This document discusses Vehicular Ad-Hoc Networks (VANETs). It defines VANETs as a technology that uses vehicles as nodes in a mobile network to communicate among nearby vehicles and with roadside equipment. The document outlines the motivation for VANETs as improving safety by preventing road accidents and optimizing traffic flow. It also describes the differences between VANETs and mobile ad-hoc networks, provides a schematic of a VANET, and discusses VANET architecture, applications such as collision warnings, and current research being done in both the US and Europe.

1. VEDANT A. GODHAMGAONKAR

2. AGENDA
 Introduction
 Schematic Representation of a VANET
 Vehicular Communication
 VANET Architecture
 Applications of VANET
 Characteristics
 Current Research
 Conclusion
 References

3. WHAT IS VANET?
 A VANET, is a technology that uses moving cars as
nodes in a network to create a mobile network.
 It is used to provide communications among nearby
vehicles and between vehicles and nearest fixed
equipment, usually described as roadside equipment.
 “VANET make transportation systems more intelligent”

4. Motivation for VANET
 Increase safety
Hundreds of thousands of people are killed world-
wide due to road accidents yearly.
Many more are injured.
 Traffic optimization
Congestion/traffic jams cost time and fuel.
Both these problems can be solved
by giving timely information to the drivers!

5. Differences from MANET
MANETs VANETs
 Unicast and Multicast protocols
in MANETs
 Majority of nodes in MANETs
dependent on batteries for their
energy.
 Unavailability of infrastructure
 VANETs use broadcasting to
provide important control and
route establishment.
 VANET nodes are vehicles, so
there are less power and storage
constraints.
 Fixed infrastructure for VANETs

6. Schematic Representation of
a VANET

7. Vehicular Communication
 VANET communicates through Wireless Access for
Vehicular Environments (WAVE).
 The WAVE uses different types of Wireless
Commutation devices such as (Wi-Fi / Wi-Max).
 The sensors or wireless devices can form a VANET
network which resides on top of the vehicle.

8. Cont…

9. Protocol used in VANET
 There are no standardized protocols, but a lot of research is
going on in this area. Likewise these are some of the
protocols…
 AODV (Ad hoc On-Demand Distance Vector)
 OLSR (Optimized Link State Routing Protocol)
 DYMO (Dynamic MANET On-Demand)
 DSRC (Dedicated Short Range Communication)
 CALM (Cont Air interface for Long & Medium distance)
 CVIS (Cooperative Vehicle-Infrastructure System)
 OFDM (Orthogonal Frequency Division Multiplexing)

10. VANET ARCHITECTURE

11.  Staircase approach: An application can select among
multiple service access points to lower layers.
 Single-hop layer: communication to direct radio
neighbors.
 Multi-hop layer :forwarding packets to non
neighbored nodes using neighbors as forwarders.
 Information connector: offering an interface to
events such as “Position Update Events” or “Neighbor
Position Change Events”.

12. IMPLEMENTING PROTOCOLS
In cases of emergencies, the protocol is used to open an instant
communication channel with the vehicle in the most dangerous
situation.
 Unicast information packed in a broadcast protocol
 Belongs to: Reliable Protocols for a Specific Purpose
12

13. Application: Congestion
Detection
 Relay congestion information
Hop-by-hop message forwarding
Other vehicles can choose alternate routes

14. Cont...
Co-operative Collision Warning Lane Change Warning Intersection Collision Warning
Approaching Emergency vehicle Rollover Warning Work Zone Warning
Coupling/Decoupling Inter-Vehicle Communications Electronic Toll Collection

15. VANET Characteristics
The main characteristics of VANETs
 High mobility of nodes
 No prior information about location of nodes
 Predictable topology (to some extent)
 The communication link in a VANET is short lived
 No problem with power
 High possibility to be fragmented

16. Current Research
 USA:
1)Vehicle Safety Communications Consortium(VSCC)
2)DSRC/WAVE Technology
3)Vehicle Infrastructure Integration (VII)
 Europe:
1)Car to Car Communication Consortium
2)Network on Wheels (“NOW”)(Germany)
 Japan:
Internet ITS Consortium

17. Conclusions
 VANETs have many practical applications, but the
most important ones are in terms of active safety.
 There are no standardized protocols, but a lot of
research is going on in this area.
 VANETs are likely to become the most important
realization of mobile ad hoc networks.

18. REFERENCES
 http://pcquest.ciol.com/content/technology/2009/1090201
01.asp
 http://en.wikipedia.org/wiki/Vehicular_ad-
hoc_network#Applications
 http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=4
458046
 http://aivanetblog.blogspot.com/
 Ad-hoc wireless network by MURTHY MANOJ

19. THANK YOU…!!!