WiFi and Multiple Interfaces: Adequate for Virtual Reality?
Huanle Zhang, Ahmed Mustafa Elmokashfi, Prasant Mohapatra · 2018
In this paper, we investigate whether IEEE 802.11ac WiFi can support VR applications. To this end we conduct a controlled study of WiFi performance in an indoor setting. Our measurements reveal that WiFi transmissions suffer from high latency and jitter, which makes WiFi systems inadequate for VR applications. For example, the round-trip delay can be as high as 228ms, and more than 24.2% packets experience jitter higher than 1ms. To locate the root cause of the high latency and jitter, we dissect the network stack layer by layer and find that the main culprit is the wireless channel transmission time. To reduce the channel transmission time, we propose using multiple network interfaces running on non-overlapping channels. By using only two interfaces, we (1) reduce the median round-trip delay by 28.6% and jitters of higher than 1ms by 11.5% compared to the best single interface in UDP transmissions, and (2) reduce the median round-trip delay by 38.9% in TCP transmissions. We believe that this paper sheds some light on whether we can make today's WiFi systems VR-ready by using multiple interfaces.