Experimental Evaluation of Interactive Edge/Cloud Virtual Reality Gaming over Wi-Fi using Unity Render Streaming

TL;DR

This work evaluates the viability of interactive VR gaming over Wi‑Fi 6 using Unity Render Streaming with an edge server. It characterizes WebRTC-based VR traffic, revealing a distinct pattern where video frames are packetized and delivered in regular 5.56 ms batches, and demonstrates QoS performance at 60 and 90 fps with sub-5 ms RTT and low jitter. The study shows that while batching improves network efficiency, it increases airtime and can delay complete frame assembly, highlighting a trade-off between latency and spectrum usage. The findings offer practical guidance for optimizing Unity Render Streaming parameters and motivate modeling efforts for VR traffic under edge/cloud Wi‑Fi conditions. The results have direct implications for deploying low-latency VR experiences in real-world Wi‑Fi 6 environments and for future work on adaptive bitrate and multi-user scenarios.

Abstract

Virtual Reality (VR) streaming enables end-users to seamlessly immerse themselves in interactive virtual environments using even low-end devices. However, the quality of the VR experience heavily relies on Wireless Fidelity (Wi-Fi) performance, since it serves as the last hop in the network chain. Our study delves into the intricate interplay between Wi-Fi and VR traffic, drawing upon empirical data and leveraging a Wi-Fi simulator. In this work, we further evaluate Wi-Fi's suitability for VR streaming in terms of the Quality of Service (QoS) it provides. In particular, we employ Unity Render Streaming to remotely stream real-time VR gaming content over Wi-Fi 6 using Web Real-Time Communication (WebRTC), considering a server physically located at the network's edge, near the end user. Our findings demonstrate the system's sustained network performance, showcasing minimal round-trip time (RTT) and jitter at 60 and 90 frames per second (fps). In addition, we uncover the characteristics and patterns of the generated traffic streams, unveiling a distinctive video transmission approach inherent to WebRTC-based services: the systematic packetization of video frames (VFs) and their transmission in discrete batches at regular intervals, regardless of the targeted frame rate. This interval-based transmission strategy maintains consistent video packet delays across video frame rates but leads to increased Wi-Fi airtime consumption. Our results demonstrate that shortening the interval between batches is advantageous, as it enhances Wi-Fi efficiency and reduces delays in delivering complete frames.

Figures (26)

• Figure 1: Remote streaming process. Adapted from shi2015survey.
• Figure 2: SU EDCA: CSMA/CA Process.
• Figure 3: A snapshot of the experimental setup.
• Figure 4: Testbed components.
• Figure 5: Screenshots of the VR games.