Instantly decodable network coding–assisted data dissemination for prioritized services in vehicular ad hoc networks

Safety-related and user-related applications are two main kinds of services provided in vehicular ad hoc networks. Safety-related applications have great impact on vehicles and people who participate in the transportation. The quality requirements for safety data dissemination are strictly high, since this kind of service is usually concerned with the most important safety events in vehicular ad hoc networks. Meanwhile, user-related applications need to fulfill the varied demands for value-added services of consumers in vehicular ad hoc networks to retain existing consumers and to attract new ones. However, the unpleasant transmission environment of vehicular ad hoc networks, such as drastically changing network topology and unstable communication links, degrades the system performance and hinders the development of vehicular ad hoc networks. To tackle these issues, this article proposes a novel algorithm which prioritizes data based on their service purposes and schedules the most rewarding data item based on utility values calculated with multiple parameters, including data requirements of vehicles, vehicles density, speeds, and locations. Moreover, the algorithm applies instantly decodable network coding technique on the scheduled data to maximize the multicast throughput. Simulation results approve the performance advancement of the proposed algorithm in download delay, deadline miss ratio, and download success ratio for high- and low-priority data disseminations.