What is Ad-Hoc?About Vehicular Ad-Hoc NetworksVNET Communication architecture.Intelligent transport system.

Structure of modern vehicle

Communication typesI. Inter vehicleII. Roadside to vehicle

Current work in VNET,Application,summary

Agenda:

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Perspective – What’s Ad-Hoc?

"Ad Hoc" is actually a Latin phrase that means "for this purpose.“ It is often used to describe solutions that are developed on-the-fly for a specific purpose. In networking, an ad hoc network refers to a network connection established for a single session and does not require a router or a wireless base station.

Vehicles transformed into “Computers on the wheels” or “networks on the wheels.Ad-hoc means a system a systems of network elements that combine to a form a network require little or no more planning of communication between v2v.

The participating nodes in this network Can interact and cooperate with each other by short range communication.

On board unit inside the vehicle gives information About condition & is responsible for commmunicate with the other vehicle.

The Vehicular Ad hoc Network (VANET) has emerged as a new technology to offer solutions for Intelligent Transportation Systems (ITS) that aim at helping drivers on the roads by anticipating hazardous events or avoiding bad traffic areas.

Briefly About VNET

Vehicular Ad Hoc Network Communication is the wide area of research topic for Wireless technologies in educational

environment as well as automobile industry.

Basically Vehicular Ad Hoc Network (VANET's) technically based upon the Intelligent Transportation Systems.

Vehicular to Vehicular (V2V) communication is efficient due to various reasons like short range, cheapest Communication and better bandwidth.

VANET is a subgroup of MANET where the nodes refer to vehicles. Since the movement of Vehicles are restricted by roads, traffic regulations

A Modern Vehicle

(GPS) Positioning system Forward radar

Communication

facility

Rear radar

Computing platform Display Human-Machine Interface

A modern vehicle is a network of sensors/actuators on wheels !

Event data recorder (EDR)

Communication architecture

1. The protocol stack consists of five layers and three planes.

2. The planes are to help sensor node to coordinate the sensing tasks and lower overall power consumption.

The protocols stack which may be used by VNET nodes is given in figure -

More specifically, the power management plane, manages power consumption for example defining sleep and wake status for thenodes. The mobility management plane monitors the movement of sensor nodes, so a route back tothe user is always maintained. And finally, the task manager plane balance and coordinates thesensing tasks given to a particular given region.

Physical LayerFederal Communications Commission (FCC) [17] assigned a new 75 MHz band Dedicated ShortRange Communication (DSRC) at the 5.9 GHz frequency for Intelligent Transportation Systems (ITS) applications in North America. The band is divided into seven channels as abstracted in the following figure

Data link layer

The datalink layer operates on an individual link or subnetwork part of a connection, managing the transmission of the data across a particular physical connection .Therefore, some mechanisms for service differentiation and admission control are indispensable. In fact, we can define three levels of priority for messages in VASNET:

(1) event driven safety messages, (2) beaconing safety messages, (3) comfort messages respectively in descending order.

The required mechanisms are dependent on MAC layer policy.

Network layer:

Responsible for source to destination delivery of packet.The network layer sets up and manages an end-to-end connection across a single real network,

determining which permutation of individual links need be used and ensuring the correct transfer of

information across the single network.VNET inherits network layer issues from traditional wireless sensor networks and mobile Ad Hoc networks (MAENT) such infrastructures, unstable topology, multi-hop networking, energy efficiency data-centric ,routing localization, etc.

Transport layer

This makes a bursty traffic in to the network. Significant sensory data must be reliably delivered to thebase station to obtain detection and tracking an event signal. Simultaneously, if the multi-hop network capacity exceed, congestion is the result.

the splitting capability of the transport protocol allows one sessionto be conducted over a number of parallel network communication paths.

Application layer

In case of wireless sensor networks, application layer may be responsible for some functions like

generation of information, interest and data dissemination, feature extraction of event signals, and data aggregation and fusion. However, in our proposed system, these services have to

utilize the capabilities of VNET while conforming to its constraints.

Communication types• Inter-vehicle communication(IVC)• Vehicle to Vehicle (V2V)• Vehicle to Roadside/infrastructure (V2R/V2I)

Hybrid Models

• Vehicle to Vehicle (V2V) & Vehicle to Infrastructure (V2I)• Vehicle to Vehicle (V2V) & Vehicle to Roadside (V2R)

•A wireless transceiver that transmits and receives data to/from the neighboring vehicles and roadside•A GPS receiver that provides relatively accurate positioning and time synchronization information•Appropriate sensors to measure the various parameters that have to be measured and eventually transmitted•An input/output interface that allows human interaction with the system

Inter-vehicle communication (IVC) Systems The inter-vehicle communication configuration (Fig. 1) uses multi-hop multicast/broadcast to transmit traffic related information over multipleThere are two types of message forwarding in inter-vehicle communications: naïve broadcasting and intelligent broadcasting hops to a group of receivers

Vehicle-to-Roadside Communication (RVC) Systems

The vehicle-to-roadside communication configuration(Fig) represents a single hop broadcast where the roadsideunit sends a broadcast message to all equipped vehicles

Vehicle-to-roadside communication configuration providesa high bandwidth link between vehicles and roadsideunits.

• Vehicle to Infrastructure provides solution to longer-range vehicular networks.

• It makes use of preexisting network infrastructure such as wireless access points (Road-Side Units, RSUs).

• Communications between vehicles and RSUs are supported by Vehicle-to-Infrastructure (V2I) protocol and Vehicle-to-Roadside (V2R) protocol.

• The Roadside infrastructure involves additional installation costs.

Vehicle to vehicle • Vehicle to Vehicle communication approach is most suited

for short range vehicular networks.• It is Fast and Reliable and provides real time safety• It does not need any roadside Infrastructure.• V2V does not have the problem of Vehicle Shadowing in

which a smaller vehicle is shadowed by a larger vehicle preventing it to communicate with the Roadside infrastructure.

Application of VANET

Public Safety Traffic Management Traffic Coordination ApplicationsTraveller Information Support ApplicationsComfort ApplicationsBroadband services.

Current work :Currently there is ongoing research in the field of InVANETs for several scenarios. The main interest is in applications for traffic scenarios, mobile phone systems, sensor networks and future combat systems. Recent research has focused on topology related problems such as range optimization, routing mechanisms, or address systems, as well as security issues like traceability or encryption. In addition, there are very specific research interests such as the effects of directional antennas for InVANETs and minimal power consumption for sensor networks

Summary:1. Improves the safety of the vehicles.2.Vehicular Ad Hoc Networks (VANET) upon

implementation should collect and distribute safety information.

3. So massively reduce the number of accidents.4.The rapid advancement of wireless

communications and information technologies are revolutionizing many aspects of the human lifestyle.

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ReferencesVEHICULAR AD HOC AND SENSOR NETWORKS PRINCIPLES AND CHALLENGES,pdfby Mohammad Jalil Piran1, G. Rama Murthy2, G. Praveen Babu3Vehicular ad hoc networks (VANETS): status, results,and challenges,paper by Sherali Zeadally · Ray Hunt · Yuh-Shyan Chen · Angela Irwin · Aamir Hassan

Data Networks, IP and the Internet book.Willey

Electronic journal

www.google.com.

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Questions?