE 802.11p and LTE Hybrid Architecture for VANET
Safety Message Dissemination", IEEE Transactions on
Vehicular Technology, April 2016.
[VNET-AAA]
Moustafa, H., Bourdon, G., and Y. Gourhant, "Providing
Authentication and Access Control in Vehicular Network
Environment", IFIP TC-11 International Information
Security Conference, May 2006.
[VNET-MM] Peng, Y. and J. Chang, "A Novel Mobility Management Scheme
for Integration of Vehicular Ad Hoc Networks and Fixed IP
Networks", Springer Mobile Networks and Applications,
February 2010.
[WAVE-1609.0] [WAVE-1609.0]
IEEE 1609 Working Group, "IEEE Guide for Wireless Access IEEE 1609 Working Group, "IEEE Guide for Wireless Access
in Vehicular Environments (WAVE) - Architecture", IEEE Std in Vehicular Environments (WAVE) - Architecture", IEEE Std
1609.0-2013, March 2014. 1609.0-2013, March 2014.
[WAVE-1609.2] [WAVE-1609.2]
IEEE 1609 Working Group, "IEEE Standard for Wireless IEEE 1609 Working Group, "IEEE Standard for Wireless
Access in Vehicular Environments - Security Services for Access in Vehicular Environments - Security Services for
Applications and Management Messages", IEEE Std Applications and Management Messages", IEEE Std
1609.2-2016, March 2016. 1609.2-2016, March 2016.
skipping to change at page 33, line 5 skipping to change at page 25, 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. Relevant Topics to IPWAVE Working Group Appendix A. Changes from draft-ietf-ipwave-vehicular-networking-08
This section discusses topics relevant to IPWAVE WG: (i) vehicle
identity management; (ii) multihop V2X; (iii) multicast; (iv) DNS
naming services and service discovery; (v) IPv6 over cellular
networks.
A.1. Vehicle Identity Management
A vehicle can have multiple network interfaces using different access
network technologies [Identity-Management]. These multiple network
interfaces mean multiple identities. To identify a vehicle with
multiple indenties, a Vehicle Identification Number (VIN) can be used
as a globally unique vehicle identifier.
To support the seamless connectivity over the multiple identities, a
cross-layer network architecture is required with vertical handover
functionality [Identity-Management]. Also, an AAA service for
multiple identities should be provided to vehicles in an efficient
way to allow horizontal handover as well as vertical handover; note
that AAA stands for Authentication, Authorization, and Accounting.
A.2. Multihop V2X
Multihop packet forwarding among vehicles in 802.11-OCB mode shows an
unfavorable performance due to the common known broadcast-storm
problem [Broadcast-Storm]. This broadcast-storm problem can be
mitigated by the coordination (or scheduling) of a cluster head in a
connected VANET or an RSU in an intersection area, where the cluster
head can work as a coodinator for the access to wireless channels.
A.3. Multicast
IP multicast in vehicular network environments is especially useful
for various services. For instance, an automobile manufacturer can
multicast a particular group/class/type of vehicles for service
notification. As another example, a vehicle or an RSU can
disseminate alert messages in a particular area [Multicast-Alert].
In general IEEE 802 wireless media, some performance issues about
multicast are found in [Multicast-802]. Since several procedures and
functions based on IPv6 use multicast for control-plane messages,
such as Neighbor Discovery (ND) and Service Discovery,
[Multicast-802] describes that the ND process may fail due to
unreliable wireless link, causing failure of the DAD process. Also,
the Router Advertisement messages can be lost in multicasting.
A.4. DNS Naming Services and Service Discovery
When two vehicular nodes communicate with each other using the DNS
name of the partner node, DNS naming service (i.e., DNS name
resolution) is required. As shown in Figure 2 and Figure 3, a DNS
server within an internal network can perform such DNS name
resolution for the sake of other vehicular nodes.
A service discovery service is required for an application in a
vehicular node to search for another application or server in another
vehicular node, which resides in either the same internal network or
the other internal network. In V2I or V2V networking, as shown in
Figure 2 and Figure 3, such a service discovery service can be
provided by either DNS-based Service Discovery (DNS-SD) [RFC6763]
with mDNS [RFC6762] or the vehicular ND with a new option for service
discovery [ID-Vehicular-ND].
