On cache invalidation for internet-based vehicular ad hoc networks

Internet-based vehicular ad hoc network (IVANET) is an emerging technique that combines a wired Internet and a vehicular ad hoc network (VANET) for developing a next generation of ubiquitous communication infrastructure and improving universal information and service accessibility. A key optimization technique in IVANETs is to cache frequently accessed data items in a local storage of vehicles. Since vehicles are not critically limited by the storage space, it is a less of a problem which data items to cache. Rather, a critical design issue is how to invalidate them when data items are updated. This is particularly a concern due to vehiclespsila high-speed mobility. In this paper, we propose a novel cache invalidation algorithm that takes advantage of the underlying location management scheme to reduce the number of broadcast operations and the corresponding query delay. Numerical results indicate that the proposed scheme significantly reduces the communication cost, and thus is proven to be a viable solution for IVANETs.