< draft-jeong-ipwave-vehicular-neighbor-discovery-06.txt   draft-jeong-ipwave-vehicular-neighbor-discovery-07.txt >
IPWAVE Working Group J. Jeong IPWAVE Working Group J. Jeong
Internet-Draft Y. Shen Internet-Draft Y. Shen
Intended status: Standards Track Z. Xiang Intended status: Standards Track Z. Xiang
Expires: September 12, 2019 Sungkyunkwan University Expires: January 9, 2020 Sungkyunkwan University
March 11, 2019 July 8, 2019
IPv6 Neighbor Discovery for IP-Based Vehicular Networks Vehicular Neighbor Discovery for IP-Based Vehicular Networks
draft-jeong-ipwave-vehicular-neighbor-discovery-06 draft-jeong-ipwave-vehicular-neighbor-discovery-07
Abstract Abstract
This document specifies a Vehicular Neighbor Discovery (VND) as an This document specifies a Vehicular Neighbor Discovery (VND) as an
extension of IPv6 Neighbor Discovery (ND) for IP-based vehicular extension of IPv6 Neighbor Discovery (ND) for IP-based vehicular
networks. An optimized Address Registration and a multihop Duplicate networks. An optimized Address Registration and a multihop Duplicate
Address Detection (DAD) mechanism are performed for having operation Address Detection (DAD) mechanism are performed for having operation
efficiency and also saving both wireless bandwidth and vehicle efficiency and also saving both wireless bandwidth and vehicle
energy. Also, three new ND options for prefix discovery, service energy. Also, three new ND options for prefix discovery, service
discovery, and mobility information report are defined to announce discovery, and mobility information report are defined to announce
the network prefixes and services inside a vehicle (i.e., a vehicle's the network prefixes and services inside a vehicle (i.e., a vehicle's
internal network). Finally, a mobility management scheme is proposed internal network).
for moving vehicles in vehicular environments to support seamless
communication for the continuity of transport-layer sessions (e.g.,
TCP connections).
Status of This Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
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Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
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time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on September 12, 2019. This Internet-Draft will expire on January 9, 2020.
Copyright Notice Copyright Notice
Copyright (c) 2019 IETF Trust and the persons identified as the Copyright (c) 2019 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Requirements Language . . . . . . . . . . . . . . . . . . . . 3 2. Requirements Language . . . . . . . . . . . . . . . . . . . . 3
3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
4. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 4 4. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 4
4.1. Link Model . . . . . . . . . . . . . . . . . . . . . . . 5 4.1. Link Model . . . . . . . . . . . . . . . . . . . . . . . 5
4.2. ND Optimization . . . . . . . . . . . . . . . . . . . . . 6 4.2. ND Optimization . . . . . . . . . . . . . . . . . . . . . 6
4.3. Design Goals . . . . . . . . . . . . . . . . . . . . . . 6 4.3. Design Goals . . . . . . . . . . . . . . . . . . . . . . 6
5. Vehicular Network Architecture . . . . . . . . . . . . . . . 7 5. Vehicular Network Architecture . . . . . . . . . . . . . . . 7
5.1. Vehicular Network . . . . . . . . . . . . . . . . . . . . 7 5.1. Vehicular Network . . . . . . . . . . . . . . . . . . . . 7
5.2. V2I Internetworking . . . . . . . . . . . . . . . . . . . 9 5.2. V2I Internetworking . . . . . . . . . . . . . . . . . . . 9
5.3. V2V Internetworking . . . . . . . . . . . . . . . . . . . 10 5.3. V2V Internetworking . . . . . . . . . . . . . . . . . . . 10
6. ND Extension for Prefix and Service Discovery . . . . . . . . 11 6. ND Extension for Prefix and Service Discovery . . . . . . . . 11
6.1. Vehicular Prefix Information Option . . . . . . . . . . . 11 6.1. Vehicular Prefix Information Option . . . . . . . . . . . 11
6.2. Vehicular Service Information Option . . . . . . . . . . 12 6.2. Vehicular Service Information Option . . . . . . . . . . 12
6.3. Vehicular Mobility Information Option . . . . . . . . . . 13 6.3. Vehicular Mobility Information Option . . . . . . . . . . 13
6.4. Vehicular Neighbor Discovery . . . . . . . . . . . . . . 14 6.4. Vehicular Neighbor Discovery . . . . . . . . . . . . . . 14
6.5. Message Exchange Procedure for V2I Networking . . . . . . 15 6.5. Message Exchange Procedure for V2I Networking . . . . . . 15
7. Address Registration and Duplicate Address Detection . . . . 16 7. Address Registration and Duplicate Address Detection . . . . 16
7.1. Address Autoconfiguration . . . . . . . . . . . . . . . . 17 7.1. Address Autoconfiguration . . . . . . . . . . . . . . . . 17
7.2. Address Registration . . . . . . . . . . . . . . . . . . 17 7.2. Address Registration . . . . . . . . . . . . . . . . . . 17
7.3. Multihop Duplicate Address Detection . . . . . . . . . . 18 7.3. Multihop Duplicate Address Detection . . . . . . . . . . 18
7.4. Pseudonym Handling . . . . . . . . . . . . . . . . . . . 21 7.3.1. DAD without Intermediate Vehicle . . . . . . . . . . 18
8. Mobility Management . . . . . . . . . . . . . . . . . . . . . 21 7.3.2. DAD with one Intermediate Vehicle . . . . . . . . . . 20
9. Security Considerations . . . . . . . . . . . . . . . . . . . 24 7.3.3. DAD with multiple Intermediate Vehicles . . . . . . . 21
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 24 7.4. Pseudonym Handling . . . . . . . . . . . . . . . . . . . 22
10.1. Normative References . . . . . . . . . . . . . . . . . . 24 8. Security Considerations . . . . . . . . . . . . . . . . . . . 22
10.2. Informative References . . . . . . . . . . . . . . . . . 25 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 23
9.1. Normative References . . . . . . . . . . . . . . . . . . 23
9.2. Informative References . . . . . . . . . . . . . . . . . 23
Appendix A. Changes from draft-jeong-ipwave-vehicular-neighbor- Appendix A. Changes from draft-jeong-ipwave-vehicular-neighbor-
discovery-05 . . . . . . . . . . . . . . . . . . . . 27 discovery-06 . . . . . . . . . . . . . . . . . . . . 26
Appendix B. Acknowledgments . . . . . . . . . . . . . . . . . . 27 Appendix B. Acknowledgments . . . . . . . . . . . . . . . . . . 26
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 27 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 26
1. Introduction 1. Introduction
Vehicular Ad Hoc Networks (VANET) have been researched for Vehicular Ad Hoc Networks (VANET) have been researched for
Intelligent Transportation System (ITS) such as driving safety, Intelligent Transportation System (ITS) such as driving safety,
efficient driving and entertainment. Considering the high-speed efficient driving and entertainment. Considering the high-speed
mobility of vehicular network based on Dedicated Short-Range mobility of vehicular network based on Dedicated Short-Range
Communications (DSRC), IEEE 802.11p [IEEE-802.11p] has been Communications (DSRC), IEEE 802.11p [IEEE-802.11p] has been
specialized and was renamed IEEE 802.11 Outside the Context of a specialized and was renamed IEEE 802.11 Outside the Context of a
Basic Service Set (OCB) [IEEE-802.11-OCB] in 2012. IEEE has Basic Service Set (OCB) [IEEE-802.11-OCB] in 2012. IEEE has
standardized Wireless Access in Vehicular Environments (WAVE) standardized Wireless Access in Vehicular Environments (WAVE)
[DSRC-WAVE] standard which is considered as a key component in ITS. [DSRC-WAVE] standard which is considered as a key component in ITS.
The IEEE 1609 standards such as IEEE 1609.0 [WAVE-1609.0], 1609.2 IEEE 1609 standards such as IEEE 1609.0 [WAVE-1609.0], 1609.2
[WAVE-1609.2], 1609.3 [WAVE-1609.3], 1609.4 [WAVE-1609.4] provide a [WAVE-1609.2], 1609.3 [WAVE-1609.3], 1609.4 [WAVE-1609.4] provide a
low-latency and alternative network for vehicular communications. low-latency and alternative network for vehicular communications.
