This PowerPoint covers VANET in general and illustrates its Components, standards, applications,Types of communications Fleet Management Systems, Routing protocols, Challenges, and the deployment of VANET in Real Scenarios

1. Sarah Hasan – Iman Saeed
Vehicular Ad Hoc Network
VANET

2. Outline
• General Introduction about VANET
• Components of VANET
• Human-machine interface
• Automation levels
• Types of communications
▫ V to V communication
▫ V to I communication
▫ I to I communication
• VANET standards
• VANET applications
▫ Safety Applications
▫ Intelligent transport applications
▫ Comfort applications
• Fleet Management Systems
• Routing protocols
• Challenges
▫ Technical Challenges
▫ Social and Economic Challenges
• Deployment of VANET in Real Scenarios
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3. General information about
VANET
• VANET “Vehicular Ad Hoc Network” is an application of
MANET & self-configuring network of Vehicles.
• Nodes are connected by wireless links
• Vehicles are free to move in all directions “360-degree”
• Communications requires above standard wireless to
handle the fast dynamic network changes and to provide real-
time results with high accuracy such as IEEE802.11P
• Every node sends, receives, and retransmits data that includes
speed, location, and direction.
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4. General information about
VANET
• VANET has some unique properties like:
▫ Dynamic topologies
▫ Infinite energy supply
▫ Road pattern restriction
▫ Scalable network size
▫ Predefined directions
▫ The topology change in an in-deterministic
▫ There is variation in the vehicle density
(Less in Highway & dense in city)
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5. Components of VANET
• Vehicles
• Electronic and hardware components like sensors and actuators, also
software components like operating systems, diagnostics software,
peripheral drivers and so on.
• Intelligent Actuators are five separate main units of the vehicle
(Engine, Transmission, Suspension, Brake system and Steering system )
• Integrated Vehicle Control which has an influence on the movement of
the whole vehicle.
• Sensor devices
(Radar, Video Camera, and Lidar “static laser Scanner, in 1 direction”)
• Road side Unites.
• Control of Vehicle Groups and Fleets
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6. Human-machine machine
interface
• HMI is not only a communication bridge between the driver and
the car itself, but is also an important connector between the driver
and outside world.
• Requirements
▫ Readability
▫ Clarity
▫ Interpretability
▫ Accessibility
▫ Ease of handling
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7. Human-machine machine
interface-Cont’
• Visual interfaces.
• Voice feedback.
• Vibration.
• Mechanical interfaces.
▫ Press by hand, finger or foot.
▫ Pull, slide or rotate by hand.
▫ Touch by hand or finger.
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8. Automation levels
• Warning
• Support
• Semi-automated
• Highly automated
• Full Automation
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9. Automation levels
Warning
▫ It uses the interface of the vehicle to provide information for the driver then it’s up to the
driver to take actions.
Support
▫ Hints will be provided to direct the driver to do the right manoeuvre.
Semi-automated intervention
▫ Vehicle is able to monitor and understand the traffic ahead.
▫ Vehicle can adjust the speed and keep safe distance automatically.
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10. Automation levels
Highly automated intervention
▫ Temporary Auto Pilot, is an automated support for Roadwork and Congestion.
▫ Automatically adjust speed to better maintain inter-vehicle distance, enable
acceleration, braking for the vehicle, and lane changing.
▫ The driver can take back the vehicle control anytime in safety-critical situations
and the vehicle can give back control to the driver if the preconditions are not
met.
Full Automation
▫ There are some promising experiments on fully automated manoeuvring of
vehicles but most of them are focus on a different areas and are far from being
able to adapt on public roads without an intelligent, independent road
infrastructure.
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11. 11

12. • Vehicular To Vehicular (V2V)
• Vehicular To Infrastructure (V2I)
• Infrastructure To Infrastructure (I2I)
Vehicular Communications
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13. V2V
Communication
• Communications between vehicles in ad hoc mode
• A vehicle can receive, transmit or exchange valuable traffic
information such as traffic conditions and road accidents with
other vehicles
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14. V2I Communication
• Broadcast between the network infrastructure and vehicles
• Exchange of useful information about road conditions and
safety measures to be taken into account
• A vehicle establishes a connection with the RSU to connect
and communicate with external networks such as the Internet
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15. 15

16. Vanet Network
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17. VANET Standards
▫ IEEE 802.11p standard
 A Dedicated Short Range Communication (DSRC) is proposed which is operating on 5.9GHz band
and uses 802.11 access methods
 provides short range communication with low latency.
 add wireless access in vehicular environments (V2V, I2V Communications)
▫ IEEE 1609 standard
 family of standards that function in the middle layers of the protocol stack to flexibly support
safety applications in VANETs .
