Book Description

The growing demand to improve road safety and optimize road traffic has generated great interest in vehicular ad-hoc network (VANETs). Serious traffic accidents can cause financial losses, physical disability, and even death. However, if drivers were informed about the danger in advance through a warning message, this would give drivers enough time to react appropriately to the situation. There are many approaches that can prevent car accidents, and VANETs have been conceived as an excellent solution to improve road safety, through the use of a variety of applications enabled by vehicle communications. The key objective of this research is to achieve information dissemination from a vehicle to other vehicles around that migth be interested in receiving the content. We focus on the network layer and application layer protocols, which are discussed and developed as a protocol over the respective access technologies. We primarily present the research results of our proposals, and also provide a comprehensive review of existing challenges and solutions in data dissemination in VANETs. Our proposals include the design of three dissemination protocols compatible with the IEEE 802.11p standards for road safety applications. These dissemination protocols can be differentiated by their application trigger condition and the broadcast scheme. All three dissemination protocols have been implemented in the simulator VEINS to perform several large-scale experiments. The results of the experiments have shown that all three dissemination protocols are able to cope with an increasing number of vehicles in large scale scenarios without sufering a noticeable loss in performance. Finally, we have investigated solutions to increase the driver's privacy because VANETs can also introduce some location privacy risk by periodically broadcast beacon messages that include the vehicle's position. We evaluate the performance of the privacy schemes, described the experiments and discussed the results.