What is more, IP-based vehicular networks specialized as IP Wireless What is more, IP-based vehicular networks specialized as IP Wireless
Access in Vehicular Environments (IPWAVE) [IPWAVE-PS] can enable many Access in Vehicular Environments (IPWAVE) [IPWAVE-PS] can enable many
use cases over vehicle-to-vehicle (V2V), vehicle-to-infrastructure use cases over vehicle-to-vehicle (V2V), vehicle-to-infrastructure
(V2I), and vehicle-to-everything (V2X) communications. (V2I), and vehicle-to-everything (V2X) communications.
VANET features high mobility dynamics, asymmetric and lossy VANET features high mobility dynamics, asymmetric and lossy
connections, and moderate power constraint (e.g., electric cars and connections, and moderate power constraint (e.g., electric cars and
unmanned aerial vehicles). Links among hosts and routers in VANET unmanned aerial vehicles). Links among hosts and routers in VANET
skipping to change at page 3, line 38 skipping to change at page 3, line 31
changing neighbors described in [RFC5889]. IPv6 [RFC8200] is changing neighbors described in [RFC5889]. IPv6 [RFC8200] is
selected as the network-layer protocol for Internet applications by selected as the network-layer protocol for Internet applications by
IEEE 1609.0 and 1609.3. However, the relatively long-time Neighbor IEEE 1609.0 and 1609.3. However, the relatively long-time Neighbor
Discovery (ND) process in IPv6 [RFC4861] is not suitable in VANET Discovery (ND) process in IPv6 [RFC4861] is not suitable in VANET
scenarios. scenarios.
To support the interaction between vehicles or between vehicles and To support the interaction between vehicles or between vehicles and
Rode-Side Units (RSUs), this document specifies a Vehicular Neighbor Rode-Side Units (RSUs), this document specifies a Vehicular Neighbor
Discovery (VND) as an extension of IPv6 ND for IP-based vehicular Discovery (VND) as an extension of IPv6 ND for IP-based vehicular
networks. VND provides vehicles with an optimized Address networks. VND provides vehicles with an optimized Address
Registration, a multihop Duplicate Address Detection (DAD), and an Registration and a multihop Duplicate Address Detection (DAD)
efficient mobility management scheme to support efficient V2V, V2I, mechanism. In addition, an efficient mobility management scheme is
and V2X communications. proposed to support efficient V2V, V2I, and V2X communications.
Detailed statements of the mobility management are addressed in
[I-D.IPWAVE-VMM] .
2. Requirements Language 2. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119]. document are to be interpreted as described in RFC 2119 [RFC2119].
3. Terminology 3. Terminology
This document uses the terminology described in [RFC4861], [RFC4862], This document uses the terminology described in [RFC4861], [RFC4862],
skipping to change at page 4, line 14 skipping to change at page 4, line 11
o WAVE: Acronym for "Wireless Access in Vehicular Environments" o WAVE: Acronym for "Wireless Access in Vehicular Environments"
[WAVE-1609.0]. [WAVE-1609.0].
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., DSRC, Visible Light Communication, 802.15.4, LTE- devices (e.g., DSRC, Visible Light Communication, 802.15.4, LTE-
V2X, etc.) for wireless communications with vehicles and is also V2X, etc.) for wireless communications with vehicles and is also
connected to the Internet as a router or switch for packet connected to the Internet as a router or switch for packet
forwarding. An RSU is typically deployed on the road forwarding. An RSU is typically deployed on the road
infrastructure, either at an intersection or in a road segment, infrastructure, either at an intersection or in a road segment,
but may also be located in car parking area. but may also be located in car parking areas.
o On-Board Unit (OBU): A node that has a DSRC device for wireless o On-Board Unit (OBU): A node that has a DSRC device for wireless
communications with other OBUs and RSUs, and may be connected to communications with other OBUs and RSUs, and may be connected to
in-vehicle devices or networks. An OBU is mounted on a vehicle. in-vehicle devices or networks. An OBU is mounted on a vehicle.
It is assumed that a radio navigation receiver (e.g., Global It is assumed that a radio navigation receiver (e.g., Global
Positioning System (GPS)) is included in a vehicle with an OBU for Positioning System (GPS)) is included in a vehicle with an OBU for
efficient navigation. efficient navigation.
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 the mobility information of vehicles in a road network to support the
address autoconfiguration and mobility management of them. It has address autoconfiguration and mobility management of them. It has
end-to-end connections with RSUs under its control. It maintains end-to-end connections with RSUs under its control. It maintains
a DAD table having the IP addresses of the vehicles moving within a DAD Table recording the IP addresses of vehicles moving within
the communication coverage of its RSUs. the communication coverage of its RSUs.
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. including compute nodes, storage nodes, and network nodes.
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 and has MAs included in a vehicular cloud for vehicular networks and has MAs
under its management. under its management.
4. Overview 4. Overview
This document proposes an optimized ND with a more adaptive structure This document proposes an optimized ND with a more adaptive structure
for vehicular networks considering fast vehicle mobility and wireless for vehicular networks considering fast vehicle mobility and wireless
control traffic overhead related to the legacy ND. Further more, control traffic overhead related to the legacy ND. Furthermore,
prefix and service discovery can be implemented as part of the ND's prefix and service discovery can be implemented as part of the ND's
process along with an efficient Address Registration procedure and process along with an efficient Address Registration procedure and
DAD mechanism for moving vehicles. This document specifies a set of DAD mechanism for moving vehicles. This document specifies a set of
behaviors between vehicles and RSUs to accomplish these goals. behaviors between vehicles and RSUs to accomplish these goals.
4.1. Link Model 4.1. Link Model
There is a relationship between a link and a network prefix along There is a relationship between a link and a network prefix along
with reachability scopes, such as link-local and global scopes. The with reachability scopes, such as link-local and global scopes. The
legacy IPv6 ND protocol [RFC4861] has the following link model. All legacy IPv6 ND protocol [RFC4861] has the following link model. All
IPv6 nodes in the same on-link subnet, which use the same subnet IPv6 nodes in the same on-link subnet, which use the same subnet
prefix with on-link bit set, are reachable with each other by one-hop prefix with the on-link bit set, are reachable with each other by
link. The symmetry of the connectivity among the nodes is preserved, one-hop links. The symmetry of the connectivity among the nodes is
that is, bidirectional connectivity among two on-link nodes. preserved, that is, bidirectional connectivity among two on-link
However, a link model in vehicular networks (called vehicular link nodes. However, a link model in vehicular networks (called vehicular
model) should consider the asymmetry of the connectivity that link model) should consider the asymmetry of the connectivity that
unidirectional links can exist due to interference in wireless unidirectional links can exist due to interference in wireless
channels and the different levels of transmission power in wireless channels and the different levels of transmission power in wireless
network interfaces. network interfaces.
The on-link subnet can be constructed by one link (as a basic service The on-link subnet can be constructed by one link (as a basic service
set) or multiple links (as an extended service set) called a multi- set) or multiple links (as an extended service set) called a multi-
link subnet [RFC6775]. In the legacy multi-link subnet, an all-node- link subnet [RFC6775]. In the legacy multi-link subnet, an all-node-
multicasted packet is copied and related to other links by an ND multicasted packet is copied and related to other links by an ND
proxy. On the other hand, in vehicular networks having fast moving proxy. On the other hand, in vehicular networks having fast moving
vehicles, multiple links can share the same subnet prefix for vehicles, multiple links can share the same subnet prefix for
operation efficiency. For example, if two wireless links under two operation efficiency. For example, if two wireless links under two
adjacent RSUs are in the same subnet, a vehicle as an IPv6 host does adjacent RSUs are in the same subnet, a vehicle as an IPv6 host does
not need to reconfigure its IPv6 address during handover between not need to reconfigure its IPv6 address during handover between
those RSUs. However, the packet relay by an RSU as an ND proxy is those RSUs. However, the packet relay by an RSU as an ND proxy is
not required because such a relay can cause a broadcast storm in the not required because such a relay can cause a broadcast storm in the
extended subnet. Thus, in the multi-link subnet, all-node- extended subnet. Thus, in the multi-link subnet, all-node-
multicasting needs to be well-calibrated to either being confined to multicasting needs to be well-calibrated to either being confined to
multicasting in the current link or being disseminated to other links multicasting in the current link or being disseminated to other links
in the same subnet. in the same subnet.