▫ J2735 standard
 placed in the application layer
 It defines message sets, data frames and elements which are used for V2V and V2I safety
exchanges
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18. VANET Standards
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19. VENET applications
• Safety Applications.
• Intelligent transport applications .
• Comfort applications.
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20. Safety Applications
• Safety Applications enhances the driving conditions and reduces the
chances of accidents by providing enough time to the driver and
applying the brakes automatically. These can be further divide into
the following:
▫ Cooperative collision warning .
▫ Incident management.
▫ Emergency video streaming .
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21. Intelligent transport applications
• These applications focus on observing the traffic pattern and
managing accordingly. It provides faster delivery of traffic
information, and improves the efficiency and accuracy of traffic
detection. It can be further categorized into the following:
▫ Traffic Monitoring
▫ Traffic Management
▫ Platooning
▫ Vehicle tracking
▫ Notification services
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22. Comfort applications
• Comfort applications are the applications that relates to comfort
level of the passenger in the vehicle. It can be further categorized
into the following:
▫ Parking place management.
▫ Distributed games and/or talks.
▫ Peer to Peer applications
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23. 23

24. Fleet Management System
• Collects, store and provide complete comprehensive
information about the current state of the vehicles and
cargo, the route history, the expected events, as well as
the driver activities for the vehicle maintenance and
operator companies.
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25. • Cost reduction
▫ decrease in the overall operating costs of the company
 Ex: improve the quality of the estimation of the fuel norm through the measurement of the real consumption
 Ex: provides the possibility of the maximal utilization of the vehicle parts’ lifetime by the complex monitoring of
the vehicle , it warns for the necessity of the replacement and supports the logistics solutions also.
• Logistics management
▫ The possibility of on-line vehicle tracking is an ideal tool for the optimization of the logistic processes
• Vehicle categories
▫ In early FMS (large goods vehicle) , collected only the GPS positions and sent it by SMS to the central server
▫ With the reduction of costs , it is used in all vehicle segments
 Large goods vehicle (commercial vehicles over 3.5 tons)
 light commercial vehicles (commercial vehicles not more than 3.5 tons)
 passenger vehicles
 construction and agricultural machinery
FMS General Requirements in
Transportation
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26. • Data acquisition and Data handling
• Data transmission
▫ Two Categories of FMS : depending on the data location
 off-line : If there is a recording unit in the vehicle and the recorded data are
processed and evaluated afterwards
 on-line : if all the vehicles are connected on-line to a computer server over mobile
internet, and real-time information and data evaluation is available
• Identification tasks of motor vehicle
▫ Ex: use the “natural” identifier of the GSM unit called IMEI number
which can be connected to the vehicle’s license plate or the vehicle
identity number (VIN) in the central server’s relational database.
FMS System Functions
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27. • Alerts
▫ enable the system to indicate abnormal operations to the driver
and to the system center also
• Positioning
▫ Determining the vehicle’s location
FMS System Functions-Cont’
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28. • On-board units , central server, user computers.
Architecture of Fleet Management
Systems
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29. On-board units (OBU)
• The on-board unit is made up of the following main
units:
GSM/GPS module
central unit
human interface device
diagnostic adapter
I/O module
power supply unit and background batteries
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30. GPS /GSM Unit : AVL (Automatic Vehicle Locator ) or commonly called vehicle
tracking device
sends the positioning information on-line to a central computer server.
AVL devices may be extended with vehicle technical information like fuel
tank level, engine revolution, fuel used, and so on.
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31. OBU - Data Acquisition
• The most important and most complex function of the on-board
unit is the exact acquisition of the vehicle data with special regard
to the fuel consumption
• There are two ways to collect the necessary data:
▫ sensor retrofit
 used generally because of the low penetration and hard reachability of the in-vehicle
communication buses.
 Drawbacks:
 high cost, low reliability and accuracy, safety and warranty problems .