A.5. IPv6 over Cellular Networks
Recently, 3GPP has announced a set of new technical specifications,
such as Release 14 (3GPP-R14) [TS-23.285-3GPP], which proposes an
architecture enhancements for V2X services using the modified
sidelink interface that originally is designed for the LTE-Device-to-
Device (D2D) communications. 3GPP-R14 specifies that the V2X
services only support IPv6 implementation. 3GPP is also
investigating and discussing the evolved V2X services in the next
generation cellular networks, i.e., 5G new radio (5G-NR), for
advanced V2X communications and automated vehicles' applications.
A.5.1. Cellular V2X (C-V2X) Using 4G-LTE
Before 3GPP-R14, some researchers have studied the potential usage of
C-V2X communications. For example, [VMaSC-LTE] explores a multihop
cluster-based hybrid architecture using both DSRC and LTE for safety
message dissemination. Most of the research considers a short
message service for safety instead of IP datagram forwarding. In
other C-V2X research, the standard IPv6 is assumed.
The 3GPP technical specification of [TS-23.285-3GPP] states that both
IP based and non-IP based V2X messages are supported, and only IPv6
is supported for IP based messages. Moreover, [TS-23.285-3GPP]
instructs that a UE autoconfigures a link-local IPv6 address by
following SLAAC in [RFC4862], but without sending Neighbor
Solicitation and Neighbor Advertisement messages for DAD. This is
because a unique prefix is allocated to each node by the 3GPP
network, so the IPv6 addresses cannot be duplicate.
A.5.2. Cellular V2X (C-V2X) Using 5G
The emerging services, functions, and applications, which are
developped in automotive industry, demand reliable and efficient
communication infrastructure for road networks. Correspondingly,
enhanced V2X (eV2X)-based services can be supported by 5G systems.
The 3GPP Technical Report of [TR-22.886-3GPP] is studying new use
cases and the corresponding service requirements for V2X (including
V2V and V2I) using 5G in both infrastructure mode and the sidelink
variations in the future.
Appendix B. Changes from draft-ietf-ipwave-vehicular-networking-07
The following changes are made from draft-ietf-ipwave-vehicular- The following changes are made from draft-ietf-ipwave-vehicular-
networking-07: networking-08:
o This version is revised based on the comments from Charlie Perkins o This version is revised based on the comments from Charlie Perkins
and Sri Gundavelli. and Sri Gundavelli.
o In Section 4.1, the existing protocols relevant to IP vehicular o This version focuses on the problem statement about IP-based
networking are summarized and analyzed with pros and cons. This vehicular networking, such as IPv6 neighbor discovery, mobility
subsection addresses the requirements for IP vehicular networking. management, and security & privacy.
o In Figure 1, a vehicular network architecture is modified to
clarify a multi-link subnet consisting of vehicular wireless
links, and to provide efficient vehicular communications for V2I &
V2V to vehicles whose wireless interface is configured with a
global IP address.
Appendix C. 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 Global Research Laboratory Program This work was supported in part by the MSIT (Ministry of Science and
through the NRF funded by the Ministry of Science and ICT (MSIT) ICT), Korea, under the ITRC (Information Technology Research Center)
(NRF-2013K1A1A2A02078326) and by the DGIST R&D Program of the MSIT support program (IITP-2019-2017-0-01633) supervised by the IITP
(18-EE-01). (Institute for Information & communications Technology Promotion).
This work was supported in part by the French research project This work was supported in part by the French research project
DataTweet (ANR-13-INFR-0008) and in part by the HIGHTS project funded DataTweet (ANR-13-INFR-0008) and in part by the HIGHTS project funded
by the European Commission I (636537-H2020). by the European Commission I (636537-H2020).
Appendix D. 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, and Dirk von Hugo (Deutsche Sri Gundavelli (Cisco), Erik Nordmark, Dirk von Hugo (Deutsche
Telekom). The authors sincerely appreciate their contributions. Telekom), and Pascal Thubert (Cisco). 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
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