In a connected multihop VANET, for the efficient communication, In a connected multihop VANET, for efficient communication, vehicles
vehicles in the same link of an RSU can communicate directly with in the same link of an RSU can communicate directly with each other,
each other, not through the serving RSU. This direct wireless not through the serving RSU. This direct wireless communication is
communication is similar to the direct wired communication in an on- similar to the direct wired communication in an on-link subnet using
link subnet using Ethernet as a wired network. The vehicular link Ethernet as a wired network. The vehicular link model needs to
model needs to accommodate both the ad-hoc communication between accommodate both the ad-hoc communication between vehicles and
vehicles and infrastructure communication between a vehicle and an infrastructure communication between a vehicle and an RSU in an
RSU in an efficient and flexible way. Therefore, the IPv6 ND should efficient and flexible way. Therefore, the IPv6 ND should be
be extended to accommodate the concept of a new IPv6 link model in extended to accommodate the concept of a new IPv6 link model in
vehicular networks. vehicular networks.
To support multi-link subnet, this specification employs the Shared- To support multi-link subnet, this specification employs the Shared-
Prefix model for prefix assignments. Shared-Prefix model refer to an Prefix model for prefix assignments. A Shared-Prefix model refers to
addressing model where the prefix(es) are shared by more than one an addressing model where the prefix(es) are shared by more than one
node. In this document, we assume that in a specified subnet, all node. In this document, we assume that in a specified subnet, all
interfaces of RSUs responding for prefix assignments to vehicles hold interfaces of RSUs responding for prefix assignments to vehicles hold
same prefix, which ensure vehicles obtain and maintain same prefix in the same prefix, which ensure vehicles obtain and maintain the same
this subnet scope. prefix in this subnet scope.
4.2. ND Optimization 4.2. ND Optimization
This document takes advantage of the optimized ND for Low-Power This document takes advantage of the optimized ND for Low-Power
Wireless Personal Area Network (6LoWPAN) [RFC6775] because vehicular Wireless Personal Area Network (6LoWPAN) [RFC6775] because vehicular
environments have common parts with 6LoWPAN, such as the reduction of environments have common parts with 6LoWPAN, such as the reduction of
unnecessary wireless traffic by multicasting and the energy saving in unnecessary wireless traffic by multicasting and the energy saving in
battery. Note that vehicles tend to be electric vehicles whose battery. Note that vehicles tend to be electric vehicles whose
energy source is from their battery. energy source is from their battery.
In the optimized IPv6 ND for 6LoWPAN, the connections among nodes are In the optimized IPv6 ND for 6LoWPAN, the connections among nodes are
assumed to be asymmetric and unidirectional because of changing radio assumed to be asymmetric and unidirectional because of changing radio
environment and loss signal. The authors proposed an improved IPv6 environment and loss signal. The authors proposed an optimized IPv6
ND which greatly eliminates link-scope multicast to save energy by ND which greatly eliminates link-scope multicast to save energy by
constructing new options and a new scheme for address configurations. constructing new options and a new scheme for address configurations.
Similarly, this document proposes an improved IPv6 ND by eliminating Similarly, this document proposes an improved IPv6 ND by eliminating
many link-scope-multicast-based ND operations, such as DAD for IPv6 many link-scope-multicast-based ND operations, such as DAD for IPv6
Stateless Address Autoconfiguration (SLAAC) [RFC4862]. Thus, this Stateless Address Autoconfiguration (SLAAC) [RFC4862]. Thus, this
document suggests an extension of IPv6 ND as vehicular ND tailored document suggests an extension of IPv6 ND as vehicular ND tailored
for vehicular networks along with new ND options (e.g., prefix for vehicular networks along with new ND options (e.g., prefix
discovery, service discovery, and mobility information options). discovery, service discovery, and mobility information options).
4.3. Design Goals 4.3. Design Goals
skipping to change at page 6, line 45 skipping to change at page 6, line 45
and remove the necessity for routers to use periodic or and remove the necessity for routers to use periodic or
unsolicited multicast RA to find hosts; unsolicited multicast RA to find hosts;
o To replace Neighbor Unreachable Detection(NUD), create Neighbor o To replace Neighbor Unreachable Detection(NUD), create Neighbor
Cache Entries (NCE) for all registered vehicles in RSUs and MA by Cache Entries (NCE) for all registered vehicles in RSUs and MA by
appending Address Registration Option (ARO) in Neighbor appending Address Registration Option (ARO) in Neighbor
Solicitation (NS), Neighbor Advertisement (NA) messages; Solicitation (NS), Neighbor Advertisement (NA) messages;
o To support a multihop DAD with two new ICMPv6 messages called o To support a multihop DAD with two new ICMPv6 messages called
Duplicate Address Request(DAR) and Duplicate Address Duplicate Address Request(DAR) and Duplicate Address
Confirmation(DAC) to eliminate multicast storm and save energy; Confirmation(DAC) to eliminate multicast storms and save energy;
and
o To support multi-hop communication for vehicles outside the o To support multi-hop communication for vehicles outside the
coverage of RSUs to communicate with the serving RSU via a relay coverage of RSUs to communicate with the serving RSU via a relay
neighbor; and neighbor.
o To provide a mobility management mechanism for seamless
communication during a vehicle's travel in subnets via RSUs.
5. Vehicular Network Architecture 5. Vehicular Network Architecture
This section describes a vehicular network architecture for V2V and This section describes a vehicular network architecture for V2V and
V2I communication. A vehicle and an RSU have their internal networks V2I communication. A vehicle and an RSU have their internal networks
including in-vehicle devices or servers, respectively. including in-vehicle devices or servers, respectively.
5.1. Vehicular Network 5.1. Vehicular Network
A vehicular network architecture for V2I and V2V is illustrated in A vehicular network architecture for V2I and V2V is illustrated in
Figure 1. Three RSUs are deployed along roadside and are connected Figure 1. Three RSUs are deployed along roadsides and are connected
to an MA through wired links. There are two subnets such as Subnet1 to an MA through wired links. There are two subnets such as Subnet1
and Subnet2. The wireless links of RSU1 and RSU2 belong to the same and Subnet2. The wireless links of RSU1 and RSU2 belong to the same
subnet named Subnet1, but the wireless link of RSU3 belongs to subnet named Subnet1, but the wireless link of RSU3 belongs to
another subnet named Subnet2. Vehicle2 is wirelessly connected to another subnet named Subnet2. Vehicle2 is wirelessly connected to
RSU1 while Vehicle3 and Vehicle4 are connected to RSU2 and RSU3, RSU1 while Vehicle3 and Vehicle4 are connected to RSU2 and RSU3,
respectively. Vehicles can directly communicate with each other respectively. Vehicles can directly communicate with each other
through V2V connection (e.g., Vehicle1 and Vehicle2) to share driving through V2V connection (e.g., Vehicle1 and Vehicle2) to share driving
information. In addition, vehicles not in range of any RSU may information. In addition, vehicles not in the range of any RSU may
connect with RSU in multi-hop connection via relay vehicle (e.g., connect with RSU in multi-hop connection via relay vehicle (e.g.,
Vehicle1 can contact RSU1 via Vehicle2). Vehicles are assumed to Vehicle1 can contact RSU1 via Vehicle2). Vehicles are assumed to
start the connection to an RSU when they entered the coverage of the start the connection to an RSU when they entered the coverage of the
RSU. RSU.
The document recommends a multi-link subnet involving multiple RSUs The document recommends a multi-link subnet involving multiple RSUs
as shown in Figure 1. This recommendation aims at the reduction of as shown in Figure 1. This recommendation aims at the reduction of
the frequency with which vehicles have to change their IP address the frequency with which vehicles have to change their IP address
during handover between two adjacent RSUs. To construct this multi- during handover between two adjacent RSUs. To construct this multi-
link subnet, shared-prefix model is proposed. That is, for RSUs in link subnet, a Shared-Prefix model is proposed. That is, for RSUs in
the same subnet, the interfaces responsible for prefix assignment for the same subnet, the interfaces responsible for prefix assignment for
vehicles should hold the same prefix in their global address. This vehicles should hold the same prefix in their global address. This
also promises vehicles achieve same prefix in this scope. When they also promises vehicles achieve the same prefix in this scope. When
pass through RSUs in the same subnet, vehicles do not need to perform they pass through RSUs in the same subnet, vehicles do not need to
the Address Registration and DAD again because they can use their perform the Address Registration and DAD again because they can use
current IP address in the wireless coverage of the next RSU. their current IP address in the wireless coverage of the next RSU.
Moreover, this proposal accord with the assumption that noes Moreover, this proposal accord with the assumption that noes
belonging to the same IP prefix are able to communicate with each belonging to the same IP prefix are able to communicate with each
other directly. On the other hand, if vehicles enter the wireless other directly. On the other hand, if vehicles enter the wireless
coverage of an RSU belonging to another subnet with a different coverage of an RSU belonging to another subnet with a different
prefix, they repeat the Address Registration and DAD procedure to prefix, they repeat the Address Registration and DAD procedure to
update their IP address with the new prefix. update their IP address with the new prefix.
