Air-Ground Integrated Vehicular Network Slicing With Content Pushing and Caching

TLDR

The paper proposes an Air‑Ground Integrated Vehicular Network that uses high‑altitude platforms to proactively push content to vehicles and roadside units to provide on‑demand unicast, and introduces a service‑oriented network slicing approach to allocate heterogeneous resources to application slices with guaranteed QoS. The authors analytically model resource provisioning in AGIVEN slicing, deriving optimal HAP broadcast‑rate and vehicle‑cache trade‑offs for map services, on‑board hit ratios for popular content, and minimal RSU transmission rates to satisfy slice delay constraints. Analytical results and simulations show that optimal resource provisioning in AGIVEN slicing can reduce RSU transmission rates by 40% while preserving QoS, illustrating the trade‑offs among broadcast rate, cache size, and transmission rate.

Abstract

In this paper, an Air-Ground Integrated VEhicular Network (AGIVEN) architecture is proposed, where the aerial high-altitude platforms (HAPs) proactively push contents to vehicles through large-area broadcast, while the ground roadside units (RSUs) provide high-rate unicast services on demand. To efficiently manage the multi-dimensional heterogeneous resources, a service-oriented network slicing approach is introduced, where the AGIVEN is virtually divided into multiple slices and each slice supports a specific application with guaranteed quality of service (QoS). Specifically, the fundamental problem of multi-resource provisioning in AGIVEN slicing is investigated by taking into account the typical vehicular applications of location-based map and popularity-based content services. For the location-based map service, the capability of HAP-vehicle proactive pushing is derived with respect to the HAP broadcast rate and vehicle cache size, wherein a saddle point exists, indicating the optimal communication-cache resource trading. For the popular contents of common interests, the average on-board content hit ratio is obtained with HAPs pushing newly generated contents to keep on-board cache fresh. Then, the minimal RSU transmission rate is derived to meet the average delay requirements of each slice. The obtained analytical results reveal the service-dependent resource provisioning and trading relationships among RSU transmission rate, HAP broadcast rate, and vehicle cache size, which provides guidelines for multi-resource network slicing in practice. Simulation results demonstrate that the proposed AGIVEN network slicing approach matches the multi-resources across slices, whereby the RSU transmission rate can be saved by 40% while maintaining the same QoS.