▫ in-vehicle communication buses
 generally based on the CAN bus technology
 developed for automotive applications but later - due to its simplicity, reliability and
electromagnetic immunity - it appeared also in industrial (CANopen), military
(MilCAN), aerospace (CANaerospace) and nautical (SeaCAN) applications.
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32. OBU - Communication
• In on-line fleet management systems, the data have to be transferred with
high reliability and integrity.
• At present the fleet management systems use the public GSM network for
data transmission.
• There are three possible technologies for this task:
▫ SMS based
▫ circuit-switched
▫ packet-switched (used most frequently)
 Ex: The most widespread is the GPRS (General Packet Radio Service), and EGPRS
(Enhanced GPRS) which ensures larger bandwidth. In the 3G networks the UMTS
and HSDPA can be used, but these techniques haven’t come into general use in fleet
management systems because of the low covering and high prices of the devices.
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33. OBU - Communication
• The advantages of the packet switched technologies are the
following:
▫ continuous connection
▫ larger bandwidth
▫ data amount based costs
▫ low prices
• The SMS based data transmission can be a backup in case of GPRS
service’s unavailability and it can be used for special purposes, for
example sending alerts directly to mobile phones.
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34. Communication System
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35. Central system
• The central system based on a server system which
consists of several databases and application servers.
• It has to deal with the following tasks:
▫ data receiving
▫ data checks (syntactic, semantic, checksum)
▫ data conversion and passing to the database
▫ acknowledging to the clients
▫ identification of the drivers
▫ sending the parameters of the OBU
▫ software update.
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36. The communication server connects to a database system
which contains three main databases:
1. transactional database
2. data warehouse
3. map database.
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37. User System
• User system consists of the user computers which
are connected to the server system and the user
software.
• A Fleet Management System can include many user
functions:
▫ Vehicle maintenance
▫ Vehicle tracking and diagnostic
▫ Fuel management
▫ Driver management
▫ Tachograph management (Remote download)
▫ Health and safety management
• Basically the user system should display the geographical data of the
vehicles on a map and the base vehicle data with easy filtering and
ordering possibilities.
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38. Network Architectures
Pure Cellular/WLAN-Pure ad hoc-Hybrid
• VANETs can combine both 3G cellular and WLAN
depending on the availability to form a network.
• Vehicles and road-side wireless devices form a pure
mobile ad hoc network to perform V2V communications
• Hybrid architecture combines network infrastructure
and ad hoc networks together in order to allow
communication through multi-hop links to remain
connected.
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39. Routing protocols
• VANETs routing protocols classified into five classes based on the routing protocols
characteristics and techniques:
▫ Topology based routing protocol
▫ Position based routing protocol
▫ Geo-cast routing protocol
▫ Cluster based routing protocol
▫ Broadcast routing protocol.
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40. Topology Based Routing
Protocols
• TBRP uses network links to collect information
and perform packet forwarding. They are further
divided into:
▫ Proactive routing protocols.
▫ Reactive routing protocols.
▫ Hyper routing protocols.
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41. Topology Based Routing
Protocols-Cont’
• Proactive routing protocols
▫ Routes to destinations will always be available when needed in a routing
table
▫ Each entry in the table contains the next hop node in the route to the
destination.
▫ The table updated and broadcasted frequently to reflect the network
topology changes.
▫ This may cause more overhead especially in the high mobility network.
▫ There are various types of proactive routing protocols such as: OLSR, FSR
and DSDV.
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42. Topology Based Routing
Protocols-Cont’
• Reactive routing Protocols
▫ RRPs are suitable for the large size of the mobile ad hoc networks.
▫ RRPs reduce network overhead as it opens the route only when it is
necessary.
▫ How it works? The source node starts a route discovery process when
it needs, by flooding the network with a route request message
▫ When message reaches to the destination a reply message will be
sent back to the source node with actual path.
▫ There are various types of reactive routing protocols such as: AODV,
DSR, TORA and JARR.
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43. Topology Based Routing
Protocols-Cont’
• Hybrid Routing Protocols
▫ HRP combines both proactive and reactive protocols.
▫ It minimize the:
 Overhead control in Proactive Routing protocols.
 Route discovery delay process in Reactive Routing Protocol.
