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 Inter-net and a vehicular ad hoc network (VANET)for developing a next generation of ubiquitous communication infrastruc-ture and improving universal information and service ac-cessibility. A key optimization technique in IVANETs is to cache frequently accessed data items in a local stor-age 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 invali-date them when data items are updated. This is particularly a concern due to vehicles' high-speed mobility. In this pa-per, we propose a novel cache invalidation algorithm that takes advantage of the underlying location manage-ment scheme to reduce the number of broadcast operations and the corresponding query delay. Numerical results in-dicate that the proposed scheme significantly reduces the communication cost, and thus is proven to be a viable solution for IVANETs.