  We consider content distribution in vehicular ad hoc networks. We assume that
a file is encoded using fountain code, and the encoded message is cached at
infostations. Vehicles are allowed to download data packets from infostations,
which are placed along a highway. In addition, two vehicles can exchange
packets with each other when they are in proximity. As long as a vehicle has
received enough packets from infostations or from other vehicles, the original
file can be recovered. In this work, we show that system throughput increases
linearly with number of users, meaning that the system exhibits linear
scalability. Furthermore, we analyze the effect of mobility on system
throughput by considering both discrete and continuous velocity distributions
for the vehicles. In both cases, system throughput is shown to decrease when
the average speed of all vehicles increases. In other words, higher overall
mobility reduces system throughput.