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
<----> 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
In Figure 1, RSU1 and RSU2 are deployed in a multi-link subnet with In Figure 1, RSU1 and RSU2 are deployed in a multi-link subnet with
the same prefix address in their interfaces responding for connection the same prefix address in their interfaces responding for connection
with vehicles. When vehicle2 leaves the coverage of RSU1 and enters with vehicles. When vehicle2 leaves the coverage of RSU1 and enters
RSU2, it maintains its address configuration and ignores Address RSU2, it maintains its address configuration and ignores Address
Registration and DAD steps. If vehicle2 moves into the coverage of Registration and DAD steps. If vehicle2 moves into the coverage of
RSU3, since RSU3 belongs to another subnet and holds a different RSU3, since RSU3 belongs to another subnet and holds a different
prefix from RSU1 and RSU2, so vehicle2 must do Address Registration prefix from RSU1 and RSU2, so vehicle2 must do Address Registration
and DAD just as connecting to a new RSU. Note that vehicles and RSUs and DAD just as connecting to a new RSU. Note that vehicles and RSUs
have their internal networks including in-vehicle devices and have their internal networks including in-vehicle devices and
servers, respectively. The structures of the internal networks are servers, respectively. The structures of the internal networks are
described in [IPWAVE-PS]. described in Section 5.2.
5.2. V2I Internetworking 5.2. V2I Internetworking
This subsection explains V2I internteworking between vehicle network This subsection explains V2I internteworking between a vehicle
and RSU network where vehicle network is an internal network in a network and a RSU network where the vehicle network is an internal
vehicle, and RSU network is an internal network in an RSU, as shown network in a vehicle, and the RSU network is an internal network in
in Figure 2. an RSU, as shown in Figure 2.
+-----------------+ +-----------------+
(*)<........>(*) +----->| Vehicular Cloud | (*)<........>(*) +----->| Vehicular Cloud |
2001:DB8:1:1::/64 | | | +-----------------+ 2001:DB8:1:1::/64 | | | +-----------------+
+------------------------------+ +---------------------------------+ +------------------------------+ +---------------------------------+
| v | | v v | | v | | v v |
| +-------+ +------+ +-------+ | | +-------+ +------+ +-------+ | | +-------+ +------+ +-------+ | | +-------+ +------+ +-------+ |
| | Host1 | |RDNSS1| |Router1| | | |Router3| |RDNSS2| | Host3 | | | | Host1 | |RDNSS1| |Router1| | | |Router3| |RDNSS2| | Host3 | |
| +-------+ +------+ +-------+ | | +-------+ +------+ +-------+ | | +-------+ +------+ +-------+ | | +-------+ +------+ +-------+ |
| ^ ^ ^ | | ^ ^ ^ | | ^ ^ ^ | | ^ ^ ^ |
skipping to change at page 10, line 4 skipping to change at page 10, line 4
internal networks are Moving Network1 and Fixed Network1, internal networks are Moving Network1 and Fixed Network1,
respectively. Vehicle1 has the DNS Server (RDNSS1), the two hosts respectively. Vehicle1 has the DNS Server (RDNSS1), the two hosts
(Host1 and Host2), and the two routers (Router1 and Router2). RSU1 (Host1 and Host2), and the two routers (Router1 and Router2). RSU1
has the DNS Server (RDNSS3), one host (Host5), the two routers has the DNS Server (RDNSS3), one host (Host5), the two routers
(Router5 and Router6). (Router5 and Router6).
It is assumed that RSU1 has a collection of servers (Server1 to It is assumed that RSU1 has a collection of servers (Server1 to
ServerN) for various services in the road networks, such as road ServerN) for various services in the road networks, such as road
emergency notification and navigation services. Vehicle1's Router1 emergency notification and navigation services. Vehicle1's Router1
and RSU1's Router3 use 2001:DB8:1:1::/64 for an external link (e.g., and RSU1's Router3 use 2001:DB8:1:1::/64 for an external link (e.g.,
DSRC) for I2V networking for various vehicular services. The DSRC) for I2V networking for various vehicular services. Vehicular
vehicular applications, such as road emergency notification and applications, such as road emergency notification and navigation
navigation services, can be registered into the DNS Server (i.e., services, can be registered into the DNS Server (i.e., RDNSS) through
RDNSS) through DNSNA protocol in [ID-DNSNA] along with IPv6 ND DNS DNSNA protocol in [ID-DNSNA] along with IPv6 ND DNS options in
options in [RFC8106]. [RFC8106].
Vehicle1's Router1 and RSU1's Router5 can know what vehicular Vehicle1's Router1 and RSU1's Router5 can know what vehicular
applications exist in their internal network by referring to their applications exist in their internal network by referring to their
own RDNSS through the DNSNA protocol [ID-DNSNA]. They can also know own RDNSS through the DNSNA protocol [ID-DNSNA]. They can also know
what network prefixes exist in their internal network through an what network prefixes exist in their internal network through an
intra-domain routing protocoli, such as OSFP. Each vehicle and each intra-domain routing protocol, such as OSFP. Each vehicle and each
RSU announce their network prefixes and services through ND options RSU announce their network prefixes and services through ND options
defined in Section 6. defined in Section 6.
5.3. V2V Internetworking 5.3. V2V Internetworking
This subsection explains V2V internteworking between vehicle This subsection explains V2V internteworking between vehicle
networks, which are internal networks in vehicles, as shown in networks, which are internal networks in vehicles, as shown in
Figure 3. Figure 3.
(*)<..........>(*) (*)<..........>(*)
skipping to change at page 11, line 18 skipping to change at page 11, line 18
Host2), and the two routers (Router1 and Router2). Vehicle2 has the Host2), and the two routers (Router1 and Router2). Vehicle2 has the
DNS Server (RDNSS2), the two hosts (Host3 and Host4), and the two DNS Server (RDNSS2), the two hosts (Host3 and Host4), and the two
routers (Router3 and Router4). routers (Router3 and Router4).
It is assumed that Host1 and Host3 are running a Cooperative Adaptive It is assumed that Host1 and Host3 are running a Cooperative Adaptive
Cruise Control (C-ACC) program for physical collision avoidance. Cruise Control (C-ACC) program for physical collision avoidance.
Also, it is assumed that Host2 and Host4 are running a Cooperative Also, it is assumed that Host2 and Host4 are running a Cooperative
On-board Camera Sharing (C-OCS) program for sharing road hazards or On-board Camera Sharing (C-OCS) program for sharing road hazards or
obstacles to avoid road accidents. Vehicle1's Router1 and Vehicle2's obstacles to avoid road accidents. Vehicle1's Router1 and Vehicle2's
Router3 use 2001:DB8:1:1::/64 for an external link (e.g., DSRC) for Router3 use 2001:DB8:1:1::/64 for an external link (e.g., DSRC) for
V2V networking for various vehicular services. The vehicular V2V networking for various vehicular services. Vehicular
applications, such as C-ACC and C-BCS, can be registered into the DNS applications, such as C-ACC and C-BCS, can be registered into the DNS
Server (i.e., RDNSS) through DNSNA protocol in [ID-DNSNA] along with Server (i.e., RDNSS) through DNSNA protocol in [ID-DNSNA] along with
IPv6 ND DNS options in [RFC8106]. IPv6 ND DNS options in [RFC8106].
Vehicle1's Router1 and Vehicle2's Router3 can know what vehicular Vehicle1's Router1 and Vehicle2's Router3 can know what vehicular
applications exist in their internal network by referring to their applications exist in their internal network by referring to their
own RDNSS through the DNSNA protocol [ID-DNSNA]. They can also know own RDNSS through the DNSNA protocol [ID-DNSNA]. They can also know
what network prefixes exist in their internal network through an what network prefixes exist in their internal network through an
intra-domain routing protocoli, such as OSFP. Each vehicle announces intra-domain routing protocol, such as OSFP. Each vehicle announces
its network prefixes and services through ND options defined in its network prefixes and services through ND options defined in
Section 6. Section 6.