▫ Each node in HRP divides the network into two regions:
(Inside and Outside regions)
▫ HRP uses a proactive routing mechanism to maintain routes to inside region
nodes
▫ HRP uses a route discovery mechanism to reach the outside region nodes.
▫ There are various types of HRP s such as: ZRP, HARP, GPSR and HAODV.
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44. Position Based Routing
Protocols
• PBRP is based on the positional information.
▫ Each node uses (GPS) to locate its position, the position of its neighbours
and the position of the destination.
• Position of the destination is stored in the packet’s header to forward the
packet without needs to:
(Route discovery, Route maintenance, Awareness of the network topology)
• There are 2 types of PBRPs greedy V2V protocols and Delay Tolerant
Protocols.
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45. Position Based Routing
Protocols-Cont’
1) Position Based Greedy V2V Protocols
▫ In greedy strategy, the route is forwarded to nodes that are
constantly closest to the destination
▫ If no neighbouring node close to the destination, perimeter
forwarding will be used to decide to which node it will deliver the
packet
▫ Greedy Perimeter Stateless Routing (GPSR) keeps information of
its first neighbour's positions, to increase protocol scalability and
improve dynamic forwarding.
▫ GPSR could face a link failure due to the high mobility and frequent
topology changes as it holds information of the old position.
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46. Position Based Routing
Protocols-Cont’
1) Position Based Greedy V2V Protocols -Cont’
▫ Greedy Perimeter Coordinator Routing (GPCR) spreads the
packet all over the road until it reaches the next intersection.
▫ If no coordinator node was found in the route, the packet will be
forwarded to furthest node.
▫ If density is low, delay might be increased.
▫ Hybrid Position-Based Routing reduces control routing overhead.
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47. Position Based Routing
Protocols-Cont’
2) Delay Tolerant Protocols
▫ DTN is suitable for networks with issues like:
(Frequent disconnection, Large scale, Long unavoidable delays)
(Limited bandwidth and High bit fault rates)
▫ In this protocol, all nodes do store and forward packet
▫ If the intermediate nodes have a limited transmission range, the packets
transmission will be delayed also.
▫ DTN protocol does not guarantee end to end connectivity.
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48. • Geo-cast routing “GRP” is basically a location based multicast routing.
• GRPs aim to deliver the packet from source node to a group of destinations
in a network.
• GRPs divide the network into zones called Zone of Relevance “ZOR”.
• All nodes in this zone are within wireless transmission range without
intermediate node.
Geo-cast Routing Protocols
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49. • If the node is in another “ZOR”, the source node will define a
forwarding zone
• Zone of forwarding “ZOF” will be used to flood the packets in the
forwarding zone instead of in the entire network.
• Each packet carries the full route in its header. that increases
the overhead.
• The are various GRPs such as: IVG, DG-CASTOR and DRG
Geo-cast Routing Protocols-
Cont’
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50. Cluster Based Routing Protocols
• CBRPs divide the network into interconnected virtual network called cluster.
• Nodes identifies themselves to be a part of cluster & periodically broadcast Hello
message to its neighbors.
• One of the nodes in the cluster will be elected as cluster head and act as medium for
packet transfer.
• Cluster head from different clusters communicate with each other using gateway node.
• CBRPs are good for large networks ; in highly mobile VANET delay will occur.
• The various Clusters based routing protocols such as: CBDRP.
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51. Broadcast Routing Protocols
• BRPs enable packets to be flooded to all nodes in the network (one to many).
• BRPs mainly used in the route discovery process.
• BRPs could consume the network bandwidth by sending replicated packets, so
each node need to identify which packet has received before to discard it.
• BRP is mostly used for sharing information like traffic, weather , road conditions
and delivering advertisements and announcements.
• The various Broadcast routing protocols are BROADCOMM, UMB and V-TRADE
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52. • Technical Challenges
• Social and Economic Challenges
VANET Challenges
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53. Technical Challenges
• Network Management
o Due to high mobility, the network topology and channel condition change rapidly
o Due to this, we can’t use structures like tree because these structures can’t be set
up and maintained as rapidly as the topology changed
• Congestion and collision Control
o The unbounded network size also creates a challenge.
o The traffic load is low in rural areas and night in even urban areas. Due to this, the
network partitions frequently occurs while in rush hours the traffic load is very
high and hence network is congested and collision occurs in the network
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54. Technical Challenges
• Environmental Impact:
o VANETs use the electromagnetic waves for communication. These waves
are affected by the environment. Hence to deploy the VANET the
environmental impact must be considered
• Security:
o As VANET provides the road safety applications which are life critical
therefore security of these messages must be satisfied.
