Connectionless Edge-Cache Servers for Reducing Cellular Bandwidth Usage in Vehicular Networks

This paper presents a novel caching mechanism based on Connectionless Edge Cache Servers in vehicular networks. The goal is to intelligently cache content within the vehicles and the edge servers so that majority of the vehicle-requested content can be obtained from those caches, thus minimizing the amount of cellular network usage needed for fetching content from a central server. A notable feature of the cache servers in this work is that they do not have backhaul connectivity. This makes the connectionless servers to be relatively less expensive compared to the usual Roadside Service Units (RSUs), and potentially moveable in response to specific events that are expected to generate content in large volumes. In the absence of backhaul connectivity in the edge servers, the vehicles ferry content across the edge servers to build optimal cached content distribution so that the cellular usage from the vehicles is minimized. We have implemented the scheme using ONE simulator and compared it with various other caching mechanisms including a manually pre-filled technique that provides a performance upper bound. It was shown that the proposed mechanism outperforms the other schemes in two different network scenarios, one based on East Lansing (MI) map, and the other based on a synthetic transportation network.