6. ND Extension for Prefix and Service Discovery 6. ND Extension for Prefix and Service Discovery
This section specifies an IPv6 ND extension for vehicle-to-vehicle This section specifies an IPv6 ND extension for vehicle-to-vehicle
(V2V) or vehicle-to-infrastructure (V2I) networking. This section (V2V) or vehicle-to-infrastructure (V2I) networking. This section
also defines three new ND options for prefix discovery, service also defines three new ND options for prefix discovery, service
discovery, and mobility information report: (i) Vehicular Prefix discovery, and mobility information report: (i) Vehicular Prefix
Information (VPI) option, (ii) Vehicular Service Information (VSI) Information (VPI) option, (ii) Vehicular Service Information (VSI)
option, and (iii) Vehicular Mobility Information (VMI) option. It option, and (iii) Vehicular Mobility Information (VMI) option. It
also describes the procedure of the ND protocol with those options. also describes the procedure of the ND protocol with those options.
6.1. Vehicular Prefix Information Option 6.1. Vehicular Prefix Information Option
The VPI option contains IPv6 prefix information in the internal The VPI option contains IPv6 prefix informations in the internal
network. Figure 4 shows the format of the VPI option. network. Figure 4 shows the format of the VPI option.
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Prefix Length | Distance | | Type | Length | Prefix Length | Distance |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved | | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | |
skipping to change at page 13, line 40 skipping to change at page 13, line 40
Protocol 8-bit unsigned integer to indicate the upper-layer Protocol 8-bit unsigned integer to indicate the upper-layer
protocol, such as transport-layer protocol (e.g., protocol, such as transport-layer protocol (e.g.,
TCP, UDP, and SCTP). TCP, UDP, and SCTP).
Reserved2 This field is unused. It MUST be initialized to Reserved2 This field is unused. It MUST be initialized to
zero by the sender and MUST be ignored by the zero by the sender and MUST be ignored by the
receiver. receiver.
Port Number 16-bit unsigned integer to indicate the port number Port Number 16-bit unsigned integer to indicate the port number
for the protocol. for this protocol.
Service Address Service Address
128-bit IPv6 address of a node proving this vehicular 128-bit IPv6 address of a node proving this vehicular
service. service.
6.3. Vehicular Mobility Information Option 6.3. Vehicular Mobility Information Option
The VMI option contains one vehicular mobility information of a The VMI option contains one vehicular mobility information of a
vehicle or an RSU. Figure 6 shows the format of the VMI option. vehicle or an RSU. Figure 6 shows the format of the VMI option.
skipping to change at page 15, line 23 skipping to change at page 15, line 23
messages (e.g., NS and NA) by vehicular ND with VPI and VSI options. messages (e.g., NS and NA) by vehicular ND with VPI and VSI options.
This VND-based discovery eliminates an additional prefix and service This VND-based discovery eliminates an additional prefix and service
discovery scheme, such as DNS-based Service Discovery [RFC6763] discovery scheme, such as DNS-based Service Discovery [RFC6763]
(e.g., Multicast DNS (mDNS) [RFC6762] and DNSNA [ID-DNSNA]), other (e.g., Multicast DNS (mDNS) [RFC6762] and DNSNA [ID-DNSNA]), other
than ND. That is, vehicles and RSUs can rapidly discover the network than ND. That is, vehicles and RSUs can rapidly discover the network
prefixes and services of the other party without any additional prefixes and services of the other party without any additional
service discovery protocol. service discovery protocol.
6.5. Message Exchange Procedure for V2I Networking 6.5. Message Exchange Procedure for V2I Networking
This subsection explains a message exchange procedure for vehicular This subsection explains a message exchange procedure for VND in V2I
neighbor discovery in V2I networking, where a vehicle communicates networking, where a vehicle communicates with its corresponding node
with its correponding node in the Internet via an RSU. in the Internet via an RSU.
Figure 7 shows an example of message exchange procedure in V2I Figure 7 shows an example of message exchange procedure in V2I
networking. Detailed steps of the procedure are explained in networking. Detailed steps of the procedure are explained in
Section 7 and Section 8. Section 7. The mobility management part is described in
[I-D.IPWAVE-VMM].
Note that a vehicle could also perform the prefix and service Note that a vehicle could also perform the prefix and service
discovery simultaneously along with Address Registration procedure, discovery simultaneously along with Address Registration procedure,
as shown in Figure 9. as shown in Figure 9.
This document specified that RSUs as routers do not transmit This document specified that RSUs as routers do not transmit
periodical and unsolicited multicast RA messages including a prefix periodical and unsolicited multicast RA messages including a prefix
for energy saving in vehicular networks. Vehicles as hosts for energy saving in vehicular networks. Vehicles as hosts
periodically initiate an RS message according to a time interval periodically initiate an RS message according to a time interval
(considering its position and an RSU's coverage). Since they have a (considering its position and an RSU's coverage). Since they have a
digital road map with the information of RSUs (e.g., position and digital road map with the information of RSUs (e.g., position and
communication coverage), vehicles can know when they will go out of communication coverage), vehicles can know when they will go out of
the communication range of an RSU along with the signal strength the communication range of an RSU along with the signal strength
(e.g., Received Channel Power Indicator (RCPI) [VIP-WAVE]) from the (e.g., Received Channel Power Indicator (RCPI) [VIP-WAVE]) from the
RSU. RSUs replies with a solicited RA in unicast only when they RSU. RSUs replies with a solicited RA in unicast only when they
receive an RS message. receive an RS message.
Vehicle RSU Mobility Anchor Vehicle RSU MA
| | | | | |
|-RS with Mobility Info->| | |-RS with Mobility Info->| |
| [VMI] | | | [VMI] | |
| | | | | |
| |--------PBU------>| | |--------PBU------>|
| | | | | |
| | | | | |
| |<-------PBA-------| | |<-------PBA-------|
| | | | | |
| | | | | |
skipping to change at page 17, line 19 skipping to change at page 17, line 19
2. Vehicle has already configured its IP addresses with prefix 2. Vehicle has already configured its IP addresses with prefix
obtained from the previous RSU, and the current RSU located in obtained from the previous RSU, and the current RSU located in
the same subnet: This means RSUs have the same prefix and the the same subnet: This means RSUs have the same prefix and the
vehicle has no need to repeat the Address Registration and vehicle has no need to repeat the Address Registration and
multihop DAD. multihop DAD.
3. Vehicle is not in the coverage of RSU but has a neighbor 3. Vehicle is not in the coverage of RSU but has a neighbor
registered in RSU: This document proposes a new V2V scenario for registered in RSU: This document proposes a new V2V scenario for
vehicles which are currently not in the range of the RSU. If a vehicles which are currently not in the range of the RSU. If a
user vehicle failed to find an on-link RSU, it starts to look for user vehicle failed to find an on-link RSU, it starts to look for
adjacent vehicle neighbors which can work as relay neighbor to adjacent vehicle neighbors which can work as a relay neighbor to
share the prefix obtained from RSU and undertake the DAD of the share the prefix obtained from RSU and undertake DAD of the user
user vehicle by forwarding DAD messages to RSU. vehicle by forwarding DAD messages to RSU.
7.1. Address Autoconfiguration 7.1. Address Autoconfiguration
A vehicle as an IPv6 host creates its link-local IPv6 address and A vehicle as an IPv6 host creates its link-local IPv6 address and
global IPv6 address as follows [RFC4862]. When they receive RS global IPv6 address as follows [RFC4862]. When they receive RS
messages from vehicles, RSUs send back RA messages containing prefix messages from vehicles, RSUs send back RA messages containing prefix
information. The vehicle makes its global IPv6 addresses by information. The vehicle makes its global IPv6 addresses by
combining the prefix for its current link and its link-layer address. combining the prefix for its current link and its link-layer address.
The address autoconfiguration does not perform the legacy DAD as The address autoconfiguration does not perform the legacy DAD as
skipping to change at page 19, line 5 skipping to change at page 18, line 42
With the multihop DAD, a vehicle can skip the multicast-based DAD in With the multihop DAD, a vehicle can skip the multicast-based DAD in
its current wireless link whenever it enters the coverage of another its current wireless link whenever it enters the coverage of another
RSU in the same subset, leading to the reduction of traffic overhead RSU in the same subset, leading to the reduction of traffic overhead
in vehicular wireless links. in vehicular wireless links.
For the multihop DAD, two new ICMPv6 message types are defined in For the multihop DAD, two new ICMPv6 message types are defined in
[RFC6775], such as Duplicate Address Request (DAR) and the Duplicate [RFC6775], such as Duplicate Address Request (DAR) and the Duplicate
Address Confirmation (DAC). Information carried by ARO options are Address Confirmation (DAC). Information carried by ARO options are
copied into these two messages for the multihop DAD in the MA. copied into these two messages for the multihop DAD in the MA.
