On-Road Caching Assistance for Ubiquitous Vehicle-Based Information Services

Smart vehicles are considered major providers of ubiquitous information services. In this paper, we propose a solution for expedited and cost-effective access to vehicular public sensing services. The proposed caching-assisted data delivery (CADD) scheme applies caching on the delivery path of the collected data. Cached information can be used for later interests without having to request similar data from vehicles. For the operation of CADD, we introduce a lightweight road caching spot (RCS) to work as an on-road caching and forwarding assistant. CADD utilizes these caching spots along with vehicles on roads for handling the data collection and delivery processes. The proposed scheme involves a novel caching mechanism that utilizes real-time information for selecting the caching RCSs while considering popularity in cache replacement. A data chunk to be replaced may be forwarded to another less-loaded RCS. CADD considers vehicles´ headings to direct communication toward the destination. Mathematical analysis and a simulation-based evaluation of the scheme are conducted. The evaluation results show significant improvements achieved by CADD in terms of access cost, delivery delay, and packet delivery ratio, compared with other schemes that do not involve caching assistance and do not take vehicles´ headings into consideration.