Efficient Routing for Safety Applications in Vehicular Networks

In recent years, both the car industry and the government have recognized the tremendous promise of vehicular ad hoc network technology in improving the safety of drivers, passengers, and pedestrians. There are a number of envisioned applications, that can both reduce the number of accidents, e.g. via intelligent car to car communication, and reduce the impact of non-avoidable accidents, e.g. via post-crash warnings. The department of transportation and a number of industry consortiums on both sides of the Atlantic are actively involved in this promising area of research. To make such applications a reality, it is imperative to design networking protocols that can route messages between rapidly-moving vehicles. The challenge comes from the large speeds of moving vehicles, which renders wireless links between them useless after short periods of time, and the intermittently connected nature of the network, since there is no guarantee that the density of vehicles in a surface street or highway is going to be large enough to establish contemporaneous paths between senders and receivers of safety information. To address this challenge, this proposal plans to use a new approach of routing that is tailored to the needs of vehicular ad hoc networks and is termed by the PI as "mobility-assisted routing." Mobility-assisted routing departs drastically from the traditional view of network routing: When a node (moving vehicle or a roadside station) wants to send a message to one or more nodes, it may transmit a number of copies of the message to one or more distinct relay nodes. Each relay will carry the message further, and may transmit it to a new, better relay or directly to a destination. Thus, vehicle mobility is used as an ally to route information between vehicles and stations along the roads. The primary objective of this proposal is to design highly efficient routing schemes for vehicular ad hoc networks (VANETs), which are tailored to support real-life safety-related applications. Specific safety applications will be used as showcases to establish the efficiency of the proposed routing algorithms. Realistic simulations that use real roadmaps and mobility traces, and formal analysis that takes real-life limitations into account will be used to access the resulting performance. The principal investigator (PI) has significant amount of work in the area of routing for mobile ad hoc networks that may be intermittently connected. This prior work will be very useful in re-designing, implementing, and testing such routing algorithms in the specific context of VANETs discussed above.