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55. Social and Economic Challenges
• It is difficult to convince manufacturers to build a system that conveys the traffic
signal violation because a consumer may reject such type of monitoring. Conversely,
consumer appreciates the warning message of police trap. So to motivate the
manufacturer to deploy VANET will get little incentive.
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56. • Security Challenges in VANET
• Security requirements in VANET
• Attackers on Vehicular Network
• Attacks in the VANET
VANET Security Issues
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57. Security Challenges in VANET
• Real time Constraint
o VANET is time critical where safety related message should be delivered
with 100ms transmission delay. So to achieve real time constraint, fast
cryptographic algorithm should be used. Message and entity
authentication must be done in time.
• Data Consistency Liability
o VANET even authenticate node can perform malicious activities that can
cause accidents or disturb the network. Hence a mechanism should be
designed to avoid this inconsistency. Correlation among the received
data from different node on particular information may avoid this type
of inconsistency.
• Low tolerance for error
o Some protocols are designed on the basis of probability. VANET uses life
critical information on which action is performed in very short time. A
small error in probabilistic algorithm may cause harm.
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58. Security Challenges in VANET
• Key Distribution
o All the security mechanisms implemented in VANET dependent on keys. Each
message is encrypted and need to decrypt at receiver side either with same key or
different key. Also different manufacturer can install keys in different ways and in
public key infrastructure trust on CA become major issue. Therefore distribution
of keys among vehicles is a major challenge in designing a security protocols.
• Incentives
o Manufactures are interested to build applications that consumer likes most. Very
few consumers will agree with a vehicle which automatically reports any traffic
rule violation. Hence successful deployment of vehicular networks will require
incentives for vehicle manufacturers, consumers and the government is a
challenge to implement security in VANET
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59. Security Challenges in VANET
• High Mobility:
o The computational capability and energy supply in VANET is
same as the wired network node but the high mobility of VANET
nodes requires the less execution time of security protocols for
same throughput that wired network produces. Hence the design
of security protocols must use the approaches to reduce the
execution time.
 Two approaches :
• Low complexity security algorithms
• Transport protocol choice
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60. Security Challenges in VANET
• First Approach:
o Low complexity security algorithms:
 Current security protocols such as SSL/TLS generally uses RSA based public key
cryptography. RSA algorithm uses the integer factorization on large prime no. which
is NP-Hard. Hence decryption of the message that used RSA algorithm becomes very
complex and time consuming. Hence there is need to implement alternate
cryptographic algorithm like Elliptic curve cryptosystems and lattice based
cryptosystems . For bulk data encryption AES can be used.
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61. Security Challenges in VANET
• Second Approach:
o Transport protocol choice:
 To secure transaction over IP, DTLS should be preferred over TLS as DTLS operates
over connectionless transport layer. IPSec which secures IP traffic should be avoided
as it requires too many messages to set up. However IPSec and TLS can be used
when vehicles are not in motion.
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62. Security requirements in VANET
• Authentication
▫ ensures that the message is generated by the legitimate user. In VANET a
vehicle reacts upon the information came from the other vehicle hence
authentication must be satisfied
• Availability
▫ requires that the information must be available to the legitimate
users. DoS Attacks can bring down the network and hence
information cannot be shared.
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63. Security requirements in VANET
• Non-Repudiation
 A node cannot deny that he/she does not transmit the message. It
may be crucial to determine the correct sequence in crash
reconstruction.
• Privacy
▫ The privacy of a node against the unauthorized node should be
guaranteed. This is required to eliminate the massage delay attacks.
• Data Verification
▫ A regular verification of data is required to eliminate the false messaging.
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64. Attackers on VANET
• Insider and Outsider
▫ Insiders are the authenticated members of network whereas Outsiders are
the intruders and hence limited capacity to attack
• Malicious and Rational
▫ Malicious attackers have not any personal benefit to attack; they just harm
the functionality of the network. Rational attackers have the personal profit
hence they are predictable.
