Ivy: Interest-based data delivery in VANET through neighbor caching

In this paper, we study the problem of interest-based data delivery in Vehicular Ad Hoc Networks (VANETs), which is to efficiently forward data to a vehicle that owns the given interest without knowing its ID beforehand. Such problem is generally challenging in large-scale distributed networks, because it usually requires to query a huge number of nodes in the network to find a node of interest out of them, which is costly. To tackle the problem, we design an interest-based data delivery (Ivy) scheme through neighbor caching to boost the efficiency in querying information of the vehicle with given interest. We let each vehicle cache the information of all the neighbor vehicles it meets during driving, such that by just querying a few vehicles, a vehicle can retrieve the information of a large amount of vehicles, which greatly reduces the message overhead. To further reduce the message cost in route establishment, we calculate an estimated current location of the interested vehicle and forward data towards the calculated location, which avoids broadcasting blindly to search for the vehicle. Simulation result shows Ivy is both efficient and effective, and outperforms existing data delivery schemes with higher delivery ratio, lower delay and smaller message overhead.