-Internet On Road

INTRODUCTION Driving means constantly changing location. This, in turn, means a constant demand for information on the current location and specifically for data on the surrounding traffic. In particular, there is a demand for sensor data from other cars such as data on braking sent from a preceding car, for data on the traffic flow on a route, and for information about sites located along a route. To promote the development of such an inter-vehicle communication system “FleetNet-Internet on the Road” was introduced.

CLASSIFICATION Classification of Fleetnet

OBJECTIVES OF FLEETNET The objectives of FleetNet are: To develop a communication platform for inter-vehicle communications. To implement demonstrator applications. To develop promising introduction strategies and To standardize the solutions found in order to improve drivers’ and passengers’ safety and comfort.

KEY FEATURES Wireless multi hop ad hoc networking extends the ‘range of awareness’. Considering unlicensed radio frequency bands allows for low cost data transmission. Very low data transmission delay is suitable for cooperative driver assistance and safety related applications. Vehicles are addressed according to their position inherently enabling position-based routing and location-based services. Vehicle to vehicle and vehicle to fixed roadside station communication enables Internet access and Internet integration. open solutions to be standardized and open to other vehicle manufacturers.

CAR TO CAR COMMUNICATION-A KEY TO SAFETY For drivers of vehicles, information about their immediate vicinity is crucial for being able to drive safely. So far most information is gathered by direct visual observation and in response to sounds. Apart from that providing better guidelines to the driver other than the observations made by him from his surroundings will definitely help him in driving to have a secure journey. The vision of vehicle-to-vehicle and vehicle-to roadside communication is that information available in cars, such as from sensors and instruments, can be quickly passed on to others in the immediate vicinity, by means of this ad hoc network communication. The extension of sensory information allows drivers to react more quickly to emergency situations, e.g., cars ahead braking.

INTER-VEHICLE COMMUNICATION PLATFORM There are four ways of inter-vehicular communication: Car-to-car direct Car-to-car via relaying by intermediate cars Car to stationary FleetNet gateway Car-Internet via stationary FleetNet gateway

FLEETNET ROUTING This is also called as position based routing. FleetNet routing assumes that vehicles are aware of their geographical position. By making use of position-based routing strategies, an improved scaling behavior and adaptability with respect to large and highly dynamic networks can be achieved compared to non-position-based approaches (cont..)

The requirements for implementing the greedy position based algorithm are: 1. Each node should be aware of its position and position of its neighbors 2. Location service maps node ID’s to their current geographic position. 3. Strategies to handle positional errors 4. Greedy forwarding + recovery strategy

IMPLEMENTATION OF GREEDY BASED ALGORITHM The implementation of the above algorithm includes the following steps: - each node owns its position (xi, yi). - the nodes send their periodic beacon packets with their position and node ID. - the information is stored in neighbor table. - after one round the neighbor table is cleared. This state is also called as “soft state”.

Packet forwarding employs one of the following mechanisms: REACTIVE: It is a two way user-system- request-response. INTERACTIVE: it is a mutual way of forwarding the packets. This can be employed when a continuous communication between two users would be going on. PROACTIVE: the packets are sent to the system from the user and this system resends the received packets to the actual sensor.

EXAMPLE The storage of information in the neighbor would be in the following manner: 1 [2] → 2 [1,3] → 3 [2,4] → 4 [3]

RADIO COMMUNICATION Routing, sending the packets everything is done perfectly but this system needs an interactive tool in order to convey the messages to the driver. This gives rise to the introduction of radio communication systems. The requirements on the FleetNet radio communication system are: 1. support of high bit rates; 2. Robustness in case of high relative velocities; 3. Provisioning of multi hop connectivity even in low traffic density scenarios; and 4. Operation in unlicensed frequency bands.

APPLICATIONS 1.Cooperative driver assistance, e.g. Emergency notification Overtaking assistance Obstacle warning 2. Decentralized floating car data, e.g. Traffic jam monitor Dynamic navigation Route weather forecast 3. User communications and information services, e.g. Hot-spot Internet access Inter-vehicle chat Distributed games

DISADVANTAGES The warnings are displayed in the form of geographical coordinates. It can be used for fun also but if used in a wrong manner, fleetnet can be used to send some abusing messages or fake messages. This also is pruned to hacking. This network can also be hijacked and may result in traffic hazards as the attacker can broadcast fake positions to the vehicles.

CONCLUSION Fleet Net is a feasibility study made to bring a car-to- car communication system from an idea into the real world. Starting from the idea for a vehicular ad hoc network by using geographical positions for communications in a vehicular ad hoc network, we were able to know the benefits of this approach by means of network simulations. In order to develop car-to-car communication to a mature technology, we came to know about enhancing the communication protocols using an approach of modeling, simulation, implementation, and measurements for continuous and sustainable improvement.

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