The Impact of Vehicular Traffic Demand on 5G Caching Architectures: a Data-Driven Study

TL;DR

This study analyzes how vehicular traffic impacts 5G caching architectures, demonstrating that mobile edge caching significantly reduces core network load, especially with location-specific content demand, using real-world data.

Contribution

It provides a data-driven comparison of caching architectures in vehicular networks and introduces the 'price-of-fog' metric to evaluate edge caching costs.

Findings

Fog computing greatly reduces core network load.

The cost of fog computing is low and negligible with location-specific content.

Vehicular demand features favor mobile-edge caching benefits.

Abstract

The emergence of in-vehicle entertainment systems and self-driving vehicles, and the latter's need for high-resolution, up-to-date maps, will bring a further increase in the amount of data vehicles consume. Considering how difficult WiFi offloading in vehicular environments is, the bulk of this additional load will be served by cellular networks. Cellular networks, in turn, will resort to caching at the network edge in order to reduce the strain on their core network, an approach also known as mobile edge computing, or fog computing. In this work, we exploit a real-world, large-scale trace coming from the users of the We-Fi app in order to (i) understand how significant the contribution of vehicular users is to the global traffic demand; (ii) compare the performance of different caching architectures; and (iii) studying how such a performance is influenced by recommendation systems and content locality. We express the price of fog computing through a metric called price-of-fog, accounting for the extra caches to deploy compared to a traditional, centralized approach. We find that fog computing allows a very significant reduction of the load on the core network, and the price thereof is low in all cases and becomes negligible if content demand is location specific. We can therefore conclude that vehicular networks make an excellent case for the transition to mobile-edge caching: thanks to the peculiar features of vehicular demand, we can obtain all the benefits of fog computing, including a reduction of the load on the core network, reducing the disadvantages to a minimum.