Optimal caching of encoded data for content distribution in vehicular networks

Vehicular communications have gained momentum as a means to coordinate vehicular traffic by disseminating information about the road status and traffic conditions. However, over the time, vehicular applications have changed towards being driven by exchanging and accessing multimedia information. Such applications have therefore evolved and become very greedy in terms of transmitted traffic and used bandwidth. In this paper, we introduce a dynamic data placement scheme to improve data dissemination in vehicular networks. We highlight that, while the cost of storage memory decline over the years, storing all files in all Road Side Units results in a inefficient use of network resources. Our work selects only a subset of Road Side Units to store coded pieces of data that are later made available to all vehicles through the network. We formulate the data placement as an optimization problem to minimize the delivery time between each vehicle and the Road Side Units. Our experiments show that optimally placing coded data in the network greatly improves the network performance of existing VANET file swarming protocols.