Content in Motion: A Novel Relay Scheme for Content Dissemination in Urban Vehicular Networks

Content dissemination, in particular small-volume popular content dissemination, represents a killer application of vehicular networks, which is also fundamental to the delivery of advanced infotainment applications, such as vehicular social networks, road traffic alerts, etc. The content dissemination in vehicular networks relies on moving vehicles to relay and propagate contents. Due to challenges including diverse mobilities of vehicles, strict timeliness and limited vehicular communication bandwidth, to appropriately select the relay vehicles towards the optimal system performance is a challenging task. This paper investigates the issue by devising a novel content dissemination scheme composed of two phases. In the first phase, contents are uploaded to a road-side cache infrastructure called roadside buffer (RSB). By examing the transmission capability of vehicles, the RSB then selectively disseminates content files to drive-thru vehicles with an optimal relay selection scheme. In the second phase, the vehicles selected by the RSB relay the content to other vehicles which have interest in the content during the trip to destinations. Using extensive simulations, we show that our scheme disseminates content to vehicles more efficiently than the conventional method.