Vehicle RSU Mobility Anchor 7.3.1. DAD without Intermediate Vehicle
Figure 9 presents the procedure of Address Registration and multihop
DAD. The detailed steps are explained as follows.
Vehicle RSU MA
| | | | | |
| | | | | |
1. |--NS with Address Reg-->| | 1. |--NS with Address Reg-->| |
| [ARO+VPI+VSI] | | | [ARO+VPI+VSI] | |
| | | | | |
| | | | | |
2. | | -------DAR------>| 2. | | -------DAR------>|
| | | | | |
| | | | | |
3. | |<-------DAC-------| 3. | |<-------DAC-------|
| | | | | |
| | | | | |
| | | | | |
4. |<--NA with Address Reg--| | 4. |<--NA with Address Reg--| |
| [ARO+VPI+VSI] | | | [ARO+VPI+VSI] | |
Figure 9: Neighbor Discovery Address Registration with Multihop DAD Figure 9: Neighbor Discovery Address Registration with Multihop DAD
Figure 9 presents the procedure of Address Registration and multihop
DAD. The detailed steps are explained as follows.
1. A vehicle sends an NS message to the current RSU in unicast, 1. A vehicle sends an NS message to the current RSU in unicast,
containing the ARO to RSU to register its address. containing the ARO to RSU to register its address.
2. The RSU receives the NS message, and then inspects its Neighbor 2. The RSU receives the NS message, and then inspects its Neighbor
Cache to check whether it is duplicate or not. If there is no Cache to check whether it is duplicate or not. If there is no
duplicate NCE, a tentative NCE is created for this address, and duplicate NCE, a tentative NCE is created for this address, and
then the RSU sends a DAR to the MA for the multicast DAD. then the RSU sends DAR to the MA for the multihop DAD.
3. When the MA receives a DAR from an RSU, it checks whether the 3. When the MA receives DAR from an RSU, it checks whether the
register-requested address exists in its DAD Table or not. If an register-requested address exists in its DAD Table or not. If an
entry with the same address exists in the DAD Table, which means entry with the same address exists in the DAD Table, which means
that the address is considered "Duplicate Address", then MA that the address is considered "Duplicate Address", then MA
returns a DAC message to notify the RSU of the address returns a DAC message to notify the RSU of the address
duplication. If no entry with the same address exists in the DAD duplication. If no entry with the same address exists in the DAD
Table, which means that an entry for the address is created, then Table, which means that an entry for the address is created, then
MA replies a DAC message to the RSU to confirm the uniqueness of MA replies a DAC message to the RSU to confirm the uniqueness of
the register-requested address to the RSU. the register-requested address to the RSU.
4. If the address duplication is notified by the MA, the RSU deletes 4. If the address duplication is notified by the MA, the RSU deletes
skipping to change at page 20, line 10 skipping to change at page 20, line 7
registration vehicle to notify the registration failure. registration vehicle to notify the registration failure.
Otherwise, the RSU changes the tentative NCE into a registered Otherwise, the RSU changes the tentative NCE into a registered
NCE in its Neighbor Cache, and then send back an NS to the NCE in its Neighbor Cache, and then send back an NS to the
vehicle to notify the registration success. vehicle to notify the registration success.
Thus, the multihop DAD is processed simultaneously with the Address Thus, the multihop DAD is processed simultaneously with the Address
Registration. Note that the tentative address is not considered Registration. Note that the tentative address is not considered
assigned to the vehicle until the MA confirms the uniqueness of the assigned to the vehicle until the MA confirms the uniqueness of the
register-requested address in the multihop DAD. register-requested address in the multihop DAD.
User Vehicle Relay Vehicle RSU Mobility Anchor 7.3.2. DAD with one Intermediate Vehicle
| | | |
|------------------------| | |
| RD failed | | |
|------------------------| | |
| | | |
| | | |
|-----------NS---------->| | |
| | | |
|<--NA with Prefix Info--| | |
| | | |
| | | |
|--NS with Address Reg-->| | |
| [ARO+VPI+VSI] | | |
| |----- Forward NS ----->| |
| | | |
| | |-----------------|
| | | Same as Figure 9|
| | |-----------------|
| | | |
| |<--NA with Address Reg-| |
| | [ARO+VPI+VSI] | |
|<------ Forward NA -----| | |
| | | |
Figure 10: Address Registration and Multihop DAD via V2V Relay
If a vehicle failed to register a default router, it triggers If a vehicle failed to register a default router, it triggers
neighbor discovery to look for vehicle neighbors which can provide neighbor discovery to look for vehicle neighbors which can provide
relay service using multi-hop communication. In this specification, relay service using multi-hop communication. In this specification,
we assumed vehicles would not emulate V2V communication and trigger we assumed vehicles would not emulate V2V communication and trigger
relay scenario only if Router Discovery(RD) failed. On the other relay scenario only if Router Discovery(RD) failed.
hand, at most one intermediate vehicle acts as a relay for another
vehicle to communicate with the RSU. User Vehicle Relay Vehicle RSU MA
| | | |
|------------------------| | |
| RD failed | | |
|------------------------| | |
| | | |
| | | |
|-----------NS---------->| | |
| | | |
|<--NA with Prefix Info--| | |
| | | |
| | | |
|--NS with Address Reg-->| | |
| [ARO+VPI+VSI] | | |
| |----- Forward NS ----->| |
| | | |
| | |-----------------|
| | | Same as Figure 9|
| | |-----------------|
| | | |
| |<--NA with Address Reg-| |
| | [ARO+VPI+VSI] | |
|<------ Forward NA -----| | |
| | | |
Figure 10: Address Registration and Multihop DAD via V2V Relay
Since vehicles have a digital road map with the information of RSUs Since vehicles have a digital road map with the information of RSUs
(e.g., position and communication coverage), they can determine if (e.g., position and communication coverage), they can determine if
they are available to serve as relay vehicle. Only vehicles with they are available to serve as a relay vehicle. Only vehicles with
ability to serve as temporary relays will take action when they the ability to serve as temporary relays will take action when they
receive relay service requests. The user vehicle can process global receive relay service requests. The user vehicle can process global
address configuration, Address Registration and DAD through relay address configuration, Address Registration and DAD through its relay
vehicle before it enters the coverage of RSUs. See Figure 10. vehicle before it enters the coverage of RSUs. See Figure 10.
When a user vehicle failed to directly register with a RSU, it When a user vehicle failed to directly register to an RSU, it
initiates neighbor discovery to detect vehicle neighbors through V2V initiates neighbor discovery to detect vehicle neighbors through V2V
communication. Vehicle sends NS messages to connect with neighbors communication. Vehicle sends NS messages to connect with neighbors
in range. If neighbor can provide relay service, it creates a NCE in range. If neighbor can provide relay service, it creates a NCE
for user vehicle, setting its own address as relay address, and sends for user vehicle, setting its own address as relay address, and sends
back NA with prefix information received from RSU. back NA with prefix information received from RSU.
To guarantee vehicles could find the nearest neighbor from multiple
neighbors which can act as relay vehicles, a new time-out mechanism
is presented to select the nearest neighbor by hop distance parameter
carried in Prefix Information Option. That is, a user vehicle
multicast NS messages to look for relay vehicles after RD failed and
wait for 1.5 seconds to receive all NA replies from neighbors. Each
NA carries its own global prefix(es) and the hop distance(s) in
Prefix Information Option. The user vehicle preserves every NA reply
in a temporary router list and select the one with least hop counts
as its relay vehicle after time out.
With receipt of NA, user vehicle configures its global address with With receipt of NA, user vehicle configures its global address with
prefix information as mentioned in Section 7.1. After this, user prefix information as mentioned in Section 7.1. After this, user
vehicle takes up to initiate the Address Registration along with DAD vehicle takes up to initiate the Address Registration along with DAD
process via relay vehicle. NS message is configured as specified in process via relay vehicle. NS message is configured as specified in
Section 7.2 but indicate the relay vehicle's address as next-hop for Section 7.2 but indicate the relay vehicle's address as next-hop to
reaching the RSU. In such a case, when relay vehicle receives relay reach the RSU. In such a case, when relay vehicle receives relay
request message, it will forward NS message to RSU. The procedure request message, it will forward NS message to RSU. The procedure
set up on the rails except MA will include the relay vehicle's set up on the rails except MA will include the relay vehicle's
address as relay address in NCE to indicate that at this moment it is address as relay address in NCE to indicate that at this moment, it
not a directly attached vehicle, and set the relay address as next- is not a directly attached vehicle, and set the relay address as
hop address. Relay vehicle forwards DAD result information message next-hop address. Relay vehicle forwards DAD result information
to user vehicle as soon as it received. message to user vehicle as soon as it received.
