Zone-based Popularity-Oriented Multi-Layer Content Caching in Vehicular Fogs

Caching in vehicular fog infrastructure has been explored to deal with the problems related to vehicular networks, but it still needs efficient data management strategies to deal with high mobility and dynamic network topology. A multilayer caching approach enables faster data access and processing through a hierarchical structure that handles requests at an appropriate fog level, reducing latency and improving overall system efficiency. However, storing random content following the mobility of vehicles can result in cache pollution when overloaded with information that is unlikely to be used again, lowering cache hits and decreasing its effectiveness. Therefore, we propose a multi-layer distributive transient cache with adhering zone-based popularity-centric caching strategy to generate improved cache hits, reduce content request latency, and place cache content closer to the requester to provide better data availability. This fogoriented caching technique showed enhanced data management through comprehensive analyses of simulated realistic urban scenarios - an improvement of 2.2% of cache hits and a reduction of 1.7ms of fetching latency.

I. Introduction

Fog computing is an innovative distributed computing infrastructure that employs devices placed at network edges to enable efficient communication through collaborative caching facilities. This approach is highly versatile in connecting fog nodes with vehicles, as it significantly reduces the processing load on individual devices and minimizes data retrieval latency. Essentially, to deploy computer resources and services close to the users, fog computing was developed as an extension of cloud computing. By providing a local cache with data processing capabilities, it can also rapidly respond to enduser needs [1]. However, effective cache management in fog networks associated with vehicles is beset with numerous challenges that require careful consideration. Such challenges include ensuring cache consistency, dealing with limited storage capacity, managing cache replacement policies, and vehicular mobility.