• Active and Passive
▫ Active attackers generate signals or packet whereas passive attackers only
sense the network
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65. 65

66. Attacks in the VANET
• Impersonate:
▫ Attacker assumes the identity and privileges of an authorized
node, either to make use of network resources that may not be
available to it under normal circumstances, or to deactivate the
normal functioning of the network.
▫ Done by Active attackers who can be insider or outsiders.
▫ It is multilayer attack : means attacker can exploit either network
layer, application layer or transport layer vulnerability. This
attack can be performed in two ways:
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67. Attacks in the VANET
• Impersonate performed in two ways:
1. False attribute possession: In this scheme an attacker steals
some property of legitimate user and later with the use of
attribute claims that it is who (legitimate user) that sent this
message. By using this type attack a normal vehicle can claim
that he/she is a police or fire protector to free the traffic.
2. Sybil : In this type of attack, an attacker use different
identities at the same time.
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68. Attacks in the VANET
• Session hijacking:
▫ Most authentication process is done at the start of the session. Hence it is easy to hijack the
session after connection establishment. In this attack attackers take control of session
between nodes.
• Repudiation
▫ The main threat in repudiation is denial or attempt to denial by a node involved in
communication. This is different from the impersonate attack. In this attack two or more
entity has common identity hence it is easy to get indistinguishable and hence they can be
repudiated.
• Eavesdropping
▫ It is a most common attack on confidentiality. This attack is belongs to network layer attack
and passive in nature. The main goal of this attack is to get access of confidential data.
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69. Attacks in the VANET
• Bogus Information:
▫ Attacker sends false information in the network for personal
benefit. For example a malicious node can send false information
of heavy traffic due to an accident over road and can make its
route clear.
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70. 70

71. Deployment of VANET in Real
Scenarios
• In 1970, the electronic Route Guidance system (ERGS) was proposed in USA.
• From 1973 to 1979, the Comprehensive Automobile Traffic Control System (CACS)
project was deployed in Japan - Nakahara and Yumoto.
• In 1986, the Program for European Traffic with Highest Efficiency and
Unprecedented Safety (ROMETHEUS) in Europe was initiated.
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72. References:
• Mourad Elhadef, “An Adaptable in VANETs-Based Intersection Traffic Control Algorithm,”
http://ieeexplore.ieee.org/document/7363399/
• http://www.mogi.bme.hu/TAMOP/jarmurendszerek_iranyitasa_angol/math-index.html
• airccse.org/journal/ijcses/papers/0211cses10.pdf
• https://www.researchgate.net/publication/51930350_A_Comparative_Study_of_Various_Routi
ng_Protocols_in_VANET
• https://www.researchgate.net/publication/286321699_A_comparative_study_of_Routing_Prot
ocols_in_VANET
• https://arxiv.org/ftp/arxiv/papers/1204/1204.1201.pdf
• http://www.sciencedirect.com/science/article/pii/S2214209614000187?np=y
• iceeot.org/papers/OR0389.pdf
• http://www.intechopen.com/books/vehicular-technologies-deployment-and-applications/smart-
vehicles-technologies-and-main-applications-in-vehicular-ad-hoc-networks#article-front
• http://www.mogi.bme.hu/TAMOP/jarmurendszerek_iranyitasa_angol/math-ch14.html
• http://dsn.sagepub.com/content/11/8/745303.full#ref-36
• http://airccse.org/journal/nsa/5513nsa08.pdf
• https://www.researchgate.net/figure/262879294_fig1_Fig-1-VANET-components-modified-
from-13
• http://www.ijser.org/paper/Study-of-Efficient-Routing-Protocols-for-VANET.html
• http://www.slideshare.net/sudhansudash9/cluster-based-routing-protocol
• https://www.scribd.com/document/281289151/A-Study-of-Geocast-Routing-Protocols-in-
Vehicular-Ad-Hoc-Network-VANET
• http://www.driverfocusedhmi.com/
• http://ijcsse.org/published/volume4/issue8/p2-V4I8.pdf
• http://www.mlit.go.jp/road/ITS/5Ministries/chap1.html
• https://dot.abudhabi.ae/en/info/Integrated_Intelligent_Transportation_Systems_Division
• http://www.intechopen.com/books/contemporary-issues-in-wireless-communications/reliable-
communication-in-cooperative-ad-hoc-networks
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