7.3.3. DAD with multiple Intermediate Vehicles
This document supports multihop communications (e.g., multihop DAD
and UDP transmission) for remote vehicles through multiple relay
vehicles. Vehicles which have already finished DAD process can serve
as temporary routers and forward packets for remote vehicles.
A new routing mechanism is specified to accomplish route selections
among user vehicles and serving RSUs when multiple vehicles act as
relay vehicles. Taking advantage of the Destination-Sequenced
Distance-Vector routing protocol (DSDV) [DSDV], this new routing
approach supposes that each vehicle holds a Neighbor Routing
Table which integrates the neighbor information in Neighbor Cache and
forwarding records for remote vehicles. Each vehicle which acts as a
relay vehicle for this remote vehicle will make records in its
Neighbor Routing Table.
Figure 11 specifies an example of parameters in Neighbor Routing
Table when more than one vehicle work as intermediate relay vehicles.
In Figure 11, Vehicle3 connects RSU1 indirectly via Vehicle2 and
Vehicle3. When Vehicle2 and Vehicle3 forward messages for Vehicle1,
they make records in its Neighbor Routing Table including the next-
hop node to indicate the route to Vehicle3. This can ensure that the
packete from a source vehicle can be successfully transmitted to an
RSU as well as the reverse packet path exists from the RSU to the
source vehicle.
+--------+ +--------+ +--------+ +--------+
|Vehicle3|<......>|Vehicle2|<........>|Vehicle1|<.......> | RSU1 |
| (V3) | V2V | (V2) | V2V | (V1) | V2I | |
+--------+ +--------+ +--------+ +--------+
+------------+ +------------+ +------------+ +------------+
|Node|NextHop| |Node|NextHop| |Node|NextHop| |Node|NextHop|
+------------+ +------------+ +------------+ +------------+
| V2 | V2 | | V1 | V1 | |RSU1| RSU1 | | V1 | V1 |
+------------+ | V3 | V3 | | V2 | V2 | | V2 | V1 |
+------------+ | V3 | V2 | | V3 | V1 |
+------------+ +------------+
Figure 11: An Exmaple of Neighbor Routing Table when multiple
Vehicles act as Relay Vehicles
7.4. Pseudonym Handling 7.4. Pseudonym Handling
Considering the privacy protection of a vehicle, a pseudonym Considering the privacy protection of a vehicle, a pseudonym
mechanism for its link-layer address is requested. This mechanism mechanism for its link-layer address is requested. This mechanism
periodically modifies the link-layer address, leading to the update periodically modifies the link-layer address, leading to the update
of the corresponding IP address. A random MAC Address Generation of the corresponding IP address. A random MAC Address Generation
mechanism is proposed in Appendix F.4 of [IEEE-802.11-OCB] by mechanism is proposed in Appendix F.4 of [IEEE-802.11-OCB] by
generating the 46 remaining bits of MAC address using a random number generating the 46 remaining bits of MAC address using a random number
generator. When it changes its MAC address, a vehicle should ask the generator. When it changes its MAC address, a vehicle should ask the
serving RSU to update its own NCE, and to register its IP address serving RSU to update its own NCE, and to register its IP address
into the MA again. into the MA again.
8. Mobility Management 8. Security Considerations
A mobility management is required for the seamless communication of
vehicles moving between the RSUs. When a vehicle moves into the
coverage of another RSU, a different IP address is assigned to the
vehicle, resulting in the reconfiguration of transport-layer session
information (i.e., end-point IP address) to avoid service disruption.
Considering this issue, this document proposes a handover mechanism
for seamless communication.
Vehicle RSU Mobility Anchor
| | |
|-RS with Mobility Info->| |
| [VMI] | |
| | |
| |--------PBU------>|
| | |
| | |
| |<-------PBA-------|
| | |
| | |
| |===Bi-Dir Tunnel==|
| | |
| | |
|<----RA with prefix-----| |
| | |
Figure 11: Message Interaction for Vehicle Attachment
In [VIP-WAVE], the authors constructed a network-based mobility
management scheme using Proxy Mobile IPv6 (PMIPv6) [RFC5213], which
is highly suitable to vehicular networks. This document uses a
mobility management procedure similar to PMIPv6 along with prefix
discovery.
Figure 11 shows the binding update flow when a vehicle entered the
subnet of an RSU. RSUs act as Mobility Anchor Gateway (MAG) defined
in [VIP-WAVE]. When it receives RS messages from a vehicle
containing its mobility information (e.g., position, speed, and
direction), an RSU sends its MA a Proxy Binding Update (PBU) message
[RFC5213][RFC3775], which contains a Mobility Option for the
vehicle's mobility information. The MA receives the PBU and sets up
a Binding Cache Entry (BCE) as well as a bi-directional tunnel
(denoted as Bi-Dir Tunnel in Figure 11) between the serving RSU and
itself. Through this tunnel, all traffic packets to the vehicle are
encapsulated toward the RSU. Simultaneously, the MA sends back a
Proxy Binding Acknowledgment (PBA) message to the serving RSU. This
serving RSU receives the PBA and sets up a bi-directional tunnel with
the MA. After this binding update, the RSU sends back an RA message
to the vehicle including its own prefix for the address
autoconfiguration.
Vehicle c-RSU Mobility Anchor n-RSU
| | | |
| |===Bi-Dir Tunnel==| |
| | | |
| | | |
| |----DeReg PBU---->| |
| | | |
| | | |
| |<-------PBA-------| |
| | | |
| | | |
| | | |
| | | |
| | | |
|---------------------------RS-------------------------->|
| |
| Registration step as shown in Figure 5 |
| |
| | |===Bi-Dir Tunnel==|
| |
|<--------------------------RA---------------------------|
| |
Figure 12: Message Interaction for Vehicle Handoff
When the vehicle changes its location, the MA has to change the end-
point of the tunnel for the vehicle into the new RSU's IP address.
As shown in Figure 12, when the MA receives a new PBU from the new
RSU, it changes the tunnel's end-point from the current RSU (c-RSU)
to the new RSU (n-RSU). If there is ongoing IP packets toward the
vehicle, the MA encapsulates the packets and then forwards them
towards n-RSU. Through this network-based mobility management, the
vehicle is not aware of any changes at its network layer and can
maintain its transport-layer sessions without any disruption.
If c-RSU and n-RSU are adjacent, that is, vehicles are moving in
specified routes with fixed RSU allocation, the procedure can be
simplified by constructing bidirectional tunnel directly between them
(cancel the intervention of MA) to alleviate the traffic flow in MA
as well as reduce handover delay. See Figure 13.
Vehicle c-RSU n-RSU
| | |
|---------------------| |
|c-RSU detects leaving| |
|---------------------| |
| |--------PBU------>|
| | |
| |===Bi-Dir Tunnel==|
| | |
| |<-------PBA-------|
| | |
| | |
|(-------------------RS---------------->)|
| |
| |
|<-------------------RA------------------|
| |
Figure 13: Vehicle Handoff between Adjacent RSUs
Since RSUs are in charge of detecting when a node joins or moves
through its domain, if c-RSU detects the vehicle is going to leave
its coverage and enter the area of adjacent RSU, it sends a PBU
message to inform n-RSU about the handover of vehicle and update its
mobility information. n-RSU receives the request and construct a
bidirectional tunnel between c-RSU and itself, then send back PBA
message for acknowledgment. If there are ongoing IP packets, c-RSU
encapsulates the packets and then forwards them to n-RSU. When n-RSU
detects the entrance of the vehicle, it directly sends RA mesage to
vehicle for connection establishment (or replies solicited RA if
vehicle sends request RS message first).
9. Security Considerations
This document shares all the security issues of the neighbor This document shares all the security issues of the neighbor
discovery protocol and 6LoWPAN protocol. This document can get discovery protocol and 6LoWPAN protocol. This document can get
benefits from secure neighbor discovery (SEND) [RFC3971] in order to benefits from secure neighbor discovery (SEND) [RFC3971] in order to
protect ND from possible security attacks. protect ND from possible security attacks.
10. References 9. References
10.1. Normative References 9.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997. Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC3775] Johnson, D., Perkins, C., and J. Arkko, "Mobility Support
in IPv6", RFC 3775, June 2004.
[RFC3971] Arkko, J., "SEcure Neighbor Discovery (SEND)", RFC 3971, [RFC3971] Arkko, J., "SEcure Neighbor Discovery (SEND)", RFC 3971,
March 2005. March 2005.
[RFC4861] Narten, T., Nordmark, E., Simpson, W., and H. Soliman, [RFC4861] Narten, T., Nordmark, E., Simpson, W., and H. Soliman,
"Neighbor Discovery for IP Version 6 (IPv6)", RFC 4861, "Neighbor Discovery for IP Version 6 (IPv6)", RFC 4861,
September 2007. September 2007.
[RFC4862] Thomson, S., Narten, T., and T. Jinmei, "IPv6 Stateless [RFC4862] Thomson, S., Narten, T., and T. Jinmei, "IPv6 Stateless
Address Autoconfiguration", RFC 4862, September 2007. Address Autoconfiguration", RFC 4862, September 2007.
[RFC5213] Gundavelli, S., Leung, K., Devarapalli, V., and K.
Chowdhury, "Proxy Mobile IPv6", RFC 5213, August 2008.
[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.
[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., Ed., "Neighbor Discovery Optimization for IPv6 [RFC6775] Shelby, Z., Ed., "Neighbor Discovery Optimization for IPv6
over Low-Power Wireless Personal Area Networks over Low-Power Wireless Personal Area Networks
(6LoWPANs)", RFC 6775, November 2012. (6LoWPANs)", RFC 6775, November 2012.
[RFC8106] Jeong, J., Park, S., Beloeil, L., and S. Madanapalli, [RFC8106] Jeong, J., Park, S., Beloeil, L., and S. Madanapalli,
"IPv6 Router Advertisement Options for DNS Configuration", "IPv6 Router Advertisement Options for DNS Configuration",
RFC 8106, March 2017. RFC 8106, March 2017.
[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.
10.2. Informative References 9.2. Informative References
[DSDV] Perkins, C. and P. Bhagwat, "Highly Dynamic Destination-
Sequenced Distance-Vector Routing (DSDV) for Mobile
Computers", ACM SIGCOMM, August 1994.
[DSRC-WAVE] [DSRC-WAVE]
Morgan, Y., "Notes on DSRC & WAVE Standards Suite: Its Morgan, Y., "Notes on DSRC & WAVE Standards Suite: Its
Architecture, Design, and Characteristics", Architecture, Design, and Characteristics",
IEEE Communications Surveys & Tutorials, 12(4), 2012. IEEE Communications Surveys & Tutorials, 12(4), 2012.
[I-D.IPWAVE-VMM]
Jeong, J., Ed., Shen, Y., and Z. Xiang, "Vehicular
Mobility Management for IP-Based Vehicular Networks",
draft-jeong-ipwave-vehicular-mobility-management-01 (work
in progress), July 2019.
[ID-DNSNA] [ID-DNSNA]
Jeong, J., Ed., Lee, S., and J. Park, "DNS Name Jeong, J., Ed., Lee, S., and J. Park, "DNS Name
Autoconfiguration for Internet of Things Devices", draft- Autoconfiguration for Internet of Things Devices", draft-
jeong-ipwave-iot-dns-autoconf-05 (work in progress), March jeong-ipwave-iot-dns-autoconf-06 (work in progress), July
2019. 2019.
[IEEE-802.11-OCB] [IEEE-802.11-OCB]
"Part 11: Wireless LAN Medium Access Control (MAC) and "Part 11: Wireless LAN Medium Access Control (MAC) and
Physical Layer (PHY) Specifications", IEEE Std Physical Layer (PHY) Specifications", IEEE Std
802.11-2016, December 2016. 802.11-2016, December 2016.
[IEEE-802.11p] [IEEE-802.11p]
"Part 11: Wireless LAN Medium Access Control (MAC) and "Part 11: Wireless LAN Medium Access Control (MAC) and
Physical Layer (PHY) Specifications Amendment 6: Wireless Physical Layer (PHY) Specifications Amendment 6: Wireless
Access in Vehicular Environments", June 2010. Access in Vehicular Environments", June 2010.
[IPWAVE-PS] [IPWAVE-PS]
Jeong, J., Ed., "IP Wireless Access in Vehicular Jeong, J., Ed., "IP Wireless Access in Vehicular
Environments (IPWAVE): Problem Statement and Use Cases", Environments (IPWAVE): Problem Statement and Use Cases",
draft-ietf-ipwave-vehicular-networking-08 (work in draft-ietf-ipwave-vehicular-networking-09 (work in
progress), March 2019. progress), May 2019.
[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.
[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.
[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
skipping to change at page 27, line 6 skipping to change at page 26, line 6
IEEE 1609 Working Group, "IEEE Standard for Wireless IEEE 1609 Working Group, "IEEE Standard for Wireless
Access in Vehicular Environments (WAVE) - Networking Access in Vehicular Environments (WAVE) - Networking
Services", IEEE Std 1609.3-2016, April 2016. Services", IEEE Std 1609.3-2016, April 2016.
[WAVE-1609.4] [WAVE-1609.4]
IEEE 1609 Working Group, "IEEE Standard for Wireless IEEE 1609 Working Group, "IEEE Standard for Wireless
Access in Vehicular Environments (WAVE) - Multi-Channel Access in Vehicular Environments (WAVE) - Multi-Channel
Operation", IEEE Std 1609.4-2016, March 2016. Operation", IEEE Std 1609.4-2016, March 2016.
Appendix A. Changes from draft-jeong-ipwave-vehicular-neighbor- Appendix A. Changes from draft-jeong-ipwave-vehicular-neighbor-
discovery-05 discovery-06
The following changes are made from draft-jeong-ipwave-vehicular- The following changes are made from draft-jeong-ipwave-vehicular-
neighbor-discovery-05: neighbor-discovery-06:
o In Section 4.1, a Shared-Prefix model is introduced for prefix
assignment specified in this document.
o In Section 4.3, design goals are refined including the o The Mobility Management Section is removed and moved to
cancellation of Neighbor Unreachable Detection, and also the [I-D.IPWAVE-VMM].
support of multi-hop communication for vehicles not in the
coverage of RSUs.
o In Section 5.1, the Vehicular Network Architecture is updated on o In Section 7.3, an arbitrary number of intermediate vehicles can
subnet division and V2V communication. be used between source vehicles and RSUs for the address
registration along with multihop DAD.
o In Section 7, a new scenario is added to facilitate vehicles o In Section 7.3.2, a new waiting mechanism is defined to guarantee
outside the coverage of RSU to do Address Registration and DAD via vehicles to find a neighbor vehicle (as a relay node) closest to
relay vehicle. an RSU in order to connect to the RSU.
o In Section 8, a simplified mobility management in vehicle handoff o In Section 7.3.3, a new routing mechanism is proposed to extend
for adjacent RSUs is supplemented based on the original proposal. the IPv6 neighbor discovery protocol for routing among vehicles
and RSUs. An example of Neighbor Routing Table is specialized to
explain the routing service.
Appendix B. Acknowledgments Appendix B. Acknowledgments
This work was supported by Basic Science Research Program through the This work was supported by Basic Science Research Program through the
National Research Foundation of Korea (NRF) funded by the Ministry of National Research Foundation of Korea (NRF) funded by the Ministry of
Education (2017R1D1A1B03035885). Education (2017R1D1A1B03035885).
This work was supported in part by Global Research Laboratory Program This work was supported by the MSIT (Ministry of Science and ICT),
through the NRF funded by the Ministry of Science and ICT (MSIT) 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).
Authors' Addresses Authors' Addresses
Jaehoon Paul Jeong Jaehoon Paul Jeong
Department of Software Department of Computer Science and Engineering
Sungkyunkwan University Sungkyunkwan University
2066 Seobu-Ro, Jangan-Gu 2066 Seobu-Ro, Jangan-Gu
Suwon, Gyeonggi-Do 16419 Suwon, Gyeonggi-Do 16419
Republic of Korea Republic of Korea
Phone: +82 31 299 4957 Phone: +82 31 299 4957
Fax: +82 31 290 7996 Fax: +82 31 290 7996
EMail: pauljeong@skku.edu EMail: pauljeong@skku.edu
URI: http://iotlab.skku.edu/people-jaehoon-jeong.php URI: http://iotlab.skku.edu/people-jaehoon-jeong.php
Yiwen Chris Shen Yiwen Chris Shen
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